{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,10]],"date-time":"2026-09-10T16:53:36Z","timestamp":1789059216801,"version":"build-2803163510"},"reference-count":54,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,5,14]],"date-time":"2021-05-14T00:00:00Z","timestamp":1620950400000},"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 and its hydrolysates exhibit a variety of biological characteristics, which include antihypertensive and antioxidant properties. In this study, fish gelatins were extracted from extrusion-pretreated tilapia scales, and then subjected to analyses to determine the physicochemical properties and antioxidant activity of the extracted gelatins. Our findings indicate that TSG2 (preconditioned with 1.26% citric acid) possessed the greatest extraction yield, as well as higher antioxidant activities compared with the other extracted gelatins. Hence, TSG2 was subjected to further hydrolyzation using different proteases and ultrafiltration conditions, which yielded four gelatin hydrolysates: TSGH1, TSGH2, TSGH3, and TSGH4. The results showed that TSGH4 (Pepsin + Pancreatin and ultrafiltration &lt; 3000 Da) had a higher yield and greater antioxidant activity in comparison with the other gelatin hydrolysates. As such, TSGH4 was subjected to further fractionation using a Superdex peptide column and two-stage reverse-phase column HPLC chromatography, yielding a subfraction TSGH4-6-2-b, which possessed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity compared with the other fractions. Further LC-ESI\/MS\/MS analysis of TSGH4-6-2-b suggested two novel peptides (GYDEY and EPGKSGEQGAPGEAGAP), which could have potential as naturally-occurring peptides with antioxidant properties. These promising results suggest that these antioxidant peptides could have applications in food products, nutraceuticals, and cosmetics.<\/jats:p>","DOI":"10.3390\/md19050275","type":"journal-article","created":{"date-parts":[[2021,5,14]],"date-time":"2021-05-14T10:54:22Z","timestamp":1620989662000},"page":"275","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":48,"title":["Physicochemical and Antioxidant Properties of Gelatin and Gelatin Hydrolysates Obtained from Extrusion-Pretreated Fish (Oreochromis sp.) Scales"],"prefix":"10.3390","volume":"19","author":[{"given":"Wei-Cheng","family":"Shiao","sequence":"first","affiliation":[{"name":"Division of Gastroenterology (General Medicine), Department of Internal Medicine, Yuan\u2019s General Hospital, No.162, Cheng Kung 1st Rd., Lingya District, Kaohsiung 80249, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tien-Chiu","family":"Wu","sequence":"additional","affiliation":[{"name":"Division of Hematology and Oncology, Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80756, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3445-5663","authenticated-orcid":false,"given":"Chia-Hung","family":"Kuo","sequence":"additional","affiliation":[{"name":"Department of Seafood Science, National Kaohsiung University of Science and Technology, No. 142, Haijhuan Rd., Nanzih District, Kaohsiung 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 81157, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mei-Ling","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Seafood Science, National Kaohsiung University of Science and Technology, No. 142, Haijhuan Rd., Nanzih District, Kaohsiung 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 82445, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9117-1013","authenticated-orcid":false,"given":"Chun-Yung","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Seafood Science, National Kaohsiung University of Science and Technology, No. 142, Haijhuan Rd., Nanzih District, Kaohsiung 81157, Taiwan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1016\/j.tifs.2019.05.010","article-title":"1-Deoxynojirimycin, its potential for management of non-communicable metabolic diseases","volume":"89","author":"Thakur","year":"2019","journal-title":"Trends Food Sci. Technol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3341","DOI":"10.1021\/acs.jafc.9b00324","article-title":"Licochalcone B extracted from Glycyrrhiza uralensis fisch induces apoptotic effects in human hepatoma cell HepG2","volume":"67","author":"Wang","year":"2019","journal-title":"J. Agric. Food Chem."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/S0899-9007(00)00570-0","article-title":"Reactive oxygen species in human health and disease","volume":"17","author":"Castro","year":"2001","journal-title":"Nutrition"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1007\/s11746-998-0032-9","article-title":"Free radicals, oxidative stress, and antioxidants in human health and disease","volume":"75","author":"Aruoma","year":"1998","journal-title":"J. Am. Oil Chem. Soc."},{"key":"ref_5","first-page":"343","article-title":"Carcinogenicity of butylated hydroxyanisole in F344 rats","volume":"70","author":"Ito","year":"1983","journal-title":"J. Natl. Cancer Inst."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Huang, C.Y., Kuo, C.H., and Lee, C.H. (2018). Antibacterial and antioxidant capacities and attenuation of lipid accumulation in 3T3-L1 adipocytes by low-molecular-weight fucoidans prepared from compressional-puffing-pretreated Sargassum crassifolium. Mar. Drugs, 16.","DOI":"10.3390\/md16010024"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Yang, W.N., Chen, P.W., and Huang, C.Y. (2017). Compositional characteristics and in vitro evaluations of antioxidant and neuroprotective properties of crude extracts of fucoidan prepared from compressional puffing-pretreated Sargassum crassifolium. Mar. Drugs, 15.","DOI":"10.3390\/md15060183"},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Huang, C.Y., Tsai, Y.H., Hong, Y.H., Hsieh, S.L., and Huang, R.H. (2018). Characterization and antioxidant and angiotensin I-converting enzyme (ACE)-inhibitory activities of gelatin hydrolysates prepared from extrusion-pretreated milkfish (Chanos chanos) scale. Mar. Drugs, 16.","DOI":"10.3390\/md16100346"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1025387","DOI":"10.1155\/2018\/1025387","article-title":"Free radical-scavenging, anti-inflammatory, and antibacterial activities of water and ethanol extracts prepared from compressional-puffing pretreated mango (Mangifera indica L.) peels","volume":"2018","author":"Huang","year":"2018","journal-title":"J. Food Qual."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1016\/j.foodchem.2019.05.054","article-title":"Vacuum impregnation of fish gelatin combined with grape seed extract inhibits protein oxidation and degradation of chilled tilapia fillets","volume":"294","author":"Zhao","year":"2019","journal-title":"Food Chem."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"527","DOI":"10.1146\/annurev-food-031414-111800","article-title":"Collagen and gelatin","volume":"6","author":"Liu","year":"2015","journal-title":"Annu. Rev. Food Sci. Technol."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Al-Nimry, S., Dayah, A.A., Hasan, I., and Daghmash, R. (2021). Cosmetic, biomedical and pharmaceutical applications of fish gelatin\/hydrolysates. Mar. Drugs, 19.","DOI":"10.3390\/md19030145"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1016\/j.foodchem.2019.05.156","article-title":"Modification of gelatin hydrolysates from grass carp (Ctenopharyngodon idellus) scales by Maillard reaction: Antioxidant activity and volatile compounds","volume":"295","author":"Chen","year":"2019","journal-title":"Food Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1984","DOI":"10.1021\/jf000494j","article-title":"Isolation and characterization of antioxidative peptides from gelatin hydrolysate of Alaska pollack skin","volume":"49","author":"Kim","year":"2001","journal-title":"J. Agric. Food Chem."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1080\/10408399009527513","article-title":"Chemical and nutritional changes in foods during extrusion","volume":"29","author":"Camire","year":"1990","journal-title":"Crit. Rev. Food Sci. Nutr."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"10451","DOI":"10.1016\/j.biortech.2011.08.118","article-title":"Pretreatment of rice straw using an extrusion\/extraction process at bench-scale for producing cellulosic ethanol","volume":"102","author":"Chen","year":"2011","journal-title":"Bioresour. Technol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"884","DOI":"10.1016\/j.foodchem.2012.12.003","article-title":"Effects of twin-screw extrusion on soluble dietary fibre and physicochemical properties of soybean residue","volume":"138","author":"Jing","year":"2013","journal-title":"Food Chem."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"997","DOI":"10.1016\/j.foodchem.2015.06.066","article-title":"Isolation and characterization of fish scale collagen from tilapia (Oreochromis sp.) by a novel extrusion\u2013hydro-extraction process","volume":"190","author":"Huang","year":"2016","journal-title":"Food Chem."},{"key":"ref_19","unstructured":"Fisheries Agency, Council of Agriculture, Executive Yuan, Taiwan (2021, April 21). Fisheries Statistical Yearbook, Available online: https:\/\/www.fa.gov.tw\/cht\/PublicationsFishYear\/."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1016\/S0141-8130(03)00054-0","article-title":"Physical properties of type I collagen extracted from fish scales of Pagrus major and Oreochromis niloticas","volume":"32","author":"Ikoma","year":"2003","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"581","DOI":"10.1016\/j.foodhyd.2003.08.009","article-title":"Extraction and physico-chemical characterisation of Nile perch (Lates niloticus) skin and bone gelatin","volume":"18","author":"Muyonga","year":"2004","journal-title":"Food Hydrocoll."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1016\/j.biortech.2005.11.021","article-title":"Extraction and characterisation of gelatine from Atlantic salmon (Salmo salar) skin","volume":"98","author":"Arnesen","year":"2007","journal-title":"Bioresour. Technol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"161","DOI":"10.1016\/j.lwt.2009.06.012","article-title":"Chemical compositions and characterisation of skin gelatin from farmed giant catfish (Pangasianodon gigas)","volume":"43","author":"Jongjareonrak","year":"2010","journal-title":"LWT Food Sci. Technol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1216","DOI":"10.1016\/j.foodhyd.2006.01.006","article-title":"Skin gelatin from bigeye snapper and brownstripe red snapper: Chemical compositions and effect of microbial transglutaminase on gel properties","volume":"20","author":"Jongjareonrak","year":"2006","journal-title":"Food Hydrocoll."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1016\/j.foodchem.2006.01.046","article-title":"Preparation and characterisation of gelatins from the skins of sin croaker (Johnius dussumieri) and shortfin scad (Decapterus macrosoma)","volume":"101","author":"Cheow","year":"2007","journal-title":"Food Chem."},{"key":"ref_26","unstructured":"Sperling, L.H. (1985). Introduction to Physical Polymer Science, Wiley."},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Harris, P. (1990). Gelatine. Food Gels, Elsevier Applied Science.","DOI":"10.1007\/978-94-009-0755-3"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"825","DOI":"10.1016\/j.lwt.2008.11.014","article-title":"Processing optimization and characterization of gelatin from lizardfish (Saurida spp.) scales","volume":"42","author":"Wangtueai","year":"2009","journal-title":"LWT Food Sci. Technol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1441","DOI":"10.1016\/j.foodchem.2012.02.032","article-title":"Extraction and characterisation of pepsin-solubilised collagen from fins, scales, skins, bones and swim bladders of bighead carp (Hypophthalmichthys nobilis)","volume":"133","author":"Liu","year":"2012","journal-title":"Food Chem."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"32","DOI":"10.1016\/j.ijbiomac.2012.10.026","article-title":"Effect of fish collagen modification on its thermal and rheological properties","volume":"53","author":"Safandowska","year":"2013","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1016\/j.foodhyd.2009.09.001","article-title":"Comparative study on characteristics of gelatin from the skins of brownbanded bamboo shark and blacktip shark as affected by extraction conditions","volume":"24","author":"Kittiphattanabawon","year":"2010","journal-title":"Food Hydrocoll."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1016\/j.foodchem.2003.06.006","article-title":"Characterisation of acid soluble collagen from skins of young and adult Nile perch (Lates niloticus)","volume":"85","author":"Muyonga","year":"2004","journal-title":"Food Chem."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1016\/j.foodchem.2003.09.038","article-title":"Fourier transform infrared (FTIR) spectroscopic study of acid soluble collagen and gelatin from skins and bones of young and adult Nile perch (Lates niloticus)","volume":"86","author":"Muyonga","year":"2004","journal-title":"Food Chem."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1120","DOI":"10.1080\/10498850.2018.1535530","article-title":"Thermal and chemical properties of gelatin from tilapia (Oreochromis niloticus) scale","volume":"27","author":"Martins","year":"2018","journal-title":"J. Aquat. Food Prod. Technol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"4163","DOI":"10.1016\/j.matpr.2016.11.091","article-title":"A facile solid state synthesis of cone-like ZnO microstructure an efficient solar-light driven photocatalyst for rhodamine B degradation","volume":"3","author":"Rokesh","year":"2016","journal-title":"Mater. Today Proc."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1016\/j.jff.2015.04.042","article-title":"Purification and characterization of three antioxidant peptides from protein hydrolysate of grass carp (Ctenopharyngodon idella) skin","volume":"16","author":"Cai","year":"2015","journal-title":"J. Funct. Foods"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"69","DOI":"10.1016\/S0308-8146(01)00251-5","article-title":"An investigation of antioxidant capacity of fruits in Singapore markets","volume":"76","author":"Leong","year":"2002","journal-title":"Food Chem."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1177\/1082013206062422","article-title":"Antioxidant potential of Ecklonia cavaon reactive oxygen species scavenging, metal chelating, reducing power and lipid peroxidation inhibition","volume":"12","author":"Senevirathne","year":"2006","journal-title":"Food Sci. Technol. Int."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1297","DOI":"10.2174\/1381612033454892","article-title":"Food-derived bioactive peptides-opportunities for designing future foods","volume":"9","author":"Korhonen","year":"2003","journal-title":"Curr. Pharm. Des."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"6","DOI":"10.1016\/j.ijbiomac.2009.10.015","article-title":"Potential antioxidant and anticoagulant capacity of low molecular weight fucoidan fractions extracted from Laminaria japonica","volume":"46","author":"Wang","year":"2010","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"499","DOI":"10.1007\/BF02327894","article-title":"Study of the efficiency of a mobile phase used in size-exclusion HPLC for the separation of peptides from a casein hydrolysate according to their hydrodynamic volume","volume":"32","author":"Lemieux","year":"1991","journal-title":"Chromatographia"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1016\/j.foodres.2012.12.031","article-title":"Influence of average molecular weight on antioxidant and functional properties of cartilage collagen hydrolysates from Sphyrna lewini, Dasyatis akjei and Raja porosa","volume":"51","author":"Li","year":"2013","journal-title":"Food Res. Int."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1939","DOI":"10.4315\/0362-028X-67.9.1914","article-title":"Antioxidant activity of peptides derived from egg white proteins by enzymatic hydrolysis","volume":"67","author":"Miguel","year":"2004","journal-title":"J. Food Prot."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1016\/j.foodchem.2010.02.013","article-title":"Purification of antioxidative peptides prepared from enzymatic hydrolysates of tuna dark muscle by-product","volume":"122","author":"Hsu","year":"2010","journal-title":"Food Chem."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"384","DOI":"10.1016\/j.jff.2013.11.005","article-title":"Structural and functional characterization of hemp seed (Cannabis sativa L.) protein-derived antioxidant and antihypertensive peptides","volume":"6","author":"Girgih","year":"2014","journal-title":"J. Funct. Foods"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1016\/j.idairyj.2014.03.015","article-title":"Antioxidant peptides from goat milk protein fractions hydrolysed by two commercial proteases","volume":"39","author":"Skibsted","year":"2014","journal-title":"Int. Dairy J."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1016\/S0308-8146(99)00188-0","article-title":"Isolation of collagen from fish waste material\u2014Skin, bone and fins","volume":"68","author":"Nagai","year":"2000","journal-title":"Food Chem."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"265","DOI":"10.1016\/S0021-9258(19)52451-6","article-title":"Protein measurement with the Folin phenol reagent","volume":"193","author":"Lowry","year":"1951","journal-title":"J. Biol. Chem."},{"key":"ref_49","unstructured":"AOAC (1984). Methods of Analysis, Association of Official Analytical Chemists. [14th ed.]."},{"key":"ref_50","unstructured":"BSI (1975). Methods for Sampling and Testing Gelatin (Physical and Chemical Methods), BSI (British Standards Institution)."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"247","DOI":"10.1016\/j.ijbiomac.2007.11.005","article-title":"Extraction and electrospinning of gelatin from fish skin","volume":"42","author":"Songchotikunpan","year":"2008","journal-title":"Int. J. Biol. Macromol."},{"key":"ref_52","doi-asserted-by":"crossref","unstructured":"Huang, C.Y., Kuo, C.H., and Chen, P.W. (2018). Compressional-puffing pretreatment enhances neuroprotective effects of fucoidans from the brown seaweed Sargassum hemiphyllum on 6-hydroxydopamine-induced apoptosis in SH-SY5Y cells. Molecules, 23.","DOI":"10.3390\/molecules23010078"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"1121","DOI":"10.1016\/j.foodchem.2015.11.100","article-title":"Antioxidant activities of crude extracts of fucoidan extracted from Sargassum glaucescens by a compressional-puffing-hydrothermal extraction process","volume":"197","author":"Huang","year":"2016","journal-title":"Food Chem."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"766","DOI":"10.1016\/j.jfda.2015.07.002","article-title":"Antioxidant activity and growth inhibition of human colon cancer cells by crude and purified fucoidan preparations extracted from Sargassum cristaefolium","volume":"23","author":"Wang","year":"2015","journal-title":"J. Food Drug Anal."}],"container-title":["Marine Drugs"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1660-3397\/19\/5\/275\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:00:47Z","timestamp":1760162447000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1660-3397\/19\/5\/275"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,5,14]]},"references-count":54,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2021,5]]}},"alternative-id":["md19050275"],"URL":"https:\/\/doi.org\/10.3390\/md19050275","relation":{},"ISSN":["1660-3397"],"issn-type":[{"value":"1660-3397","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,5,14]]}}}