白果活性蛋白的酶法水解及抗氧化活性研究

Enzymic hydrolysis of ginkgo albumin protein and itsantioxidant activity

白果活性蛋白(GAP)是华中农业大学天然产物化学实验室首次从白果中分离得到的一种以清蛋白为主的且具有显著生物活性的蛋白,为扩大该蛋白在食品中的用途,提高其生物活性,研究了酶法水解制备白果肽段的方法及其抗氧化活性的变化。通过单因素分析、正交试验以及对试验结果的分析,确定了2709碱性蛋白酶水解白果活性蛋白的最佳水解条件为:底物浓度1%,pH值8.5,水解温度45℃,酶浓度7000 U/g,反应时间6 h。以F en ton体系和邻苯三酚体系检验其抗氧化活性,结果表明白果肽段较酶解前的活性蛋白,抗氧化活性有不同程度的提高,但两者均具有较强的抗氧化活性。

Ginkgo Albumin Protein （GAP） was separated from Ginkgo seeds for the first time by Natural Products Lab of Huazhong Agricultural University, which exhibited remarkable biological activity in former studies. In order to improve its biological activity and use in food industry, preparation method of ginkgo peptides from GAP by enzymatic hydrolysis and change of antioxidant activity were studied. The optimal conditions for enzymatic hydrolysis were obtained by single factor analysis and then orthogonal experiment： the substrate concentration was 1% and the enzyme concentration is 7000 u per gram of substrate; the hydrolysis process was performed under 45℃, pH 8.5 for 6 h. Scavenging abilities of superoxide radicals and hydroxyl radical of GAP and Ginkgo peptides were evaluated in Fenton system and pyrogallic acid system. The results showed that GAP and Ginkgo peptides both exhibited strong antioxidant activity and the activity of the peptides was higher than GAP＇s at the same concentration.