{"paper_id":"3f46902a-a624-41ec-b22d-11fd67b77075","body_text":"Development of a determination method for six silymarin in powdered milk thistle extract | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Development of a determination method for six silymarin in powdered milk thistle extract Tao Lan, wenyu zhang, qi zhou, jinli huang, congcong yu, shihui luo, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3828831/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study aims to develop a user-friendly and efficient high-performance liquid chromatography method for the detection of six silymarin in powdered milk thistle extract. On the basis of existing standard methods, a simpler prepared mobile phase was used, and the gradient program of mobile phase was optimized. The effectiveness of this method was verified through methodological investigations such as instrument precision experiments, stability experiments, repeatability experiments, and spiked recovery experiments. The method was applied to the detection of 42 batches of actual samples of powdered milk thistle extract. Under optimized mobile phase and gradient elution conditions, six silymarin compounds in powdered milk thistle extract could be effectively separated from the matrix with baseline resolution. There was a good linear relationship between the concentration of the six silymarin compounds in the range of 5~150 μg/mL, with a limit of detection (LOD) of 25 mg/kg. The precision, stability, and repeatability of the method were all below 5%, and the recovery rates at three spiked levels range from 92% to 108%, with RSDs below 4%, indicating its excellent precision and stability. This method was user-friendly and efficient, with good accuracy, making it suitable for the analysis and detection of real samples. During the actual sample testing, significant variations were observed in the content of the six silymarin compounds among different products. The establishment of this method can be utilized for quality control of powdered milk thistle extract products. powdered milk thistle extract silymarin high performance liquid chromatography (HPLC) quality control Figures Figure 1 1. Introduction Milk thistle extract is a powdered extract product produced through processes such as pressing to remove oil, extracting with ethanol or ethyl acetate, concentration, degreasing, drying, crushing, and blending, using the dried fruit shell of the plant Silybum marianum (L.) Gaertner [ 1 ] belonging to the Compositae family as raw material [ 2 ] . It has been reported in literature that milk thistle extract has protective effects on the liver, antioxidant activity, and hypolipidemic effects [ 3 ] , and has been widely used in medicine [ 3 , 4 ] , health food [ 5 , 6 ] , cosmetics [ 7 , 8 ] , and other fields. Silymarin, the main active ingredient in milk thistle extract, mainly includes six flavonolignans substances, including silybin A, silybin B, isosilybin A, isosilybin B, silydianin, and silicristin. It is reported that the content of silybin is richer than that of iso-silybin in seed extract [ 9 ] , so the Chinese Pharmacopoeia (2010 version) [ 10 ] takes silybin A and silybin B as the quality indicators of milk thistle extract. The European Pharmacopoeia [ 11 ] , the United States Pharmacopoeia [ 12 ] , and some association standard [ 13 ] took all six types of silymarin as the main quality indicators of milk thistle extract, and specify their standard value ranges. Therefore, establishing a standard method for detecting the six types of silymarin in milk thistle extract is extremely important for quality control of milk thistle extract. The six types of silymarin are all isomers [ 14 ] , and there are also spatial stereoisomers among them, which makes the separation, purification, and analysis of these com-pounds difficult [ 15 ] . At the same time, due to the existence of other impurities in milk thistle extracts, there is a certain matrix effect, which poses a great challenge to the detection of the six types of silymarin in milk thistle extracts. Currently, the most commonly reported detection methods are HPLC [ 16 – 18 ] , GC-MS [ 19 – 21 ] , LC-MS/MS [ 22 – 24 ] , capillary electrophoresis (CE) [ 25 , 26 ] , etc. Among which HPLC was widely used due to its good universality and high resolution. As the content of silymarin in milk thistle extract is about 30–65%, and the content of each type of silymarin is greater than 1%, HPLC is more suitable for establishing the corresponding detection method. European Pharmacopoeia and United States Pharmacopoeia and other standard methods are also based on gradient elution HPLC, with differences being minor. They usually use mobile phase A: phosphoric acid-methanol-water (0.5:35:65, v/v/v); mobile phase B: phosphoric acid-methanol-water (0.5:50:50, v/v/v) for gradient elution. This method can basically achieve baseline separation between milk thistle extract matrix and multiple types of silymarin. However, it is difficult to achieve baseline separation for milk thistle extract matrix containing more impurities. Additionally, these mobile phase preparation processes are relatively cumbersome and complex. In order to improve the universality and ease of use of the method, this study aims to develop a detection method for six types of silymarin in complex matrices of milk thistle extracts with a simpler mobile phase system based on previous standard methods. Through methodological validation, we will establish a methodological foundation for establishing corresponding detection method standards, which can be used for quality control of milk thistle extract products. 2. Materials and Methods 2.1 Materials Silymarins standards: silybin A (C25H22010); CAS: 22888-70-6, purity ≥ 98%, silybin B (C25H22010); CAS: 142797-34-0, purity ≥ 98%, isosilybin A (C25H22010); CAS: 142796-21-2, purity ≥ 98%, isosilybin B (C25H22010); CAS: 142796-22-3, purity ≥ 98%, silychristin (C25H22010); CAS: 33889-69-9, purity ≥ 98%, silydianin (C25H22010); CAS: 29782-68-1, purity ≥ 98%, were bought from Shanghai Yuanye Biotechnology Co., Ltd. Chromatographic methanol (CH4O) was from Merck, Germany. Chromatographic acetic acid (CH3COOH) was from China National Pharmaceutical Group Chemical Reagent Co., Ltd. Aqueous filter nylon membrane (13 mm, 0.45 μm) was bought from Jinteng Experimental Equipment Co., Ltd. 2.2 Instruments iChrom5100 analytical domestic liquid chromatograph equipped with DAD detector was from Dalian Yilite Analytical Instruments Co., Ltd. Zorbax SB-C18 chromatographic column (4.6mm × 250mm, 5 μm. 100 Å) was from Agilent Technology (China) Co., Ltd. Thmorgan VM200 vortex oscillator was bought from Tormorgan Biotechnology Co., Ltd. HITACHI CF15RXII centrifuge was bought from Hitachi Corporation. Sartorius analytical balance was from Sartorius Scientific Instruments (Beijing) Co., Ltd. ELGA Pure Water Instrument was from Beijing Chengyi Hengyi Technology Co., Ltd. LMDTC-15F ultrasonic cleaning instrument was from Beijing Green Cotton Technology Co., Ltd. MPE series high-throughput vacuum parallel concentrator was from Ruike Group Co., Ltd. 2.3 Solution preparation 2.3.1 Mobile phase Mobile phase A was an aqueous solution containing 1% acetic acid, and the water was self-made by a laboratory pure water analyzer with a conductivity of 18.2 MΩ. It was filtered through an aqueous phase filter membrane and degassed by ultrasound before use. Mobile phase B was methanol containing 1% acetic acid, which was filtered through an organic phase filter membrane and degassed by ultrasound before use. 2.3.2 Standard mixed stock solution Accurately weighed 10 mg of the six silymarins standards and placed them in a 10 mL volumetric flask. Dissolved them in methanol and brought the volume up to 10 mL, preparing them to a concentration of 1000 μg/mL of standard mixed stock solution. This solution was stored in a refrigerator at 4 ℃, keeping away from light for future use. The expiration date for this solution was one month. 2.3.3 Standard working solution Diluted the mixed standard stock solution of six silymarins with methanol as solvent to prepare a series of standard working solutions with concentrations of 150, 125, 100, 75, 50, 10, and 5 μg/mL. This solution should be prepared fresh for each use. 2.4 Sample pretreatment Accurately weigh 0.2 g of the test sample (accurate to 0.1 mg) and place it in a 50 mL centrifuge tube. Add 20 mL of methanol, vortex for 5 minutes, ultrasonic extraction for 30 minutes, centrifuge at 10000 rpm for 15 minutes, and take the upper layer of the solution. Filter through a 0.45 μm organic phase filter membrane and dilute 20 times. Transfer 1 mL to a liquid chromatography injection vial and wait for injection. 2.5 Liquid chromatography conditions a) Chromatographic column: Zorbax SB~C18 chromatographic column (4.6 × 250 mm, 5.0 μm) ; b) Detection wavelength: 288 nm; c) Mobile phase: Mobile phase A: 1% acetic acid water; Mobile phase B: 1% acetic acid methanol, elution gradient as shown in Table 1. Table 1 Mobile Phase Gradient Program Time(min) Mobile phase A (%) Mobile phase B (%) 0 95 5 20 80 20 25 50 50 40 50 50 40.1 95 5 50 95 5 d) Flow rate: 1.0 mL/min; e) Injection volume: 10 μL; f) Column temperature: 30 ℃. 2.6 Standard curve Inject a series of standard working solutions prepared according to the \"2.5\" liquid chromatography conditions into the instrument for analysis. Use the concentration of each silymarins as the horizontal coordinate and the peak area (mAU) response value as the vertical coordinate to plot a series of standard curves, and obtain the linear regression equation of the standard curve for the six silymarins species. 2.7 Instrument precision, stability, and repeatability tests Under the same instrument conditions, take the standard working solution of the six silymarins at a concentration of 100 μg/mL and repeat injection 6 times according to the \"2.5\" chromatographic conditions, and calculate the RSD of their peak areas to determine the instrument precision. Then accurately weigh 1.0 g (accurate to 0.001 g) of actual extract samples, prepare the extract solution using the \"2.4\" pretreatment method, and analyze it under the \"2.5\" chromatographic conditions in a single day. Test it once every 2 hours for a total of 6 measurements, and calculate the RSD of their peak areas to determine the stability of the method. Finally, accurately weigh 6 portions of actual extract samples, with each portion of 1.0 g (accurate to 0.001g), prepare the extract solution using the \"2.4\" pretreatment method, and inject the prepared extract solution into the instrument under the \"2.5\" chromatographic conditions for analysis, and calculate the RSD of their peak areas to determine the repeatability of the method. 2.8 The recovery tests Due to the high price of the six standards of silymarin and the large amount of standard addition required for the recovery test of the six silymarin species that exist constantly, according to the \"Regulations on the Management of Supplementary Food Inspection Methods\" [27] , \"When necessary, a real positive sample with guaranteed uniformity and stability, a simulated added sample, or a quality control sample shall be used for inter-laboratory verification.\" An actual sample collected was used as a spiked sample and 20%, 40%, and 60% of the actual sample were spiked for the recovery test. Three parallel actual samples were used. Accurately weighed 0.2 g (accurate to 1mg) of milk thistle extract samples each for 12 times, numbered from 1 to 12, of which 1-3 were used as the background (matrix samples), 4-6 were the test solution with a spiked amount of 20% (0.04g) of the sample from area No.17, 7-9 were the test solution with a spiked amount of 40% (0.08g) of the sample from area No.17, and 10-12 were the test solution with a spiked amount of 60% (0.12g) of the sample from area No.17. The test solution and the low, medium, and high concentration spiked samples were analyzed by HPLC. And the recovery rate and relative standard deviation at the three added levels were calculated to investigate the accuracy of the method. 2.9 Data processing The linear regression equation and correlation coefficient of the standard curve in this paper were obtained using the Elite iChrom 5100 workstation. Other data were processed using Origin 8.5 and Excel 2010, and the graphs were plotted. The experimental data were the average of three parallel experiments. 3. Results & Discussion 3.1. Optimization of liquid chromatography conditions In order to achieve effective separation of the six types of silymarin and matrix components in milk thistle extract samples, this study refers to the method for the determination of silymarin in Chinese Pharmacopoeia [ 10 ] . The Pharmacopoeia method uses a C 18 chromatographic column and methanol-water-glacial acetic acid (48:52:1) as the mobile phase. In this paper, the same liquid phase conditions (mobile phase condition 1) were used, and the results are shown in Fig. 1 a. As shown in the figure, except for silychristin and silydianin, which cannot be separated from adjacent matrix components, the separation of silibinin A, silibinin B, isosilibinin A, and isosilibinin B is good. In order to achieve good separation between the analytes and the matrix with minimum changes to the standard method, it is proposed to lower the proportion of mobile phase B within 0–20 minutes to regulate the separation between silychristin and silydianin, and the adjacent matrix. A gradient program (mobile phase condition 2) was used with the following conditions: 0–20 minutes, 20%-48% B; 20–40 minutes, 48% B; 40-40.1 minutes, 48%-20%; and 40.1–50.1 minutes, 20% B. The result shown in Fig. 1 b indicates that silychristin was effectively separated from the matrix, but silydianin was still not separated from the matrix, while the other four silymarin s were well separated. The proportion of mobile phase B within 0–20 minutes was reduced in order to achieve a good separation between silymarin and the matrix. A gradient program (mobile phase condition 3) was used with the following conditions: 0–20 minutes, 5%-20% B; 20–25 minutes, 20%-50% B; 25–40 minutes, 50% B; 40-40.1 minutes, 50%-5% B; and 40.1–50.1 minutes, 5% B. As shown in Fig. 1 c, the matrix had little effect on the analysis of the analytes (silychristin and silydianin), and each analyte achieved baseline separation. This indicates that changing the elution program can achieve the separation of impurity peaks from the chromatographic peaks of the analytes, reducing the possibility of impurity peak interference and thereby eliminating the need for purification treatment of the extract, making the operation convenient and time-saving. The analysis time was similar to that of the methods in the United States Pharmacopoeia and European Pharmacopoeia, so subsequent experiments and methodological validation were conducted using this gradient program. Using this gradient program, standard samples of the six analytes were detected, and the chromatogram shown in Fig. 1 d indicates that all six standard samples were well separated. In summary, the final liquid chromatography conditions for this experiment are: mobile phase A: 1% acetic acid water, mobile phase B: 1% acetic acid methanol, elution mode: 0 ~ 20 min,5%~20%B; 20 ~ 25 min, 20%~50%B; 25 ~ 40 min, 50%B; 40 ~ 40.1 min, 50%~5%B; 40.1 ~ 50.1 min, 5%B. The flow rate is 1 mL/min. 3.2 Linear range and LOD Based on the concentrations and response values of six types of silymarin at seven con-centration points, standard curves were plotted for each type of silymarin. The results showed that within the concentration range of 5 ~ 150 µg/mL, the response intensity values of the six types of silymarin had good linear relationships with their concentrations, and the linear correlation coefficients (R 2 ) of the six types of silymarin were ≥ 0.999. The extract samples spiked with the six types of silymarin standards were gradually diluted for testing and analysis, and their peak height to baseline noise height ratios were calculated. The detection limit (LOD) of the method was determined when the signal-to-noise ratio (S/N) was 3 (S is the peak height of the reference standard, N is the baseline noise height). The LODs of the six types of silymarin were 25 mg/kg, and the results are shown in Table 2 . Table 2 Linear range and LOD of six silymarins silymarins linear equation Linear range (µg/mL) correlation coefficients (R 2 ) LOD (mg/kg) Silychristin Y = 31.5*X-41.6 5 ~ 150 0.9996 25 Silydianin Y = 24.6*X-22.3 5 ~ 150 0.9995 25 Silybin A Y = 29.1*X-18.3 5 ~ 150 0.9998 25 Silybin B Y = 28.4*X-20.9 5 ~ 150 0.9997 25 Isosilybin A Y = 33.3*X-27.4 5 ~ 150 0.9993 25 Isosilybin B Y = 34.7*X + 3.6 5 ~ 150 0.9995 25 3.3 Instrument precision, method stability, and repeatability This study evaluated the instrument accuracy, method stability and repeatability, and the precision results of the instrument within the day were summarized in Table 3 . The daily accuracy of this instrument for 6 silymarins was less than 2%, indicating that this method had good accuracy and stability within one day. The stability and repeatability of the method were evaluated using actual samples, and the peak areas of the liquid chromatography peaks of each substance were used as reference indicators. The results were summarized in Tables 4 and 5 . As shown in the table, the daily stability RSD of each substance was less than 3.2%, and the repeatability RSD was less than 3%. These parameters were within the acceptable range of the US Food and Drug Administration's guidelines for the development of analytical methods and the single laboratory validation guidelines for AOAC dietary supplements and phytochemical methods [ 28 , 29 ] . Compared with other methods [ 24 ] , this method has better accuracy and can be used for the detection of six silymarins in actual samples of silymarin extract. Table 3 Instrument precision test results of six silymarins (n = 6) silymarins peak areas RSD(%) 1 2 3 4 5 6 Silychristin 4944.6 4956.5 4955.5 4964.9 4984.9 4990.2 0.4 Silydianin 3740.9 3743.6 3740.6 3846.9 3759.0 3761.0 1.1 Silybin A 2148.9 2136.5 2146.5 2201.0 2158.8 2161.1 1.0 Silybin B 6670.7 6667.5 6655.5 6665.0 6623.4 6628.9 0.3 Isosilybin A 5059.4 5035.1 5039.1 5066.8 5047.4 5043.6 0.2 Isosilybin B 5440.7 5452.1 5451.1 5605.3 5482.2 5481.9 1.1 Table 4 Stability test results of six silymarins (n = 6) silymarins peak areas RSD(%) 1 2 3 4 5 6 Silychristin 1415.3 1420.6 1415.0 1438.8 1445.8 1447.6 1.0 Silydianin 413.7 422.3 418.3 407.8 410.4 415.7 1.3 Silybin A 1467.9 1420.8 1416.9 1506.8 1512.9 1523.1 3.2 Silybin B 2013.4 2023.6 2022.4 2112.5 2123.2 2129.5 2.7 Isosilybin A 499.2 502.8 503.8 503.7 507.0 509.5 0.7 Isosilybin B 306.0 301.8 323.5 319.6 320.6 324.6 3.1 Table 5 Repeatability test results of six silymarins (n = 6) silymarins peak areas RSD(%) 1 2 3 4 5 6 Silychristin 1549.7 1514.9 1518.0 1521.1 1560.6 1532.6 1.2 Silydianin 506.7 479.3 477.9 481.9 497.3 489.5 2.3 Silybin A 1515.0 1579.0 1583.8 1597.1 1645.8 1615.6 2.8 Silybin B 2238.1 2247.4 2276.0 2275.3 2242.9 2295.8 1.0 Isosilybin A 612.5 636.7 644.8 643.6 664.4 649.8 2.7 Isosilybin B 338.4 341.4 342.3 342.2 351.3 356.8 2.1 3.4 Recovery rate As the content of these six types of silymarins in milk thistle extracts is generally above 1%, this study used constant spiked levels (20%, 40%, and 60% of the sample amount) to spike actual samples. After three parallel experiments, the results of the recovery experiments for the samples were shown in Table 6 . As can be seen from the table, each type of silymarins maintained good recovery rates at the three spiked levels, ranging between 92% and 108%, with RSDs less than 4%, which meets the quality control requirements for food physical and chemical testing in GB/T 27404 [ 30 ] . The method has good recoveries. This result indicates that the established detection method in this study has high recoveries and good precision under different spiked levels, and can meet the requirements for detecting six types of silymarins in actual samples. Table 6 Recovery results of six silymarins in actual samples (n = 3) silymarins Spiked level (20% sample) Spiked level (40% sample) Spiked level (60% sample) Recovery rate (%) RSD r (%) Recovery rate (%) RSD r (%) Recovery rate (%) RSD r (%) Silychristin 92.9 2.3 96.0 1.8 103.1 1.0 Silydianin 97.3 1.9 108.4 3.4 100.7 3.4 Silybin A 99.8 0.7 100.0 0.9 93.7 1.0 Silybin B 93.2 1.2 92.8 0.8 93.7 0.8 Isosilybin A 95.7 3.4 93.2 3.2 101.2 1.3 Isosilybin B 92.0 2.2 92.4 3.1 93.9 3.9 3.5 Actual sample determination The content of 6 silymarins in 42 milk thistle extract samples was analyzed and measured based on the method described in the paper, and the results were summarized in Table 7 . As shown in the table, there were significant differences in the content of the six silymarins corresponding to different products, which were related to the raw materials and production processes used in each product. Therefore, this also laid a solid foundation for formulating quality standards for silymarin extracts. Table 7 Contents of six silymarins in actual samples (n = 3) # Silybin A (%) Silybin B (%) Isosilybin A (%) Isosilybin B (%) Silychristin (%) Silydianin (%) 1 12.0 18.7 3.2 1.2 9.1 1.0 2 11.9 17.6 2.9 1.2 8.3 0.8 3 11.5 17.2 3.0 0.9 8.2 1.1 4 12.1 19.2 3.3 1.4 8.2 1.1 5 11.2 17.4 3.5 1.4 10.2 1.8 6 12.2 20.7 4.4 1.2 13.2 0.8 7 12.2 19.0 3.3 1.5 9.2 1.8 8 18.3 27.7 5.8 2.2 15.4 3.6 9 11.3 18.3 4.4 1.4 10.6 6.7 10 11.3 17.5 3.4 1.0 9.9 1.7 11 9.3 14.6 2.8 0.9 8.7 2.2 12 8.7 13.6 2.9 1.2 9.0 1.1 13 9.7 15.3 3.1 1.0 9.1 1.3 14 8.1 12.4 2.9 1.2 8.6 1.2 15 10.5 15.8 3.1 1.3 9.1 1.3 16 8.8 13.3 3.2 2.2 8.5 2.6 17 10.2 15.8 2.9 1.0 8.8 1.7 18 10.1 15.5 3.0 1.1 9.1 2.5 19 11.9 18.5 3.4 1.1 9.0 2.4 20 9.7 15.5 3.3 1.4 9.1 1.4 21 10.5 16.0 2.8 1.0 8.7 1.0 22 11.3 17.7 3.1 1.0 8.8 1.1 23 9.5 14.7 3.0 1.0 8.2 1.3 24 11.4 17.0 3.3 1.4 9.0 2.1 25 11.7 18.4 3.2 1.0 8.8 0.9 26 14.1 21.5 3.3 1.0 9.3 0.8 27 13.0 21.7 4.5 1.3 13.4 1.5 28 12.6 21.1 4.3 1.2 13.0 1.5 29 13.1 21.5 4.5 1.3 12.8 1.6 30 14.0 21.1 3.2 1.4 9.9 1.0 31 14.3 21.9 4.1 1.6 11.2 2.9 32 10.5 16.3 2.7 1.2 9.3 1.7 33 9.6 15.1 2.7 1.1 9.3 1.8 34 13.4 21.2 4.3 1.7 11.8 1.9 35 9.0 13.8 2.7 0.8 8.6 1.5 36 12.7 19.9 3.7 1.2 11.0 2.0 37 9.0 13.9 2.7 1.1 7.9 1.3 38 8.2 8.4 2.6 0.8 8.3 1.6 39 12.9 19.9 3.7 1.1 11.1 1.0 40 12.0 18.7 2.7 1.0 8.0 1.0 41 11.1 17.7 3.4 1.1 9.0 1.7 42 2.3 7.1 3.8 1.9 10.7 1.2 Range 2.3 ~ 18.3 7.1 ~ 21.7 2.7 ~ 5.8 0.8 ~ 2.2 7.9 ~ 15.4 0.8 ~ 6.7 4. Conclusions This paper established a HPLC method for the detection of six silymarins in milk thistle extracts by optimizing the mobile phase composition and gradient conditions based on several standard methods. Under the optimal analytical conditions, the six silymarins compounds in the milk thistle extract can achieve good baseline separation from the matrix with good resolution. At the same time, the limit of detection of this method was 25 mg/kg, and the RSDs of repeatability and stability were < 3.2%. The recovery rates at three spiking levels ranged from 92–108%, and the RSDs were < 4%. This method had good sensitivity, repeatability, and accuracy and can be used for the analysis of actual samples. Through testing 42 batches of milk thistle extract samples, it was found that there were significant differences in the content of the six silymarins corresponding to different products. The establishment of this method provided a foundation for testing methods and data that can be used to develop quality standards for milk thistle extracts, and it plays an important role in promoting the high-quality development of plant extract industry. Declarations Declaration of interest The authors declare that there is no conflict of interest. The authors alone are responsible for the accuracy and integrity of the paper content. Ethical approval This article did not involve animal experiments, so there was no need for ethical examination. Author Contribution Conceptualization, project administration, data curation, supervision, T.L.; methodology, writing original draft preparation, data curation, Z.W.Y.; methodology, data curation, Z.Q.; investigation, data curation, H.J.L.; data curation, Y.C.C.; writing-review and editing, L.S.H.; writing-review and editing, Z.X.; supervision, H.R.Q. All authors have read and agreed to the published version of the manuscript. References Pickoval D, Ostry V, Toman J, Malir F (2020) Toxins (Basel) 12(12): 782. Association Standards Committee of China Industry-University-Research Institute Collaboration Association (2023) Quality Requirements of Milk Thistle Extract (T/CAB 0277-2023). Beijing: Standards Press of China. Fanoudi S, Alavi MS, Karimi G, Hosseinzadeh H (2020) Drug Chemi Toxicol 43(3): 240-254. Ross SM, (2008) Holist Nurs Pract 22(5): 299-300. Soleimani V, Delghandi PS, Moallem SA, Karimi G (2019) Phytother Res 33(6): 1627-1638. Abenacoli L, Izzo AA, Milic N, Cicala C, Santini A, Capasso R (2018) Phytother Res 2(11): 2202-2213. Vaid M, Katiy SK (2010) Int J Oncol 36(5): 1053-60. Saurat JH, Reygagne P, Josse G, Hamidou Z, Bianovici S, Ramel F, Durbise E, Lovati C, Bellani E, Bystrzanowska D, Chlebus E, Kowalska-Oledzka E, D’Auzers G, Digabel JL, Filiol J, Lauze C, Ortiz-Brugues A, Nocera T (2022) J Pers Med 13(1): 96. Hoh CSL, Boocock DJ, Marczylo TH, Brown VA, Cai H, Steward WP, Berry DP, Gescher AJ (2007) J Agric Food Chem 55(7): 2532-2535. National Pharmacopoeia Commission. Pharmacopoeia of the People's Republic of China, (2020) 1 Volumes. Beijing: China Medical Science and Technology Press, 84. European Pharmacopoeia 10.6. (2022) Milk Thistle Dry Extract, Refined and Standardised (Silybi mariani extractum siccum raffinatum et normatum). 2071. United States Pharmacopoeia. Powdered Milk Thistle Extract. USP35–NF30, 1387. Association Standards Committee of China Chamber of Commerce of Medicine &Health Products Importers & Exporters (2016) Plant extract-Milk thistle extract (Active Pharmaceutical Ingredient) (T/CCCMHPIE 1.21—2016). Beijing: Standards Press of China. Lee JI, Narayan M, Barrett JS (2007) J Chromatogra B 845(1): 95-103. Quaglia M, Bossu E, Donati E, Mazzanti G, Brandt A (1999) J Pharmaceut Biomed 19(3-4): 435-442. Cheilari A, Sturm S, Intelmann D, Seger C, Stuppner H (2016) J Agric Food Chem 64(7): 1618-1626. Radjabian T, Rezazadeh SH, Huseini HF (2008) Iran J Sci Technol A 32(A2): 141-146. Tayoub G, Sulaiman H, Alorifi M (2018) Int J Herb Med 6(2): 110-114. Mhamdi B, Abbassi F, Smaoui A, Abdelly C, Marzouk B (2016) Pak J Pharm Sci 29(3): 953-959. Padma M, Ganesan S, Jayaseelan T, Azhagumadhavan S, Sasikala P, Senthilkumar S, Mani P (2019) J Drug Deliv The 9(1): 85-89. Tajabadi F, Ghorbanin-Ohooji M, Gholami A, Yekta MG, Ghasemi SV, Nabati F, Sadri SH (2023) Biomed. Chromatogra. 37(3): e5566. Lazzeroni M, Petrangolini G, Iriberri JAL, Avellana JP, Robuste DT, Cagnacci S, Macis D, Aristarco V, Bonanni B, Morazzoni P, Johansson H, Riva A (2020) Molecules 25(12): 2918. Kuki A, Nagy L, Deak G, Nagy M, Zsuga M, Keki S (2012) Chromatographia 75: 175-180. Muchiri RN, Van Breemen RB (2021) J AOAC Int 104(1): 232-238. Riasová P, Jenčo J, Moreno-González D, Heyden YV, Mangelings D, Polášek M, Jáč P (2022) Electrophoresis 43(9-10): 930-938. Lu HY, Guan J, Yan F (2021) Mod Chem Resear 50(01): 240-243. Notice of the State Administration of Market Regulation on Issuing the \"Regulations on the Management of Supplementary Inspection Methods for Food\". (2023-03-07). US FDA Guidance for Industry (2018) Bioanalytical Method Validation. Silver Spring, MD. Appendix K (2013) Guidelines for Dietary Supplements and Botanicals. AOAC Int. Gaithersburg, MD. GB/T 27404 (2008) Criterion on quality control of laboratories-Chemical testing of food., Beijing: Standards Press of China. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-3828831\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":true,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":265518962,\"identity\":\"f8743492-0691-4387-89a4-a61619f5f981\",\"order_by\":0,\"name\":\"Tao Lan\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAwUlEQVRIiWNgGAWjYBACPghlw8DATKwWNgYGxgYGhjTStRwmwWFs7GePP/hRcV7enJ39AcOPGgZ5c4JaePISG3vO3Dbc2cxjwNhzjMFwZwNBh+UYNvC23U4wOMzDwMDbwJBgcICQFv43ho1/284BtbA/YPxLlBaJHMNm3rYDQC0MBszE2SLxxnC2zJlkww2HeQwOyxyTMNxASAs/f47BxzcVdvIG548/fPimxkaeoC0oAKhYghT1o2AUjIJRMApwAQDv4Tn86JpSVgAAAABJRU5ErkJggg==\",\"orcid\":\"\",\"institution\":\"China National Institute of Standardization\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Tao\",\"middleName\":\"\",\"lastName\":\"Lan\",\"suffix\":\"\"},{\"id\":265518963,\"identity\":\"64e16056-130e-48ee-85d4-4db1bdd009aa\",\"order_by\":1,\"name\":\"wenyu zhang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"China National Institute of Standardization\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"wenyu\",\"middleName\":\"\",\"lastName\":\"zhang\",\"suffix\":\"\"},{\"id\":265518964,\"identity\":\"bcb4ca6f-1314-4537-913f-2e5a2e04bd15\",\"order_by\":2,\"name\":\"qi zhou\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"China National Institute of Standardization\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"qi\",\"middleName\":\"\",\"lastName\":\"zhou\",\"suffix\":\"\"},{\"id\":265518965,\"identity\":\"14808168-32b1-4854-bad7-290db603e8d8\",\"order_by\":3,\"name\":\"jinli huang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Byhealth Institute of Nutrition \\u0026 Health\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"jinli\",\"middleName\":\"\",\"lastName\":\"huang\",\"suffix\":\"\"},{\"id\":265518966,\"identity\":\"90e6f9f2-0f7b-4cbb-8755-4d2794713f57\",\"order_by\":4,\"name\":\"congcong yu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"China National Institute of Standardization\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"congcong\",\"middleName\":\"\",\"lastName\":\"yu\",\"suffix\":\"\"},{\"id\":265518967,\"identity\":\"13d333a8-c2e2-448f-8a33-678c7c60c914\",\"order_by\":5,\"name\":\"shihui luo\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Byhealth Institute of Nutrition \\u0026 Health\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"shihui\",\"middleName\":\"\",\"lastName\":\"luo\",\"suffix\":\"\"},{\"id\":265518968,\"identity\":\"1675a0aa-237f-4d51-bb37-683c54421582\",\"order_by\":6,\"name\":\"xi zhao\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Byhealth Institute of Nutrition \\u0026 Health\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"xi\",\"middleName\":\"\",\"lastName\":\"zhao\",\"suffix\":\"\"},{\"id\":265518969,\"identity\":\"27d518ae-47bb-4256-b857-00e47292f39f\",\"order_by\":7,\"name\":\"ruikun he\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Byhealth Institute of Nutrition \\u0026 Health\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"ruikun\",\"middleName\":\"\",\"lastName\":\"he\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2024-01-02 07:29:15\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-3828831/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-3828831/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":49293520,\"identity\":\"a9f249ff-16f2-4451-86fa-a3c77910a1a6\",\"added_by\":\"auto\",\"created_at\":\"2024-01-08 06:24:10\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":55427,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003e(a) Chromatogram of milk thistle extract under mobile phase condition 1; (b) Chromatogram of milk thistle extract under mobile phase condition 2; (c) Chromatogram of milk thistle extract under mobile phase condition 3; (d) Chromatograms of six silymarin standards under mobile phase condition 3.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"1.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-3828831/v1/fc3130c08c612286288d85d3.png\"},{\"id\":49425149,\"identity\":\"2d0f3e3e-4628-4ca2-8d39-8f4fbe405f75\",\"added_by\":\"auto\",\"created_at\":\"2024-01-10 15:22:24\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":431018,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-3828831/v1/d0e8852f-00e2-45e7-b7b8-c94ce7a8fce3.pdf\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"Development of a determination method for six silymarin in powdered milk thistle extract\",\"fulltext\":[{\"header\":\"1. Introduction\",\"content\":\"\\u003cp\\u003eMilk thistle extract is a powdered extract product produced through processes such as pressing to remove oil, extracting with ethanol or ethyl acetate, concentration, degreasing, drying, crushing, and blending, using the dried fruit shell of the plant \\u003cem\\u003eSilybum marianum (L.)\\u003c/em\\u003e Gaertner \\u003csup\\u003e[\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e]\\u003c/sup\\u003e belonging to the Compositae family as raw material \\u003csup\\u003e[\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]\\u003c/sup\\u003e. It has been reported in literature that milk thistle extract has protective effects on the liver, antioxidant activity, and hypolipidemic effects \\u003csup\\u003e[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e]\\u003c/sup\\u003e, and has been widely used in medicine \\u003csup\\u003e[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e]\\u003c/sup\\u003e, health food \\u003csup\\u003e[\\u003cspan citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e]\\u003c/sup\\u003e, cosmetics \\u003csup\\u003e[\\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e]\\u003c/sup\\u003e, and other fields.\\u003c/p\\u003e \\u003cp\\u003eSilymarin, the main active ingredient in milk thistle extract, mainly includes six flavonolignans substances, including silybin A, silybin B, isosilybin A, isosilybin B, silydianin, and silicristin. It is reported that the content of silybin is richer than that of iso-silybin in seed extract \\u003csup\\u003e[\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e]\\u003c/sup\\u003e, so the Chinese Pharmacopoeia (2010 version) \\u003csup\\u003e[\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]\\u003c/sup\\u003e takes silybin A and silybin B as the quality indicators of milk thistle extract. The European Pharmacopoeia \\u003csup\\u003e[\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e]\\u003c/sup\\u003e, the United States Pharmacopoeia \\u003csup\\u003e[\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e]\\u003c/sup\\u003e, and some association standard \\u003csup\\u003e[\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e]\\u003c/sup\\u003e took all six types of silymarin as the main quality indicators of milk thistle extract, and specify their standard value ranges. Therefore, establishing a standard method for detecting the six types of silymarin in milk thistle extract is extremely important for quality control of milk thistle extract.\\u003c/p\\u003e \\u003cp\\u003eThe six types of silymarin are all isomers \\u003csup\\u003e[\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]\\u003c/sup\\u003e, and there are also spatial stereoisomers among them, which makes the separation, purification, and analysis of these com-pounds difficult \\u003csup\\u003e[\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e]\\u003c/sup\\u003e. At the same time, due to the existence of other impurities in milk thistle extracts, there is a certain matrix effect, which poses a great challenge to the detection of the six types of silymarin in milk thistle extracts. Currently, the most commonly reported detection methods are HPLC \\u003csup\\u003e[\\u003cspan additionalcitationids=\\\"CR17\\\" citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e]\\u003c/sup\\u003e, GC-MS \\u003csup\\u003e[\\u003cspan additionalcitationids=\\\"CR20\\\" citationid=\\\"CR19\\\" class=\\\"CitationRef\\\"\\u003e19\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR21\\\" class=\\\"CitationRef\\\"\\u003e21\\u003c/span\\u003e]\\u003c/sup\\u003e, LC-MS/MS \\u003csup\\u003e[\\u003cspan additionalcitationids=\\\"CR23\\\" citationid=\\\"CR22\\\" class=\\\"CitationRef\\\"\\u003e22\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR24\\\" class=\\\"CitationRef\\\"\\u003e24\\u003c/span\\u003e]\\u003c/sup\\u003e, capillary electrophoresis (CE) \\u003csup\\u003e[\\u003cspan citationid=\\\"CR25\\\" class=\\\"CitationRef\\\"\\u003e25\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR26\\\" class=\\\"CitationRef\\\"\\u003e26\\u003c/span\\u003e]\\u003c/sup\\u003e, etc. Among which HPLC was widely used due to its good universality and high resolution. As the content of silymarin in milk thistle extract is about 30\\u0026ndash;65%, and the content of each type of silymarin is greater than 1%, HPLC is more suitable for establishing the corresponding detection method. European Pharmacopoeia and United States Pharmacopoeia and other standard methods are also based on gradient elution HPLC, with differences being minor. They usually use mobile phase A: phosphoric acid-methanol-water (0.5:35:65, v/v/v); mobile phase B: phosphoric acid-methanol-water (0.5:50:50, v/v/v) for gradient elution. This method can basically achieve baseline separation between milk thistle extract matrix and multiple types of silymarin. However, it is difficult to achieve baseline separation for milk thistle extract matrix containing more impurities. Additionally, these mobile phase preparation processes are relatively cumbersome and complex.\\u003c/p\\u003e \\u003cp\\u003eIn order to improve the universality and ease of use of the method, this study aims to develop a detection method for six types of silymarin in complex matrices of milk thistle extracts with a simpler mobile phase system based on previous standard methods. Through methodological validation, we will establish a methodological foundation for establishing corresponding detection method standards, which can be used for quality control of milk thistle extract products.\\u003c/p\\u003e\"},{\"header\":\"2. Materials and Methods\",\"content\":\"\\u003cp\\u003e\\u003cem\\u003e2.1 Materials\\u0026nbsp;\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eSilymarins standards: silybin A (C25H22010); CAS: 22888-70-6, purity \\u0026ge; 98%, silybin B (C25H22010); CAS: 142797-34-0, purity \\u0026ge; 98%, isosilybin A (C25H22010); CAS: 142796-21-2, purity \\u0026ge; 98%, isosilybin B (C25H22010); CAS: 142796-22-3, purity \\u0026ge; 98%, silychristin (C25H22010); CAS: 33889-69-9, purity \\u0026ge; 98%, silydianin (C25H22010); CAS: 29782-68-1, purity \\u0026ge; 98%, were bought from Shanghai Yuanye Biotechnology Co., Ltd. Chromatographic methanol (CH4O) was from Merck, Germany. Chromatographic acetic acid (CH3COOH) was from China National Pharmaceutical Group Chemical Reagent Co., Ltd. Aqueous filter nylon membrane (13 mm, 0.45 \\u0026mu;m) was bought from Jinteng Experimental Equipment Co., Ltd.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.2 Instruments\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eiChrom5100 analytical domestic liquid chromatograph equipped with DAD detector was from Dalian Yilite Analytical Instruments Co., Ltd. Zorbax SB-C18 chromatographic column (4.6mm \\u0026times; 250mm, 5 \\u0026mu;m. 100 \\u0026Aring;) was from Agilent Technology (China) Co., Ltd. Thmorgan VM200 vortex oscillator was bought from Tormorgan Biotechnology Co., Ltd. HITACHI CF15RXII centrifuge was bought from Hitachi Corporation. Sartorius analytical balance was from Sartorius Scientific Instruments (Beijing) Co., Ltd. ELGA Pure Water Instrument was from Beijing Chengyi Hengyi Technology Co., Ltd. LMDTC-15F ultrasonic cleaning instrument was from Beijing Green Cotton Technology Co., Ltd. MPE series high-throughput vacuum parallel concentrator was from Ruike Group Co., Ltd.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.3 Solution preparation\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e2.3.1 Mobile phase\\u003c/p\\u003e\\n\\u003cp\\u003eMobile phase A was an aqueous solution containing 1% acetic acid, and the water was self-made by a laboratory pure water analyzer with a conductivity of 18.2 M\\u0026Omega;. It was filtered through an aqueous phase filter membrane and degassed by ultrasound before use.\\u003c/p\\u003e\\n\\u003cp\\u003eMobile phase B was methanol containing 1% acetic acid, which was filtered through an organic phase filter membrane and degassed by ultrasound before use.\\u003c/p\\u003e\\n\\u003cp\\u003e2.3.2 Standard mixed stock solution\\u003c/p\\u003e\\n\\u003cp\\u003eAccurately weighed 10 mg of the six silymarins standards and placed them in a 10 mL volumetric flask. Dissolved them in methanol and brought the volume up to 10 mL, preparing them to a concentration of 1000 \\u0026mu;g/mL of standard mixed stock solution. This solution was stored in a refrigerator at 4 ℃, keeping away from light for future use. The expiration date for this solution was one month.\\u003c/p\\u003e\\n\\u003cp\\u003e2.3.3 Standard working solution\\u003c/p\\u003e\\n\\u003cp\\u003eDiluted the mixed standard stock solution of six silymarins with methanol as solvent to prepare a series of standard working solutions with concentrations of 150, 125, 100, 75, 50, 10, and 5 \\u0026mu;g/mL. This solution should be prepared fresh for each use.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.4 Sample pretreatment\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eAccurately weigh 0.2 g of the test sample (accurate to 0.1 mg) and place it in a 50 mL centrifuge tube. Add 20 mL of methanol, vortex for 5 minutes, ultrasonic extraction for 30 minutes, centrifuge at 10000 rpm for 15 minutes, and take the upper layer of the solution. Filter through a 0.45 \\u0026mu;m organic phase filter membrane and dilute 20 times. Transfer 1 mL to a liquid chromatography injection vial and wait for injection.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.5 Liquid chromatography conditions\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003ea) Chromatographic column: Zorbax SB~C18 chromatographic column (4.6 \\u0026times; 250 mm, 5.0 \\u0026mu;m) ;\\u003c/p\\u003e\\n\\u003cp\\u003eb) Detection wavelength: 288 nm;\\u003c/p\\u003e\\n\\u003cp\\u003ec) Mobile phase: Mobile phase A: 1% acetic acid water; Mobile phase B: 1% acetic acid methanol, elution gradient as shown in Table 1.\\u003c/p\\u003e\\n\\u003cp\\u003eTable 1 Mobile Phase Gradient Program\\u003c/p\\u003e\\n\\u003cdiv align=\\\"Left\\\"\\u003e\\n \\u003ctable border=\\\"1\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"350\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"22.571428571428573%\\\"\\u003e\\n \\u003cp\\u003eTime(min)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"36.857142857142854%\\\"\\u003e\\n \\u003cp\\u003eMobile phase A (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"40.57142857142857%\\\"\\u003e\\n \\u003cp\\u003eMobile phase B (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"22.571428571428573%\\\"\\u003e\\n \\u003cp\\u003e0\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"36.857142857142854%\\\"\\u003e\\n \\u003cp\\u003e95\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"40.57142857142857%\\\"\\u003e\\n \\u003cp\\u003e5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"22.571428571428573%\\\"\\u003e\\n \\u003cp\\u003e20\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"36.857142857142854%\\\"\\u003e\\n \\u003cp\\u003e80\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"40.57142857142857%\\\"\\u003e\\n \\u003cp\\u003e20\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"22.571428571428573%\\\"\\u003e\\n \\u003cp\\u003e25\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"36.857142857142854%\\\"\\u003e\\n \\u003cp\\u003e50\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"40.57142857142857%\\\"\\u003e\\n \\u003cp\\u003e50\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"22.571428571428573%\\\"\\u003e\\n \\u003cp\\u003e40\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"36.857142857142854%\\\"\\u003e\\n \\u003cp\\u003e50\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"40.57142857142857%\\\"\\u003e\\n \\u003cp\\u003e50\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"22.571428571428573%\\\"\\u003e\\n \\u003cp\\u003e40.1\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"36.857142857142854%\\\"\\u003e\\n \\u003cp\\u003e95\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"40.57142857142857%\\\"\\u003e\\n \\u003cp\\u003e5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"22.571428571428573%\\\"\\u003e\\n \\u003cp\\u003e50\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"36.857142857142854%\\\"\\u003e\\n \\u003cp\\u003e95\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"40.57142857142857%\\\"\\u003e\\n \\u003cp\\u003e5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\\n\\u003c/div\\u003e\\n\\u003cp\\u003ed) Flow rate: 1.0 mL/min;\\u003c/p\\u003e\\n\\u003cp\\u003ee) Injection volume: 10 \\u0026mu;L;\\u003c/p\\u003e\\n\\u003cp\\u003ef) Column temperature: 30 ℃.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.6 Standard curve\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eInject a series of standard working solutions prepared according to the \\u0026quot;2.5\\u0026quot; liquid chromatography conditions into the instrument for analysis. Use the concentration of each silymarins as the horizontal coordinate and the peak area (mAU) response value as the vertical coordinate to plot a series of standard curves, and obtain the linear regression equation of the standard curve for the six silymarins species.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.7 Instrument precision, stability, and repeatability tests\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eUnder the same instrument conditions, take the standard working solution of the six silymarins at a concentration of 100 \\u0026mu;g/mL and repeat injection 6 times according to the \\u0026quot;2.5\\u0026quot; chromatographic conditions, and calculate the RSD of their peak areas to determine the instrument precision.\\u003c/p\\u003e\\n\\u003cp\\u003eThen accurately weigh 1.0 g (accurate to 0.001 g) of actual extract samples, prepare the extract solution using the \\u0026quot;2.4\\u0026quot; pretreatment method, and analyze it under the \\u0026quot;2.5\\u0026quot; chromatographic conditions in a single day. Test it once every 2 hours for a total of 6 measurements, and calculate the RSD of their peak areas to determine the stability of the method.\\u003c/p\\u003e\\n\\u003cp\\u003eFinally, accurately weigh 6 portions of actual extract samples, with each portion of 1.0 g (accurate to 0.001g), prepare the extract solution using the \\u0026quot;2.4\\u0026quot; pretreatment method, and inject the prepared extract solution into the instrument under the \\u0026quot;2.5\\u0026quot; chromatographic conditions for analysis, and calculate the RSD of their peak areas to determine the repeatability of the method.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.8 The recovery tests\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eDue to the high price of the six standards of silymarin and the large amount of standard addition required for the recovery test of the six silymarin species that exist constantly, according to the \\u0026quot;Regulations on the Management of Supplementary Food Inspection Methods\\u0026quot; \\u003csup\\u003e[27]\\u003c/sup\\u003e, \\u0026quot;When necessary, a real positive sample with guaranteed uniformity and stability, a simulated added sample, or a quality control sample shall be used for inter-laboratory verification.\\u0026quot; An actual sample collected was used as a spiked sample and 20%, 40%, and 60% of the actual sample were spiked for the recovery test.\\u003c/p\\u003e\\n\\u003cp\\u003eThree parallel actual samples were used. Accurately weighed 0.2 g (accurate to 1mg) of milk thistle extract samples each for 12 times, numbered from 1 to 12, of which 1-3 were used as the background (matrix samples), 4-6 were the test solution with a spiked amount of 20% (0.04g) of the sample from area No.17, 7-9 were the test solution with a spiked amount of 40% (0.08g) of the sample from area No.17, and 10-12 were the test solution with a spiked amount of 60% (0.12g) of the sample from area No.17. The test solution and the low, medium, and high concentration spiked samples were analyzed by HPLC. And the recovery rate and relative standard deviation at the three added levels were calculated to investigate the accuracy of the method.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cem\\u003e2.9 Data processing\\u003c/em\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe linear regression equation and correlation coefficient of the standard curve in this paper were obtained using the Elite iChrom 5100 workstation. Other data were processed using Origin 8.5 and Excel 2010, and the graphs were plotted. The experimental data were the average of three parallel experiments.\\u003c/p\\u003e\"},{\"header\":\"3. Results \\u0026 Discussion\",\"content\":\"\\u003cdiv id=\\\"Sec16\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.1. Optimization of liquid chromatography conditions\\u003c/h2\\u003e \\u003cp\\u003eIn order to achieve effective separation of the six types of silymarin and matrix components in milk thistle extract samples, this study refers to the method for the determination of silymarin in Chinese Pharmacopoeia \\u003csup\\u003e[\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]\\u003c/sup\\u003e. The Pharmacopoeia method uses a C\\u003csub\\u003e18\\u003c/sub\\u003e chromatographic column and methanol-water-glacial acetic acid (48:52:1) as the mobile phase. In this paper, the same liquid phase conditions (mobile phase condition 1) were used, and the results are shown in Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003ea. As shown in the figure, except for silychristin and silydianin, which cannot be separated from adjacent matrix components, the separation of silibinin A, silibinin B, isosilibinin A, and isosilibinin B is good.\\u003c/p\\u003e \\u003cp\\u003eIn order to achieve good separation between the analytes and the matrix with minimum changes to the standard method, it is proposed to lower the proportion of mobile phase B within 0\\u0026ndash;20 minutes to regulate the separation between silychristin and silydianin, and the adjacent matrix. A gradient program (mobile phase condition 2) was used with the following conditions: 0\\u0026ndash;20 minutes, 20%-48% B; 20\\u0026ndash;40 minutes, 48% B; 40-40.1 minutes, 48%-20%; and 40.1\\u0026ndash;50.1 minutes, 20% B. The result shown in Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003eb indicates that silychristin was effectively separated from the matrix, but silydianin was still not separated from the matrix, while the other four silymarin s were well separated.\\u003c/p\\u003e \\u003cp\\u003eThe proportion of mobile phase B within 0\\u0026ndash;20 minutes was reduced in order to achieve a good separation between silymarin and the matrix. A gradient program (mobile phase condition 3) was used with the following conditions: 0\\u0026ndash;20 minutes, 5%-20% B; 20\\u0026ndash;25 minutes, 20%-50% B; 25\\u0026ndash;40 minutes, 50% B; 40-40.1 minutes, 50%-5% B; and 40.1\\u0026ndash;50.1 minutes, 5% B.\\u003c/p\\u003e \\u003cp\\u003eAs shown in Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003ec, the matrix had little effect on the analysis of the analytes (silychristin and silydianin), and each analyte achieved baseline separation. This indicates that changing the elution program can achieve the separation of impurity peaks from the chromatographic peaks of the analytes, reducing the possibility of impurity peak interference and thereby eliminating the need for purification treatment of the extract, making the operation convenient and time-saving. The analysis time was similar to that of the methods in the United States Pharmacopoeia and European Pharmacopoeia, so subsequent experiments and methodological validation were conducted using this gradient program. Using this gradient program, standard samples of the six analytes were detected, and the chromatogram shown in Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003ed indicates that all six standard samples were well separated.\\u003c/p\\u003e \\u003cp\\u003eIn summary, the final liquid chromatography conditions for this experiment are: mobile phase A: 1% acetic acid water, mobile phase B: 1% acetic acid methanol, elution mode: 0\\u0026thinsp;~\\u0026thinsp;20 min,5%~20%B; 20\\u0026thinsp;~\\u0026thinsp;25 min, 20%~50%B; 25\\u0026thinsp;~\\u0026thinsp;40 min, 50%B; 40\\u0026thinsp;~\\u0026thinsp;40.1 min, 50%~5%B; 40.1\\u0026thinsp;~\\u0026thinsp;50.1 min, 5%B. The flow rate is 1 mL/min.\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec17\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.2 Linear range and LOD\\u003c/h2\\u003e \\u003cp\\u003eBased on the concentrations and response values of six types of silymarin at seven con-centration points, standard curves were plotted for each type of silymarin. The results showed that within the concentration range of 5\\u0026thinsp;~\\u0026thinsp;150 \\u0026micro;g/mL, the response intensity values of the six types of silymarin had good linear relationships with their concentrations, and the linear correlation coefficients (R\\u003csup\\u003e2\\u003c/sup\\u003e) of the six types of silymarin were \\u0026ge;\\u0026thinsp;0.999. The extract samples spiked with the six types of silymarin standards were gradually diluted for testing and analysis, and their peak height to baseline noise height ratios were calculated. The detection limit (LOD) of the method was determined when the signal-to-noise ratio (S/N) was 3 (S is the peak height of the reference standard, N is the baseline noise height). The LODs of the six types of silymarin were 25 mg/kg, and the results are shown in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab2\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab2\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 2\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eLinear range and LOD of six silymarins\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"5\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003esilymarins\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003elinear equation\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eLinear range (\\u0026micro;g/mL)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003ecorrelation coefficients (R\\u003csup\\u003e2\\u003c/sup\\u003e)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eLOD (mg/kg)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilychristin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eY\\u0026thinsp;=\\u0026thinsp;31.5*X-41.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5\\u0026thinsp;~\\u0026thinsp;150\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.9996\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e25\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilydianin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eY\\u0026thinsp;=\\u0026thinsp;24.6*X-22.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5\\u0026thinsp;~\\u0026thinsp;150\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.9995\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e25\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eY\\u0026thinsp;=\\u0026thinsp;29.1*X-18.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5\\u0026thinsp;~\\u0026thinsp;150\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.9998\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e25\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eY\\u0026thinsp;=\\u0026thinsp;28.4*X-20.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5\\u0026thinsp;~\\u0026thinsp;150\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.9997\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e25\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eY\\u0026thinsp;=\\u0026thinsp;33.3*X-27.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5\\u0026thinsp;~\\u0026thinsp;150\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.9993\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e25\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eY\\u0026thinsp;=\\u0026thinsp;34.7*X\\u0026thinsp;+\\u0026thinsp;3.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5\\u0026thinsp;~\\u0026thinsp;150\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.9995\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e25\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec18\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.3 Instrument precision, method stability, and repeatability\\u003c/h2\\u003e \\u003cp\\u003eThis study evaluated the instrument accuracy, method stability and repeatability, and the precision results of the instrument within the day were summarized in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab3\\\" class=\\\"InternalRef\\\"\\u003e3\\u003c/span\\u003e. The daily accuracy of this instrument for 6 silymarins was less than 2%, indicating that this method had good accuracy and stability within one day. The stability and repeatability of the method were evaluated using actual samples, and the peak areas of the liquid chromatography peaks of each substance were used as reference indicators. The results were summarized in Tables\\u0026nbsp;\\u003cspan refid=\\\"Tab4\\\" class=\\\"InternalRef\\\"\\u003e4\\u003c/span\\u003e and \\u003cspan refid=\\\"Tab5\\\" class=\\\"InternalRef\\\"\\u003e5\\u003c/span\\u003e. As shown in the table, the daily stability RSD of each substance was less than 3.2%, and the repeatability RSD was less than 3%. These parameters were within the acceptable range of the US Food and Drug Administration's guidelines for the development of analytical methods and the single laboratory validation guidelines for AOAC dietary supplements and phytochemical methods \\u003csup\\u003e[\\u003cspan citationid=\\\"CR28\\\" class=\\\"CitationRef\\\"\\u003e28\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR29\\\" class=\\\"CitationRef\\\"\\u003e29\\u003c/span\\u003e]\\u003c/sup\\u003e. Compared with other methods \\u003csup\\u003e[\\u003cspan citationid=\\\"CR24\\\" class=\\\"CitationRef\\\"\\u003e24\\u003c/span\\u003e]\\u003c/sup\\u003e, this method has better accuracy and can be used for the detection of six silymarins in actual samples of silymarin extract.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab3\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 3\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eInstrument precision test results of six silymarins (n\\u0026thinsp;=\\u0026thinsp;6)\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"8\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003esilymarins\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"6\\\" nameend=\\\"c7\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003epeak areas\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003eRSD(%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e5\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e6\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilychristin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e4944.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e4956.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e4955.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e4964.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e4984.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e4990.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilydianin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e3740.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e3743.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3740.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e3846.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e3759.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e3761.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e2148.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2136.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2146.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e2201.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e2158.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e2161.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e6670.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e6667.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e6655.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e6665.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e6623.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e6628.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e5059.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5035.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5039.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e5066.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e5047.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e5043.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e5440.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e5452.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e5451.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e5605.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e5482.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e5481.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab4\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 4\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eStability test results of six silymarins (n\\u0026thinsp;=\\u0026thinsp;6)\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"8\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003esilymarins\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"6\\\" nameend=\\\"c7\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003epeak areas\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003eRSD(%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e5\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e6\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilychristin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1415.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1420.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1415.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1438.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e1445.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1447.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilydianin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e413.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e422.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e418.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e407.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e410.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e415.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1467.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1420.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1416.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1506.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e1512.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1523.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e3.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e2013.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2023.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2022.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e2112.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e2123.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e2129.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e2.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e499.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e502.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e503.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e503.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e507.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e509.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e306.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e301.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e323.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e319.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e320.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e324.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e3.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab5\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 5\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eRepeatability test results of six silymarins (n\\u0026thinsp;=\\u0026thinsp;6)\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"8\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003esilymarins\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"6\\\" nameend=\\\"c7\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003epeak areas\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c8\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003eRSD(%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e5\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e6\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilychristin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1549.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1514.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1518.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1521.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e1560.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1532.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilydianin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e506.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e479.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e477.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e481.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e497.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e489.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e2.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1515.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1579.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1583.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1597.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e1645.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1615.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e2.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e2238.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e2247.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2276.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e2275.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e2242.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e2295.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e612.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e636.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e644.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e643.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e664.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e649.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e2.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e338.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e341.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e342.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e342.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e351.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e356.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e2.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec19\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.4 Recovery rate\\u003c/h2\\u003e \\u003cp\\u003eAs the content of these six types of silymarins in milk thistle extracts is generally above 1%, this study used constant spiked levels (20%, 40%, and 60% of the sample amount) to spike actual samples. After three parallel experiments, the results of the recovery experiments for the samples were shown in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab6\\\" class=\\\"InternalRef\\\"\\u003e6\\u003c/span\\u003e. As can be seen from the table, each type of silymarins maintained good recovery rates at the three spiked levels, ranging between 92% and 108%, with RSDs less than 4%, which meets the quality control requirements for food physical and chemical testing in GB/T 27404 \\u003csup\\u003e[\\u003cspan citationid=\\\"CR30\\\" class=\\\"CitationRef\\\"\\u003e30\\u003c/span\\u003e]\\u003c/sup\\u003e. The method has good recoveries. This result indicates that the established detection method in this study has high recoveries and good precision under different spiked levels, and can meet the requirements for detecting six types of silymarins in actual samples.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab6\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 6\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eRecovery results of six silymarins in actual samples (n\\u0026thinsp;=\\u0026thinsp;3)\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"8\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c8\\\" colnum=\\\"8\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003esilymarins\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c3\\\" namest=\\\"c2\\\"\\u003e \\u003cp\\u003eSpiked level (20% sample)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c5\\\" namest=\\\"c4\\\"\\u003e \\u003cp\\u003eSpiked level (40% sample)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c7\\\" namest=\\\"c6\\\"\\u003e \\u003cp\\u003eSpiked level (60% sample)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"1\\\" nameend=\\\"c8\\\" namest=\\\"c8\\\"\\u003e\\u0026nbsp;\\u003c/th\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eRecovery rate (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eRSD\\u003csub\\u003er\\u003c/sub\\u003e (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eRecovery rate (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eRSD\\u003csub\\u003er\\u003c/sub\\u003e (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eRecovery rate (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003eRSD\\u003csub\\u003er\\u003c/sub\\u003e (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colspan=\\\"1\\\" nameend=\\\"c8\\\" namest=\\\"c8\\\"\\u003e\\u0026nbsp;\\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eSilychristin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e92.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e96.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e1.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e103.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eSilydianin\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e97.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e108.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e3.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e100.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e3.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e99.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e0.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e100.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e0.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e93.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eSilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e93.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e1.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e92.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e0.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e93.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e0.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin A\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e95.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e93.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e3.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e101.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e1.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colspan=\\\"2\\\" nameend=\\\"c2\\\" namest=\\\"c1\\\"\\u003e \\u003cp\\u003eIsosilybin B\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e92.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e92.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e3.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e93.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c8\\\"\\u003e \\u003cp\\u003e3.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec20\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003e3.5 Actual sample determination\\u003c/h2\\u003e \\u003cp\\u003eThe content of 6 silymarins in 42 milk thistle extract samples was analyzed and measured based on the method described in the paper, and the results were summarized in Table\\u0026nbsp;\\u003cspan refid=\\\"Tab7\\\" class=\\\"InternalRef\\\"\\u003e7\\u003c/span\\u003e. As shown in the table, there were significant differences in the content of the six silymarins corresponding to different products, which were related to the raw materials and production processes used in each product. Therefore, this also laid a solid foundation for formulating quality standards for silymarin extracts.\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab7\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 7\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eContents of six silymarins in actual samples (n\\u0026thinsp;=\\u0026thinsp;3)\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"7\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c7\\\" colnum=\\\"7\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e#\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eSilybin A (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eSilybin B (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eIsosilybin A (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eIsosilybin B (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eSilychristin (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003eSilydianin (%)\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e12.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e18.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e9.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e11.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e17.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e8.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e0.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e11.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e17.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e8.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e12.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e19.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e8.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e11.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e17.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.5\\u003c/p\\u003e \\u003c/td\\u003e 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colname=\\\"c1\\\"\\u003e \\u003cp\\u003e18\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e10.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e15.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e9.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e2.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e19\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e11.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e18.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e9.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e2.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e20\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e9.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e15.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.3\\u003c/p\\u003e \\u003c/td\\u003e 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colname=\\\"c1\\\"\\u003e \\u003cp\\u003e23\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e9.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e14.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e8.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e24\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e11.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd 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colname=\\\"c1\\\"\\u003e \\u003cp\\u003e28\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e12.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e21.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e4.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e13.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e29\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e13.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e21.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e4.5\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e12.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e30\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e14.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e21.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e3.2\\u003c/p\\u003e \\u003c/td\\u003e 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colname=\\\"c1\\\"\\u003e \\u003cp\\u003e33\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e9.6\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e15.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.1\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e9.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e34\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e13.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e21.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e4.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e1.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e11.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e1.9\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e35\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e9.0\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e13.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2.7\\u003c/p\\u003e \\u003c/td\\u003e 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colname=\\\"c1\\\"\\u003e \\u003cp\\u003eRange\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e2.3\\u0026thinsp;~\\u0026thinsp;18.3\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e7.1\\u0026thinsp;~\\u0026thinsp;21.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003e2.7\\u0026thinsp;~\\u0026thinsp;5.8\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e0.8\\u0026thinsp;~\\u0026thinsp;2.2\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003e7.9\\u0026thinsp;~\\u0026thinsp;15.4\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c7\\\"\\u003e \\u003cp\\u003e0.8\\u0026thinsp;~\\u0026thinsp;6.7\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"4. Conclusions\",\"content\":\"\\u003cp\\u003eThis paper established a HPLC method for the detection of six silymarins in milk thistle extracts by optimizing the mobile phase composition and gradient conditions based on several standard methods. Under the optimal analytical conditions, the six silymarins compounds in the milk thistle extract can achieve good baseline separation from the matrix with good resolution. At the same time, the limit of detection of this method was 25 mg/kg, and the RSDs of repeatability and stability were \\u0026lt;\\u0026thinsp;3.2%. The recovery rates at three spiking levels ranged from 92\\u0026ndash;108%, and the RSDs were \\u0026lt;\\u0026thinsp;4%. This method had good sensitivity, repeatability, and accuracy and can be used for the analysis of actual samples. Through testing 42 batches of milk thistle extract samples, it was found that there were significant differences in the content of the six silymarins corresponding to different products. The establishment of this method provided a foundation for testing methods and data that can be used to develop quality standards for milk thistle extracts, and it plays an important role in promoting the high-quality development of plant extract industry.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eDeclaration of interest\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe authors declare that there is no conflict of interest. The authors alone are responsible for the accuracy and integrity of the paper content.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthical approval\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThis article did not involve animal experiments, so there was no need for ethical examination.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthor Contribution\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eConceptualization, project administration, data curation, supervision, T.L.; methodology, writing original draft preparation, data curation, Z.W.Y.; methodology, data curation, Z.Q.; investigation, data curation, H.J.L.; data curation, Y.C.C.; writing-review and editing, L.S.H.; writing-review and editing, Z.X.; supervision, H.R.Q. All authors have read and agreed to the published version of the manuscript.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\n\\u003cli\\u003ePickoval D, Ostry V, Toman J, Malir F (2020) Toxins (Basel) 12(12): 782.\\u003c/li\\u003e\\n\\u003cli\\u003eAssociation Standards Committee of China Industry-University-Research Institute Collaboration Association (2023) Quality Requirements of Milk Thistle Extract (T/CAB 0277-2023). Beijing: Standards Press of China.\\u003c/li\\u003e\\n\\u003cli\\u003eFanoudi S, Alavi MS, Karimi G, Hosseinzadeh H (2020) Drug Chemi Toxicol 43(3): 240-254.\\u003c/li\\u003e\\n\\u003cli\\u003eRoss SM, (2008) Holist Nurs Pract 22(5): 299-300.\\u003c/li\\u003e\\n\\u003cli\\u003eSoleimani V, Delghandi PS, Moallem SA, Karimi G (2019) Phytother Res 33(6): 1627-1638.\\u003c/li\\u003e\\n\\u003cli\\u003eAbenacoli L, Izzo AA, Milic N, Cicala C, Santini A, Capasso R (2018) Phytother Res 2(11): 2202-2213.\\u003c/li\\u003e\\n\\u003cli\\u003eVaid M, Katiy SK (2010) Int J Oncol 36(5): 1053-60.\\u003c/li\\u003e\\n\\u003cli\\u003eSaurat JH, Reygagne P, Josse G, Hamidou Z, Bianovici S, Ramel F, Durbise E, Lovati C, Bellani E, Bystrzanowska D, Chlebus E, Kowalska-Oledzka E, D\\u0026rsquo;Auzers G, Digabel JL, Filiol J, Lauze C, Ortiz-Brugues A, Nocera T (2022) J Pers Med 13(1): 96.\\u003c/li\\u003e\\n\\u003cli\\u003eHoh CSL, Boocock DJ, Marczylo TH, Brown VA, Cai H, Steward WP, Berry DP, Gescher AJ (2007) J Agric Food Chem 55(7): 2532-2535.\\u003c/li\\u003e\\n\\u003cli\\u003eNational Pharmacopoeia Commission. Pharmacopoeia of the People\\u0026apos;s Republic of China, (2020) 1 Volumes. Beijing: China Medical Science and Technology Press, 84.\\u003c/li\\u003e\\n\\u003cli\\u003eEuropean Pharmacopoeia 10.6. (2022) Milk Thistle Dry Extract, Refined and Standardised (Silybi mariani extractum siccum raffinatum et normatum). 2071.\\u003c/li\\u003e\\n\\u003cli\\u003eUnited States Pharmacopoeia. Powdered Milk Thistle Extract. USP35\\u0026ndash;NF30, 1387.\\u003c/li\\u003e\\n\\u003cli\\u003eAssociation Standards Committee of China Chamber of Commerce of Medicine \\u0026amp;Health Products Importers \\u0026amp; Exporters (2016) Plant extract-Milk thistle extract (Active Pharmaceutical Ingredient) (T/CCCMHPIE 1.21\\u0026mdash;2016). Beijing: Standards Press of China.\\u003c/li\\u003e\\n\\u003cli\\u003eLee JI, Narayan M, Barrett JS (2007) J Chromatogra B 845(1): 95-103.\\u003c/li\\u003e\\n\\u003cli\\u003eQuaglia M, Bossu E, Donati E, Mazzanti G, Brandt A (1999) J Pharmaceut Biomed 19(3-4): 435-442. \\u003c/li\\u003e\\n\\u003cli\\u003eCheilari A, Sturm S, Intelmann D, Seger C, Stuppner H (2016) J Agric Food Chem 64(7): 1618-1626.\\u003c/li\\u003e\\n\\u003cli\\u003eRadjabian T, Rezazadeh SH, Huseini HF (2008) Iran J Sci Technol A 32(A2): 141-146.\\u003c/li\\u003e\\n\\u003cli\\u003eTayoub G, Sulaiman H, Alorifi M (2018) Int J Herb Med 6(2): 110-114. \\u003c/li\\u003e\\n\\u003cli\\u003eMhamdi B, Abbassi F, Smaoui A, Abdelly C, Marzouk B (2016) Pak J Pharm Sci 29(3): 953-959. \\u003c/li\\u003e\\n\\u003cli\\u003ePadma M, Ganesan S, Jayaseelan T, Azhagumadhavan S, Sasikala P, Senthilkumar S, Mani P (2019) J Drug Deliv The 9(1): 85-89.\\u003c/li\\u003e\\n\\u003cli\\u003eTajabadi F, Ghorbanin-Ohooji M, Gholami A, Yekta MG, Ghasemi SV, Nabati F, Sadri SH (2023) Biomed. Chromatogra. 37(3): e5566.\\u003c/li\\u003e\\n\\u003cli\\u003eLazzeroni M, Petrangolini G, Iriberri JAL, Avellana JP, Robuste DT, Cagnacci S, Macis D, Aristarco V, Bonanni B, Morazzoni P, Johansson H, Riva A (2020) Molecules 25(12): 2918.\\u003c/li\\u003e\\n\\u003cli\\u003eKuki A, Nagy L, Deak G, Nagy M, Zsuga M, Keki S (2012) Chromatographia 75: 175-180.\\u003c/li\\u003e\\n\\u003cli\\u003eMuchiri RN, Van Breemen RB (2021) J AOAC Int 104(1): 232-238.\\u003c/li\\u003e\\n\\u003cli\\u003eRiasov\\u0026aacute; P, Jenčo J, Moreno-Gonz\\u0026aacute;lez D, Heyden YV, Mangelings D, Pol\\u0026aacute;\\u0026scaron;ek M, J\\u0026aacute;č P (2022) Electrophoresis 43(9-10): 930-938.\\u003c/li\\u003e\\n\\u003cli\\u003eLu HY, Guan J, Yan F (2021) Mod Chem Resear 50(01): 240-243.\\u003c/li\\u003e\\n\\u003cli\\u003eNotice of the State Administration of Market Regulation on Issuing the \\u0026quot;Regulations on the Management of Supplementary Inspection Methods for Food\\u0026quot;. (2023-03-07).\\u003c/li\\u003e\\n\\u003cli\\u003eUS FDA Guidance for Industry (2018) Bioanalytical Method Validation. Silver Spring, MD.\\u003c/li\\u003e\\n\\u003cli\\u003eAppendix K (2013) Guidelines for Dietary Supplements and Botanicals. AOAC Int. Gaithersburg, MD.\\u003c/li\\u003e\\n\\u003cli\\u003eGB/T 27404 (2008) Criterion on quality control of laboratories-Chemical testing of food., Beijing: Standards Press of China.\\u003c/li\\u003e\\n\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":true,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"researchsquare\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":true,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"/submission\",\"title\":\"Research Square\",\"twitterHandle\":\"researchsquare\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":false,\"inReviewRevisionsEnabled\":true},\"keywords\":\"powdered milk thistle extract, silymarin, high performance liquid chromatography (HPLC), quality control\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-3828831/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-3828831/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003cp\\u003eThis study aims to develop a user-friendly and efficient high-performance liquid chromatography method for the detection of six silymarin in powdered milk thistle extract. On the basis of existing standard methods, a simpler prepared mobile phase was used, and the gradient program of mobile phase was optimized. The effectiveness of this method was verified through methodological investigations such as instrument precision experiments, stability experiments, repeatability experiments, and spiked recovery experiments. The method was applied to the detection of 42 batches of actual samples of powdered milk thistle extract. Under optimized mobile phase and gradient elution conditions, six silymarin compounds in powdered milk thistle extract could be effectively separated from the matrix with baseline resolution. There was a good linear relationship between the concentration of the six silymarin compounds in the range of 5~150 μg/mL, with a limit of detection (LOD) of 25 mg/kg. The precision, stability, and repeatability of the method were all below 5%, and the recovery rates at three spiked levels range from 92% to 108%, with RSDs below 4%, indicating its excellent precision and stability. This method was user-friendly and efficient, with good accuracy, making it suitable for the analysis and detection of real samples. During the actual sample testing, significant variations were observed in the content of the six silymarin compounds among different products. The establishment of this method can be utilized for quality control of powdered milk thistle extract products.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Development of a determination method for six silymarin in powdered milk thistle extract\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2024-01-08 06:24:06\",\"doi\":\"10.21203/rs.3.rs-3828831/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"researchsquare\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":true,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"/submission\",\"title\":\"Research Square\",\"twitterHandle\":\"researchsquare\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":false,\"inReviewRevisionsEnabled\":true}}],\"origin\":\"\",\"ownerIdentity\":\"ddb99154-5c38-4803-9665-312a337b9d13\",\"owner\":[],\"postedDate\":\"January 8th, 2024\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"posted\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2024-01-10T15:14:17+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2024-01-08 06:24:06\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-3828831\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-3828831\",\"identity\":\"rs-3828831\",\"version\":[\"v1\"]},\"buildId\":\"qtupq5eGEP_6zYnWcrvyt\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}