In this paper, a new type of antifreeze peptide was identified from the ultrasonic-assisted enzymolysis product of yak skin. First, the antifreeze peptides were obtained by ultrasonic-assisted enzymolysis of yak skin gelatin. The obtained peptides with 150 W ultrasound treatment could increase the survival rate of Lactobacillus plantarum from 16 % to 60 % after four freeze–thaw cycles. Then, the component with the highest antifreeze activity in the peptides’ ultrafiltration product was analyzed by LC-MS/MS to obtain 961 peptides. After screening of antifreeze activity and physical properties, three antifreeze peptide sequences were obtained (S1: GERGGPGGPGPQ, S2: PGGAEGPGRDAQQP, S3: VAPPGAPKKEH). DSC analysis, Lactobacillus plantarum cryoprotection experiments and molecular docking showed that the S1 sequence had the best antifreeze activity. This study provides a new idea for the high-value utilization of yak by-products and a potential candidate for food antifreeze agents.

中文翻译：

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从牦牛皮明胶超声辅助酶解物中鉴定新型防冻肽


本文从牦牛皮肤的超声辅助酶解产物中鉴定出一种新型的防冻肽。首先，通过超声辅助酶解牦牛皮明胶获得防冻肽。经 150 W 超声处理获得的肽可在 4 次冻融循环后将植物乳杆菌的存活率从 16 % 提高到 60 %。然后，通过 LC-MS/MS 分析肽超滤产物中防冻活性最高的组分，得到 961 个肽。经过防冻活性和物理性质筛选，得到 3 个防冻肽序列 （S1： GERGGPGGPGPQ， S2： PGGAEGPGRDAQQP， S3： VAPPGAPKKEH）。DSC 分析、植物乳杆菌低温保护实验和分子对接表明，S1 序列具有最好的防冻活性。本研究为牦牛副产品的高值化利用提供了新思路，是食品防冻剂的潜在候选者。