{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,21]],"date-time":"2026-07-21T04:54:49Z","timestamp":1784609689544,"version":"3.55.0"},"reference-count":56,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2018,9,22]],"date-time":"2018-09-22T00:00:00Z","timestamp":1537574400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>Fish gelatin hydrolysates have been shown to possess various biological activities due to their unique Gly-Pro-Y and Gly-X-Hyp sequences. In the current study, fish gelatin was extracted from non-extruded milkfish scale (FSG1) or extrusion-pretreated milkfish scale (FSG2); extracted gelatins were hydrolyzed with different combinations of Flavourzyme and Alcalase to give four different hydrolysates, namely: FSGH1 (FSG1 hydrolyzed with Flavourzyme), FSGH2 (FSG1 hydrolyzed with Alcalase + Flavourzyme), FSGH3 (FSG2 hydrolyzed with Flavourzyme), and FSGH4 (FSG2 hydrolyzed with Alcalase + Flavourzyme). The extrusion-pretreatment process enhanced the extraction yield of gelatin from fish scale. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared (FTIR) analyses showed the extracts FSG1 and FSG2 possessed characteristics of gelatin. Moreover, the physicochemical characteristics of FSGH1\u2013FSGH4 were examined by analyses of their degree of hydrolysis, amino acid composition, UV spectrum, FTIR spectrum, molecular weight, and RP-HPLC profile. Additional biological functional analyses showed that all of the studied gelatin hydrolysates FSGH1\u2013FSGH4 possessed antioxidant activity dose-dependently as revealed by DPPH scavenging, ABTS scavenging, and reducing power analyses. In addition, FSGH2 and FSGH4 showed higher angiotensin-I-converting enzyme (ACE)-inhibitory activity as compared to FSGH1 and FSGH3. Taken together, FSGH2 and FSGH4 showed high antioxidant activity and potent anti-ACE activity. Due to the potential antioxidant and antihypertensive properties of FSGH2 and FSGH4, further research is needed to explore their possible use as natural supplementary raw materials in food and nutraceutical products.<\/jats:p>","DOI":"10.3390\/md16100346","type":"journal-article","created":{"date-parts":[[2018,9,24]],"date-time":"2018-09-24T10:38:49Z","timestamp":1537785529000},"page":"346","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":35,"title":["Characterization and Antioxidant and Angiotensin I-Converting Enzyme (ACE)-Inhibitory Activities of Gelatin Hydrolysates Prepared from Extrusion-Pretreated Milkfish (Chanos chanos) Scale"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9117-1013","authenticated-orcid":false,"given":"Chun-Yung","family":"Huang","sequence":"first","affiliation":[{"name":"Department of Seafood Science, National Kaohsiung University of Science and Technology, No. 142, Haijhuan Rd., Nanzih District, Kaohsiung City 81157, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yung-Hsiang","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Seafood Science, National Kaohsiung University of Science and Technology, No. 142, Haijhuan Rd., Nanzih District, Kaohsiung City 81157, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yong-Han","family":"Hong","sequence":"additional","affiliation":[{"name":"Department of Nutrition, I-Shou University (Yanchao Campus), No. 8, Yida Rd., Jiaosu Village, Yanchao District, Kaohsiung City 82445, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shu-Ling","family":"Hsieh","sequence":"additional","affiliation":[{"name":"Department of Seafood Science, National Kaohsiung University of Science and Technology, No. 142, Haijhuan Rd., Nanzih District, Kaohsiung City 81157, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ren-Han","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Nursing, Mackay Medical College, No.46, Sec. 3, Zhongzheng Rd., Sanzhi District, New Taipei City 25245, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,9,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"424","DOI":"10.1016\/j.mad.2006.01.021","article-title":"Biphasic effects of dietary antioxidants on oxidative stress-mediated carcinogenesis","volume":"127","author":"Lee","year":"2006","journal-title":"Mech. 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