Influence of acetylation and carboxymethylation on physicochemical characteristics of glucan exopolysaccharide isolated from Enterococcus hirae OL616073

Influence of acetylation and carboxymethylation on physicochemical characteristics of glucan exopolysaccharide isolated from Enterococcus hirae OL616073 | 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 Influence of acetylation and carboxymethylation on physicochemical characteristics of glucan exopolysaccharide isolated from Enterococcus hirae OL616073 Irshad Ahmad Shah, Swati Tiwari, Palanisamy Bruntha Devi, Digambar Kavitake, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6483162/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 13 You are reading this latest preprint version Abstract Chemical modifications such as acetylation and carboxymethylation significantly influence the physicochemical properties of biopolymers, including exopolysaccharides (EPS). In this study, glucan EPS from Enterococcus hirae OL616073 was chemically modified to acetylated glucan (AG) and carboxymethylated glucan (CG) via an affordable process. The structure and properties were investigated by 1 H NMR spectroscopy, Fourier transform infrared (FTIR), scanning electron microscope (SEM), contact angle, particle size, thermal analysis (TGA-DSC), and X-ray diffractometer (XRD). The results demonstrated the effect of modification on its physicochemical properties. As L* varied between 70.13 to 74.46 with a mild darkening effect in the acetylated derivative than carboxymethylated, a* ranged from 3.55–3.87, affirming the reddish tint in all the powders. There was a slight increase (70.24) in whiteness index (WI) for CG in comparison to AG (68.10) and Untreated (UT) (65.23). Decrease in bulk density (0.532 to 0.415 g/mL), tapped density (0.756 to 0.531g/mL), Hausner ratio (1.42 to 1.27), and compressibility index (CI) (29.61 to 21.81%) from UT to CG was observed. Micrographs revealed a significant change from agglomerated granules in AC to rough and collapsed granules in CG. Water activity (a w ) of untreated glucan decreased from 0.358 to 0.345 in AG and further increased to 0.380 for CG. The particle size of untreated glucan (226.6 nm) increased to 365.8 nm in AG and 526.4 nm in CG. Acetylation enhanced hydrophobicity (water contact angle: 56.58° to 66.28°), while CG became more hydrophilic (44.13°). Water holding capacity increased from 328.11% (UT) to 494.22% (CG). The emulsion stability of acetylated glucan retained better at different time intervals. Furthermore, CG showed significant antitumor effects against HCT116 cells (8.18 to 47.04% reduction) than AG (2.04 to 17.22%) at 25–500 µg/mL. The findings highlight the influence of functional groups and reaction conditions on EPS properties, suggesting their potential in functional food development. Enterococcus hirae OL616073 acetylated glucan carboxymethylated glucan Physico-functional properties anticolon cancer activity Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 13 May, 2025 Reviews received at journal 13 May, 2025 Reviews received at journal 09 May, 2025 Reviewers agreed at journal 07 May, 2025 Reviewers agreed at journal 05 May, 2025 Reviewers agreed at journal 05 May, 2025 Reviews received at journal 01 May, 2025 Reviewers agreed at journal 01 May, 2025 Reviewers agreed at journal 01 May, 2025 Reviewers invited by journal 01 May, 2025 Editor assigned by journal 24 Apr, 2025 Submission checks completed at journal 24 Apr, 2025 First submitted to journal 19 Apr, 2025 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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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-6483162","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":452041457,"identity":"2588e9be-e2e0-49c1-b73f-8e983c1b7526","order_by":0,"name":"Irshad Ahmad Shah","email":"","orcid":"","institution":"Pondicherry University","correspondingAuthor":false,"prefix":"","firstName":"Irshad","middleName":"Ahmad","lastName":"Shah","suffix":""},{"id":452041458,"identity":"cbe02828-2f29-49e0-897a-37dc3e8bd7cc","order_by":1,"name":"Swati Tiwari","email":"","orcid":"","institution":"Pondicherry 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Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Enterococcus hirae OL616073, acetylated glucan, carboxymethylated glucan, Physico-functional properties, anticolon cancer activity","lastPublishedDoi":"10.21203/rs.3.rs-6483162/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6483162/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eChemical modifications such as acetylation and carboxymethylation significantly influence the physicochemical properties of biopolymers, including exopolysaccharides (EPS). In this study, glucan EPS from \u003cem\u003eEnterococcus hirae\u003c/em\u003e OL616073 was chemically modified to acetylated glucan (AG) and carboxymethylated glucan (CG) via an affordable process. The structure and properties were investigated by \u003csup\u003e1\u003c/sup\u003eH NMR spectroscopy, Fourier transform infrared (FTIR), scanning electron microscope (SEM), contact angle, particle size, thermal analysis (TGA-DSC), and X-ray diffractometer (XRD). The results demonstrated the effect of modification on its physicochemical properties. As L* varied between 70.13 to 74.46 with a mild darkening effect in the acetylated derivative than carboxymethylated, a* ranged from 3.55\u0026ndash;3.87, affirming the reddish tint in all the powders. There was a slight increase (70.24) in whiteness index (WI) for CG in comparison to AG (68.10) and Untreated (UT) (65.23). Decrease in bulk density (0.532 to 0.415 g/mL), tapped density (0.756 to 0.531g/mL), Hausner ratio (1.42 to 1.27), and compressibility index (CI) (29.61 to 21.81%) from UT to CG was observed. Micrographs revealed a significant change from agglomerated granules in AC to rough and collapsed granules in CG. Water activity (a\u003csub\u003ew\u003c/sub\u003e) of untreated glucan decreased from 0.358 to 0.345 in AG and further increased to 0.380 for CG. The particle size of untreated glucan (226.6 nm) increased to 365.8 nm in AG and 526.4 nm in CG. Acetylation enhanced hydrophobicity (water contact angle: 56.58\u0026deg; to 66.28\u0026deg;), while CG became more hydrophilic (44.13\u0026deg;). Water holding capacity increased from 328.11% (UT) to 494.22% (CG). The emulsion stability of acetylated glucan retained better at different time intervals. Furthermore, CG showed significant antitumor effects against HCT116 cells (8.18 to 47.04% reduction) than AG (2.04 to 17.22%) at 25\u0026ndash;500 \u0026micro;g/mL. The findings highlight the influence of functional groups and reaction conditions on EPS properties, suggesting their potential in functional food development.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e","manuscriptTitle":"Influence of acetylation and carboxymethylation on physicochemical characteristics of glucan exopolysaccharide isolated from Enterococcus hirae OL616073","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-06 18:21:21","doi":"10.21203/rs.3.rs-6483162/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-05-13T22:29:15+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-13T07:07:58+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-09T16:27:28+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"40202019693718522330882758088906228330","date":"2025-05-07T04:20:20+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"247103884552344035343651816194506045394","date":"2025-05-05T11:11:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"275093222240275215231420260734420435688","date":"2025-05-05T06:33:13+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-05-01T18:43:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"14286039956530493460822888940769727727","date":"2025-05-01T16:02:44+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"239441754336465677798212505708038876618","date":"2025-05-01T14:06:58+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-05-01T13:57:10+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-04-24T09:00:51+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-04-24T08:57:47+00:00","index":"","fulltext":""},{"type":"submitted","content":"Biotechnology for Sustainable Materials","date":"2025-04-19T07:17:14+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"biotechnology-for-sustainable-materials","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"Learn more about [Biotechnology for Sustainable Materials](https://biotechsustainablematerials.biomedcentral.com)","snPcode":"44316","submissionUrl":"https://submission.springernature.com/new-submission/44316/3","title":"Biotechnology for Sustainable Materials","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"fe0e427e-cdaf-4e27-829c-99fdf38cbc72","owner":[],"postedDate":"May 6th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-06-12T13:23:29+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-06 18:21:21","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6483162","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6483162","identity":"rs-6483162","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}