{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,8]],"date-time":"2026-11-08T03:24:15Z","timestamp":1794108255383,"version":"4.8.0"},"reference-count":45,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,17]],"date-time":"2025-06-17T00:00:00Z","timestamp":1750118400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Science and Technology Smes Innovation Ability Improvement Project of Shandong Province","award":["2023TSGC0386"],"award-info":[{"award-number":["2023TSGC0386"]}]},{"name":"Science and Technology Smes Innovation Ability Improvement Project of Shandong Province","award":["2022TZXD0033"],"award-info":[{"award-number":["2022TZXD0033"]}]},{"name":"Science and Technology Smes Innovation Ability Improvement Project of Shandong Province","award":["SDAIT-07-17"],"award-info":[{"award-number":["SDAIT-07-17"]}]},{"name":"Key R&amp;D Program of Shandong Province","award":["2023TSGC0386"],"award-info":[{"award-number":["2023TSGC0386"]}]},{"name":"Key R&amp;D Program of Shandong Province","award":["2022TZXD0033"],"award-info":[{"award-number":["2022TZXD0033"]}]},{"name":"Key R&amp;D Program of Shandong Province","award":["SDAIT-07-17"],"award-info":[{"award-number":["SDAIT-07-17"]}]},{"name":"Shandong Agricultural Industry Technology System","award":["2023TSGC0386"],"award-info":[{"award-number":["2023TSGC0386"]}]},{"name":"Shandong Agricultural Industry Technology System","award":["2022TZXD0033"],"award-info":[{"award-number":["2022TZXD0033"]}]},{"name":"Shandong Agricultural Industry Technology System","award":["SDAIT-07-17"],"award-info":[{"award-number":["SDAIT-07-17"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Foods"],"abstract":"<jats:p>Iron deficiency is a global health issue, making the development of novel iron supplements to enhance iron absorption critically important. In this study, low molecular weight donkey-hide gelatin peptides (LMW DHGP) were enzymatically hydrolyzed from donkey-hide gelatin. Experimental results demonstrated that the iron chelating capacity of LMW DHGP reached 249.98 \u03bcg\/mg. Key amino acids (Asn, Gly, Cys, Lys) may participate in chelation. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis showed rough, porous amorphous structures of LMW DHGP-iron complexes. The results of circular dichroism spectroscopy (CD) indicated that the self-assembly of LMW DHGP-iron complexes appears to be primarily mediated by peptide \u03b1-helical structural conformations. Fourier transform infrared (FTIR) spectroscopy further indicated that the interaction between LWM DHGP and Fe2+ likely occurs through carboxyl and amino functional groups. In vitro digestion stability studies demonstrated that LMW DHGP-iron complexes exhibited superior iron ion solubility compared to FeSO4 in simulated gastrointestinal conditions. PGPAG-iron complexes exhibited the highest antioxidant activity, with scavenging rates of 71.64% (DPPH radical) and 88.79% (ABTS radical). These findings collectively suggest that LMW DHGP-iron complexes possess significant potential as a novel iron supplement in food applications, which provides valuable theoretical insights for the development of innovative iron supplementation strategies.<\/jats:p>","DOI":"10.3390\/foods14122117","type":"journal-article","created":{"date-parts":[[2025,6,17]],"date-time":"2025-06-17T03:37:07Z","timestamp":1750131427000},"page":"2117","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Donkey-Hide Gelatin Peptide-Iron Complexes: Structural Characterization, Enhanced Iron Solubility Under Simulated Digestion, and Dual Iron Chelation-Antioxidant Functions"],"prefix":"10.3390","volume":"14","author":[{"given":"Lili","family":"Yang","sequence":"first","affiliation":[{"name":"Shandong Key Laboratory of Applied Technology for Protein and Peptide Drugs, School of Pharmaceutical Sciences and Food Engineering, Liaocheng University, Liaocheng 252059, China"},{"name":"College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2957-3614","authenticated-orcid":false,"given":"Chenyan","family":"Lv","sequence":"additional","affiliation":[{"name":"College of Food Science & Nutritional Engineering, China Agricultural University, Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-3811-2646","authenticated-orcid":false,"given":"Xingfeng","family":"Guo","sequence":"additional","affiliation":[{"name":"Shandong Key Laboratory of Applied Technology for Protein and Peptide Drugs, School of Pharmaceutical Sciences and Food Engineering, Liaocheng University, Liaocheng 252059, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rong","family":"Liang","sequence":"additional","affiliation":[{"name":"Shandong Key Laboratory of Applied Technology for Protein and Peptide Drugs, School of Pharmaceutical Sciences and Food Engineering, Liaocheng University, Liaocheng 252059, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1016\/j.tifs.2021.07.005","article-title":"Food-based iron delivery systems: A review","volume":"116","author":"Varidi","year":"2021","journal-title":"Trends Food Sci. 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