Metabarcoding Combined with Specific Mini-barcodes Enables Qualitative and Quantitative Analysis of Traditional Chinese Medicine: A Case Study of Lonicerae japonicae flos

Abstract BACKGROUND: Lonicerae japonicae flos, also known as Jinyinhua (JYH), is an important component of traditional Chinese patent medicine (TCPM) products. However, the potential for adulteration and substitution with low-quality materials highlights the need for a reliable and sensitive approach to identify the species composition of TCPM products for consumer safety. METHODS AND RESULTS: We used universal ITS2 primers to amplify TCPMs containing JYH. However, the results were inconclusive, as only one operational taxonomic unit (OTU) was identified as Lonicera sp., which could not be identified at the species level. To confirm the species identification of Lonicera sp. in TCPM, we developed a short mini-barcode primer based on thepsbA-trnH region, which, in combination with DNA metabarcoding technology, allowed for qualitative and quantitative analysis of artificially mixed samples. We applied the mini-barcode to distinguish TCPMs containing JYH and demonstrated its relatively accurate quantitative ability in identifying twoLonicera species. CONCLUSIONS: Our study presents a method for qualitative and quantitative identification of JYH, providing a promising application of DNA metabarcoding technology in the quality control of TCPM products.