{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T13:41:43Z","timestamp":1788356503957,"version":"build-2803163510"},"reference-count":50,"publisher":"MDPI AG","issue":"20","license":[{"start":{"date-parts":[[2019,10,15]],"date-time":"2019-10-15T00:00:00Z","timestamp":1571097600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008816","name":"University of Sri Jayewardenepura","doi-asserted-by":"publisher","award":["ASP\/01\/RE\/SCI\/2017\/50"],"award-info":[{"award-number":["ASP\/01\/RE\/SCI\/2017\/50"]}],"id":[{"id":"10.13039\/501100008816","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Obesity and diabetes are major metabolic disorders which are prevalent worldwide. Algae has played an important role in managing these disorders. In this study, Gracilaria edulis, a marine red algae, was investigated for antioxidant and hypoglycemic potential using in vitro models. De-polysaccharide methanol extract of G. edulis was sequentially partitioned with hexane, chloroform, ethyl acetate, and antioxidants, and hypoglycemic potentials were evaluated using multiple methods. High antioxidant potential was observed in the ethyl acetate fraction in terms of ferric reducing antioxidant power, iron chelating, and DPPH and ABTS radical scavenging activities, while the crude methanol extract exhibited potent oxygen radical-absorbance capacity. Potent \u03b1-amylase inhibitory activity was observed in the ethyl acetate fraction, while the ethyl acetate fraction was effective against \u03b1-glucosidase inhibition. Glucose diffusion was inhibited by the ethyl acetate fraction at 180 min, and the highest antiglycation activity was observed in both chloroform and ethyl acetate fractions. Additionally, gas chromatography-mass spectrometry analysis of the ethyl acetate fraction revealed the presence of several potent anti-diabetic compounds. In conclusion, G. edulis exhibited promising antidiabetic potential via multiple mechanisms. The ethyl acetate fraction exhibited the strongest hypoglycemic and antiglycation potential among the four fractions, and hence the isolation of active compounds is required to develop leads for new drugs to treat diabetes.<\/jats:p>","DOI":"10.3390\/molecules24203708","type":"journal-article","created":{"date-parts":[[2019,10,16]],"date-time":"2019-10-16T03:32:54Z","timestamp":1571196774000},"page":"3708","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":75,"title":["In-Vitro Antioxidant, Hypoglycemic Activity, and Identification of Bioactive Compounds in Phenol-Rich Extract from the Marine Red Algae Gracilaria edulis (Gmelin) Silva"],"prefix":"10.3390","volume":"24","author":[{"given":"Thilina L.","family":"Gunathilaka","sequence":"first","affiliation":[{"name":"Department of Zoology, Faculty of Applied Sciences (Center for Instrumentation Facility &amp; Center for Biotechnology), University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kalpa W.","family":"Samarakoon","sequence":"additional","affiliation":[{"name":"National Science and Technology Commission, Dudley Senanayake Mawatha, Colombo 8 00800, Sri Lanka"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"P.","family":"Ranasinghe","sequence":"additional","affiliation":[{"name":"Industrial Technology Institute, Halbarawa Gardens, Malabe 10115, Sri Lanka"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4788-6852","authenticated-orcid":false,"given":"L. Dinithi C.","family":"Peiris","sequence":"additional","affiliation":[{"name":"Department of Zoology, Faculty of Applied Sciences (Center for Instrumentation Facility &amp; Center for Biotechnology), University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"American Diabetes Association (2013). Diagnosis and classification of diabetes mellitus. Diab. Care, 36, 67\u201374.","DOI":"10.2337\/dc13-S067"},{"key":"ref_2","unstructured":"World Health Organization (2019, January 31). Available online: http:\/\/www.who.int\/mediacentre\/factsheets\/fs312\/en\/."},{"key":"ref_3","first-page":"1","article-title":"Diabetes susceptibility in ethnic minority groups from Turkey, Vietnam, Sri Lanka and Pakistan compared with Norwegians - the association with adiposity is strongest for ethnic minority women","volume":"12","author":"Jenum","year":"2012","journal-title":"BMC Pub. Heal."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"546","DOI":"10.4103\/2230-8210.183480","article-title":"Microvasular and macrovascular complications in diabetes mellitus: Distinct or continuum","volume":"20","author":"Chawla","year":"2016","journal-title":"Indian J. Endocrinol. Metab."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"468","DOI":"10.4314\/ahs.v16i2.15","article-title":"The concept of low glycemic index and glycemic load foods as panacea for type 2 diabetes mellitus","volume":"16","author":"Eleazu","year":"2016","journal-title":"Afr. Health Sci."},{"key":"ref_6","first-page":"128","article-title":"In vitro studies on alpha amylase and alpha glucosidase inhibitory activities of selected plant extracts","volume":"3","author":"Nair","year":"2013","journal-title":"Eur. J. Exp. Biol."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Fern\u00e11ndez-S\u00e1nchez, A., Madrigal-Santill\u00e1n, E., Bautista, M., Esquivel-Soto, J., Morales-Gonz\u00e1lez, A., Esquivel-Chirino, C., Durante-Montiel, I., S\u00e1nchez-Rivera, G., Valadez-Vega, C., and Morales-Gonz\u00e1lez, J.A. (2011). Inflammation, Oxidative Stress, and Obesity. Int. J. Mol. Sci., 12, 3117\u20133132.","DOI":"10.3390\/ijms12053117"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"308","DOI":"10.1111\/j.1368-5031.2006.00825.x","article-title":"Oxidative stress in type 2 diabetes: The role of fasting and postprandial glycaemia","volume":"60","author":"Wright","year":"2006","journal-title":"Int. J. Clin. Pract."},{"key":"ref_9","first-page":"1","article-title":"Bioactive Compounds and Properties of Seaweeds\u2014A Review","volume":"1","author":"Pal","year":"2014","journal-title":"Biotechnol. Bioinform."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"4550","DOI":"10.3390\/ijms12074550","article-title":"Bioactivities from Marine Algae of the Genus Gracilaria","volume":"12","author":"Batista","year":"2011","journal-title":"Int. J. Mol. Sci."},{"key":"ref_11","first-page":"117","article-title":"Preliminary screening of two marine algae and sea grass harvested from Sri Lankan waters against the LPS-induced inflammatory responses in RAW 264.7 macrophages and in vivo Zebra fish embryo model","volume":"46","author":"Fernando","year":"2018","journal-title":"J. Natl. Sci. Found."},{"key":"ref_12","first-page":"154","article-title":"A Study on the Type II Antidiabetic Activity of Methanolic Extract of Marine Algae, Gracilaria edulis and Sargassum polycystum","volume":"47","author":"Koneri","year":"2017","journal-title":"Int. J. Pharm. Sci. Rev. Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"331","DOI":"10.1186\/1472-6882-13-331","article-title":"Gracilaria edulis extract induces apoptosis and inhibits tumor in Ehrlich Ascites tumor cells in vivo","volume":"13","author":"Patra","year":"2013","journal-title":"BMC Complementary Altern. Med."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"2812","DOI":"10.5897\/AJB2015.14956","article-title":"Analysis of bioactive chemical components of two medicinal plants (Coriandrum sativum and Melia azedarach) leaves using gas chromatography-mass spectrometry (GC-MS)","volume":"14","author":"Hameed","year":"2015","journal-title":"Afr. J. Biotchenol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"1167","DOI":"10.1021\/acs.jafc.7b06008","article-title":"Anti-Inflammatory and Antioxidant Activities from the Basolateral Fraction of Caco-2 Cells Exposed to a Rosmarinic Acid Enriched Extract","volume":"66","author":"Villalva","year":"2018","journal-title":"J. Agric. Food Chem."},{"key":"ref_16","first-page":"237","article-title":"GC-MS analysis of Calendula officinalis and cytotoxic effects of its flower crude extract on human epidermoid larynx carcinoma (hep-2)","volume":"3","author":"Jalill","year":"2014","journal-title":"World J. Pharm. Pharm. Sci."},{"key":"ref_17","first-page":"1","article-title":"Chemistry and Biology of Indoles and Indazoles: A Mini-Review","volume":"13","author":"Ali","year":"2012","journal-title":"Med. Chem."},{"key":"ref_18","unstructured":"World Intellectual Property Organization (2011). Indole and Indazole derivatives as glycogen synthase activators. Int. Appl. Publ. Under Pat. Coop. Treaty, 74, 1\u201310."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1099\/jmm.0.077768-0","article-title":"In vitro antifungal activity and mechanism of essential oil from fennel (Foeniculum vulgare L.) on dermatophyte species","volume":"64","author":"Zeng","year":"2015","journal-title":"J. Med. Microbiol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1170","DOI":"10.1007\/s00044-010-9457-4","article-title":"Synthesis and structure-antibacterial activity relationship studies of 4-substituted phenyl -4, 5-dihydrobenzo [f] [1, 4] oxazepin-3 (2H)-thiones","volume":"20","author":"Agirbas","year":"2011","journal-title":"Med. Chem. Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"399","DOI":"10.1016\/j.sjbs.2015.10.026","article-title":"Characteristics of antibacterial molecular activities in poplar wood extractives","volume":"24","author":"Peng","year":"2017","journal-title":"Saudi J. Biol. Sci."},{"key":"ref_22","first-page":"270","article-title":"Plant polyphenols as dietary antioxidants in human health and disease","volume":"2","author":"Pandey","year":"2009","journal-title":"J. Clin. Investig."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2717","DOI":"10.1016\/j.biortech.2007.07.005","article-title":"Antioxidant properties of methanol extract and its solvent fractions obtained from selected Indian red seaweeds","volume":"99","author":"Ganesan","year":"2008","journal-title":"Bioresour. Technol."},{"key":"ref_24","first-page":"4451","article-title":"Seasonal variations in the phenolic compound content and antioxidant activities of three selected species of seaweeds from Tiskerth islet, Bejaia, Algeria","volume":"8","author":"Fellah","year":"2017","journal-title":"J. Mater. Environ. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"378","DOI":"10.3390\/ijms16010378","article-title":"Oxidative Stress in Obesity: A Critical Component in Human Diseases","volume":"16","author":"Marseglia","year":"2015","journal-title":"Int. J. Mol. Sci."},{"key":"ref_26","first-page":"342","article-title":"In vitro anti-diabetic, antioxidant and anti- inflammatory activity of Clitoria Ternatea, L.","volume":"6","author":"Sampath","year":"2014","journal-title":"Artic. Int. J. Pharm. Pharm. Sci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"3754","DOI":"10.3390\/md11103754","article-title":"The red seaweed Gracilaria gracilis as a multi products source","volume":"11","author":"Francavilla","year":"2013","journal-title":"Mar. Drugs"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"117","DOI":"10.4038\/tar.v23i2.4643","article-title":"Antioxidant Activity of Caryota urens L. (Kithul) Sap","volume":"23","author":"Ranasinghe","year":"2012","journal-title":"Trop. Agric. Res."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"669","DOI":"10.1016\/j.foodchem.2012.02.159","article-title":"Antioxidant capacity, total phenolic and ascorbate content as a function of the genetic diversity of leek (Allium ampeloprasum var porrum)","volume":"134","author":"Bernaert","year":"2012","journal-title":"Food Chem."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1186\/1472-6882-12-77","article-title":"Enzyme inhibitory and antioxidant activities of traditional medicinal plants: Potential application in the management of hyperglycemia","volume":"12","author":"Gulati","year":"2012","journal-title":"Bmc Complementary Altern Med."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1080\/21553769.2015.1005244","article-title":"Antidiabetic potential of marine algae by inhibiting key metabolic enzymes","volume":"8","author":"Unnikrishnan","year":"2015","journal-title":"J. Front. Life Sci."},{"key":"ref_32","first-page":"128","article-title":"Evaluation of Alpha-Amylase and Alpha-Glucosidase Inhibitory Properties of Selected Seaweeds from Gulf of Mannar","volume":"3","author":"Sudha","year":"2012","journal-title":"Irjponline. Com."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1016\/S0271-5317(02)00533-X","article-title":"The effects of traditional antidiabetic plants on in vitro glucose diffusion","volume":"23","author":"Gallagher","year":"2003","journal-title":"Nutr. Res."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Sudasinghe, H.P., and Peiris, D.C.P. (2018). Hypoglycemic and hypolipidemic activity of aqueous leaf extract of Passiflora suberosa L.. Peer J., 6.","DOI":"10.7717\/peerj.4389"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1007\/s12551-015-0186-2","article-title":"Glucose transporters: physiological and pathological roles","volume":"8","author":"Navale","year":"2016","journal-title":"Biophys Rev."},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Grzegorczyk-Karolak, I., Go\u0142a, G., Gburek, J., Wysokin, H., and Matkowski, A. (2016). Inhibition of Advanced Glycation End-Product Formation and Antioxidant Activity by Extracts and Polyphenols from Scutellaria alpina L. and S. altissima L.. Molecules, 21.","DOI":"10.3390\/molecules21060739"},{"key":"ref_37","first-page":"117","article-title":"Anticancer and antioxidant effects of selected Sri Lankan marine algae","volume":"42","author":"Lakmal","year":"2014","journal-title":"J. Natl. Sci. Found. Sri Lanka"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1016\/S0076-6879(99)99017-1","article-title":"Analysis of total phenols and other oxidation substrates and antioxidants by means of Folin-Ciocaltue reagent","volume":"299","author":"Singleton","year":"1999","journal-title":"Methods Enzym."},{"key":"ref_39","first-page":"178","article-title":"Estimation of total flavonoid content in propolis by complementary colorimetric method","volume":"10","author":"Chang","year":"2002","journal-title":"J. Food Drug Anal."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1124","DOI":"10.1093\/jaoac\/86.6.1124","article-title":"Spectrometric method for estimation of precipitable with Dragendorff\u2019s reagent in plant material","volume":"36","author":"Sreevidya","year":"2003","journal-title":"J. Aoac Int."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1199","DOI":"10.1038\/1811199a0","article-title":"Antioxidant determination by use of stable free radical","volume":"181","author":"Blois","year":"1958","journal-title":"Nature"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"1231","DOI":"10.1016\/S0891-5849(98)00315-3","article-title":"Antioxidant activity applying an improved ABTS radical cation decolorization Assay","volume":"26","author":"Re","year":"1999","journal-title":"Free Rad. Biol. Med"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"633","DOI":"10.1021\/jf9807768","article-title":"Total antioxidant capacity of teas by the ferric reducing\/antioxidant power assay","volume":"47","author":"Benzie","year":"1999","journal-title":"J. Agric. Food Chem."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"450","DOI":"10.1016\/0003-2697(71)90405-2","article-title":"Spectrophotometric determination of serum iron at the sub-microgram level with a new reagent ferrozine","volume":"40","author":"Carter","year":"1971","journal-title":"Annu. Biochem."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"4619","DOI":"10.1021\/jf010586o","article-title":"Development and validation of an improved oxygen radical absorbance capacity assay using fluorescein as the fluorescent probe","volume":"49","author":"Ou","year":"2001","journal-title":"J. Agric. Food Chem."},{"key":"ref_46","first-page":"149","article-title":"Amylases, alpha and beta","volume":"Volume 1","author":"Colowick","year":"1955","journal-title":"Methods in Enzymology"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"1948","DOI":"10.1021\/jf001251u","article-title":"\u03b1-Glucosidase inhibitory action of natural acylated anthocyanins","volume":"49","author":"Matsui","year":"2001","journal-title":"J. Agric. Food Chem."},{"key":"ref_48","first-page":"884","article-title":"The in-vitro antidiabetic activity of Phoenix roebelenii leaf extract","volume":"11","author":"Roy","year":"2017","journal-title":"Int. J. Green Pharm."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"520","DOI":"10.1248\/jhs.48.520","article-title":"Screening system for the Maillard reaction inhibitor from natural product extracts","volume":"48","author":"Matsuura","year":"2002","journal-title":"J. Health Sci."},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Jerkovi, I. (2008). Phytochemical study of the headspace volatile organic compounds of fresh algae and sea grass from the Adriatic Sea (single point collection). PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0196462"}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/24\/20\/3708\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:26:38Z","timestamp":1760189198000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/24\/20\/3708"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,10,15]]},"references-count":50,"journal-issue":{"issue":"20","published-online":{"date-parts":[[2019,10]]}},"alternative-id":["molecules24203708"],"URL":"https:\/\/doi.org\/10.3390\/molecules24203708","relation":{},"ISSN":["1420-3049"],"issn-type":[{"value":"1420-3049","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,10,15]]}}}