Dang Meizhu, Wang Ruifeng, Jia Yangyang, Du Jing, Wang Ping, Xu Yawei, Li Chunmei
College of Food Science and Technology, Huazhong Agricultural University, Wuhan 430072, China.
School of Energy and Intelligence Engineering, Henan University of Animal Husbandry and Economy, Zhengzhou 450002, China.
Foods. 2022 Jun 22;11(13):1830. doi: 10.3390/foods11131830.
The purpose of this study is to obtain new antifreeze peptides (AFPs) that are natural, safe, and high activity from scales. The optimal hydrolysis conditions were investigated, and chromatography-based isolation was conducted using thermal hysteresis activity (THA) as an index. Molecular dynamic simulation (MDs) was explored to reveal the antifreeze mechanism of the AFPs. The results showed that the optimal hydrolysis conditions were 4000 U/g papain enzyme for 60 °C at pH 5.0 and substrate concentration (1:10) for 3 h, as unveiled by single-factor experiment results. The AFPs documented a THA of 2.7 °C when the T was 1.3 °C. Hydrophilic peptide, named GCFSC-AFPs, with a THA of 5.09 °C when the T was 1.1 °C was obtained after a series isolation of gel filtration, ion exchange, and reversed-phase HPLC chromatography. The AFPs had a molecular weight of 1107.54~1554.72 Da with three main peptides in the amino acid sequence of VGPAGPSGPSGPQ, RGSPGERGESGPAGPSG, and VGPAGPSGPSGPQG, respectively. The survival rate of yeast with GCFSC-AFPs reached 84.4% following one week of exposure at -20 °C. MDs indicated that GCFSC-AFPs interfered with the ice-water interaction and thus inhibited the ice crystallization process. Our data suggested that the GCFSC-AFPs were a novel and potential antifreeze agent in the food industry.
本研究的目的是从鱼鳞中获得天然、安全且具有高活性的新型抗冻肽（AFPs）。研究了最佳水解条件，并以热滞活性（THA）为指标进行基于色谱的分离。探索了分子动力学模拟（MDs）以揭示AFPs的抗冻机制。结果表明，单因素实验结果显示，最佳水解条件为在pH 5.0、60℃下使用4000 U/g木瓜蛋白酶3小时，底物浓度为（1:10）。当温度为1.3℃时，AFPs的热滞活性为2.7℃。经过凝胶过滤、离子交换和反相高效液相色谱的一系列分离后，获得了一种亲水性肽，命名为GCFSC-AFPs，当温度为1.1℃时，其热滞活性为5.09℃。AFPs的分子量为1107.54~1554.72 Da，在氨基酸序列中分别有三个主要肽段，即VGPAGPSGPSGPQ、RGSPGERGESGPAGPSG和VGPAGPSGPSGPQG。在-20℃下暴露一周后，含有GCFSC-AFPs的酵母存活率达到84.4%。分子动力学模拟表明，GCFSC-AFPs干扰了冰水相互作用，从而抑制了冰晶形成过程。我们的数据表明，GCFSC-AFPs是食品工业中一种新型且具有潜力的抗冻剂。
