油茶籽粕蛋白功能特性及其酶解产物抗氧化活性研究

摘要

采用碱溶酸沉法提取油荼籽粕中的蛋白质,运用正交试验优化提取的最佳条件,并分析油茶籽粕蛋白功能特性及其木瓜蛋白酶水解物的抗氧化活性.结果表明,在pH 10、料液比1∶30 (m/V)、提取时间3h、提取温度50 ℃的最佳条件下,油茶籽粕蛋白的得率为4.99％.油茶籽粕蛋白等电点在pH 5左右.乳化能力、乳化稳定性和起泡能力随pH增加呈先降后升的趋势,与蛋白溶解度密切相关.木瓜蛋白酶能有效提高油茶籽粕蛋白溶解性,其蛋白水解物对DPPH·自由基和羟基自由基均具有很好的清除能力(清除率＞85％),对铜离子的螯合能力大于对铁离子的螯合能力.%The extraction of protein from Camellia oleifera seed-cake by alkali-soluble acid precipitation was used in order to optimize extraction conditions of C.oleifera seed-cake protein (SCP) by orthogonal experimental design.Meanwhile,the functional properties of SCP and antioxidant activity of its hydrolysate prepared by papain were evaluated.Results showed that the optimum extraction conditions were pH 10,material-liquid ratio 1∶30 (m/V),temperature 50 ℃ and time 3 h,based on which SCP yield was 4.99％.SCP isoelectric point was at around pH 5.As pH increased,emulsifying capacity and stability and foaming capacity of SCP presented an initial drop and subsequent rise,positively correlating with protein solubility.Papain treatment improved the protein solubility effectively.Papain-treated hydrolysate possessed excellent DPPH and hydroxyl radical scavenging activity both with above 85％,and copper chelating capacity was stronger than iron chelating capacity.