{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T18:49:14Z","timestamp":1790275754641,"version":"4.1.0"},"reference-count":46,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2019,3,13]],"date-time":"2019-03-13T00:00:00Z","timestamp":1552435200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003093","name":"Ministry of Higher Education, Malaysia","doi-asserted-by":"publisher","award":["Fundamental Grant Research Scheme (FRGS 16-042-0541)"],"award-info":[{"award-number":["Fundamental Grant Research Scheme (FRGS 16-042-0541)"]}],"id":[{"id":"10.13039\/501100003093","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007297","name":"International Islamic University Malaysia","doi-asserted-by":"publisher","award":["Research Initiative Grant Schemes (RIGS 16-294-0458)"],"award-info":[{"award-number":["Research Initiative Grant Schemes (RIGS 16-294-0458)"]}],"id":[{"id":"10.13039\/501100007297","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Digestive enzymes and free radical inhibitors are used to prevent complications resulting from diabetes. Entada spiralis (family Leguminosae), which is a well-known medicinal plant in herbal medicine due to its various traditional and medicinal applications, was studied. Crude extracts were successively obtained from the stem bark using petroleum ether, chloroform and methanol as extracting solvents. The antioxidant activity of all the extracts, fractions and isolated compounds were estimated using 2,2-diphenyl-1-picrylhydrazyl (DPPH), \u03b2-carotene and 2,2\u2032-azinobis(-3-ethylbenzothiazine-6-sulfonic acid) (ABTS) assays, while digestive enzymes inhibitory activity was assessed using \u03b1-amylase and \u03b1-glucosidase inhibitory methods. Structure elucidation of pure compounds was achieved through different spectroscopic analysis methods. Fractionation and purification of the most active methanol extract resulted in the isolation of a ferulic ester namely; (e)-hexyl 3-(4-hydroxy-3-methoxyphenyl) acrylate (FEQ-2) together with five known phenolic constituents, identified as kaempferol (FEQ-3), 5,4\u2032-dihydroxy-3,7,3\u2032-trimethoxyflavone (FEQ-2), gallic acid (FEQ-5), (+)-catechin (FEQ-7) and (\u2212)-epicatechin (FEQ-8). FEQ-5 exhibited the strongest antioxidant and enzyme inhibitory activities followed by FEQ-3 and FEQ-4. FEQ-2 also displayed potent free radical scavenging activity with IC50 values of 13.79 \u00b1 2.13 (DPPH) and 4.69 \u00b1 1.25 (ABTS) \u00b5g\/mL, respectively. All other compounds were found active either against free radicals or digestive enzymes.<\/jats:p>","DOI":"10.3390\/molecules24061006","type":"journal-article","created":{"date-parts":[[2019,3,14]],"date-time":"2019-03-14T04:15:29Z","timestamp":1552536929000},"page":"1006","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Evaluation of the Enzyme Inhibitory and Antioxidant Activities of Entada spiralis Stem Bark and Isolation of the Active Constituents"],"prefix":"10.3390","volume":"24","author":[{"given":"Fatimah Opeyemi","family":"Roheem","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Chemistry, International Islamic University Malaysia, Bandar Indera Mahkota, 25200 Kuantan, Pahang D.M., Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2769-0120","authenticated-orcid":false,"given":"Siti Zaiton","family":"Mat Soad","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, International Islamic University Malaysia, Bandar Indera Mahkota, 25200 Kuantan, Pahang D.M., Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0565-3222","authenticated-orcid":false,"given":"Qamar Uddin","family":"Ahmed","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, International Islamic University Malaysia, Bandar Indera Mahkota, 25200 Kuantan, Pahang D.M., Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8142-5013","authenticated-orcid":false,"given":"Syed Adnan","family":"Ali Shah","sequence":"additional","affiliation":[{"name":"Atta-ur-Rahman Institute for Natural Products Discovery (AuRIns), Universiti Teknologi MARA, Bandar Puncak Alam, 42300 Selangor Darul Ehsan, Malaysia"},{"name":"Faculty of Pharmacy, Universiti Teknologi MARA, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor D.E., Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jalifah","family":"Latip","sequence":"additional","affiliation":[{"name":"School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bandar Baru Bangi, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5525-7821","authenticated-orcid":false,"given":"Zainul Amiruddin","family":"Zakaria","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia"},{"name":"Halal Institute Research Institute, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,3,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"323","DOI":"10.1016\/S1043-6618(02)00322-5","article-title":"Anti-diabetic effects of Gymnema yunnanense extract","volume":"47","author":"Xie","year":"2003","journal-title":"Pharmacol. 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