猴头菌液体发酵产α-半乳糖苷酶工艺优化及其酶学性质

Process Optimization for α-galactosidase Produced by Liquid Fermentation of Hericium erinaceus and Its Enzymatic Properties

为优化猴头菌(Hericium erinaceus)液体发酵产α-半乳糖苷酶的培养条件,研究其酶学性质。采用单因素实验和Box-Behnken设计原理设计实验,建立以酶活性为响应值的回归方程模型,采用Design-Expert得到最优液体发酵产酶工艺,采用硫酸铵沉淀初步纯化该酶,研究该酶的温度、pH特性及其对蛋白酶的抗性。结果表明:猴头菌发酵产酶的最佳发酵工艺为3%豆粕粉、2.3%葡萄糖、1.9%蛋白胨、0.3%MgCl2,在此条件下猴头菌发酵液中的α-半乳糖苷酶活性提高了48.9%;该酶最适反应温度为60℃,最适pH为6.0,对胃蛋白酶、胰蛋白酶、酸性蛋白酶和中性蛋白酶均表现出较好的抗性。

Single factor experiment and Box-Behnken design principle were used to optimizeα-galactosidase production by liquid fermentation of Hericium erinaceus.Using enzyme activity as the response value,a regression equation model was established.The optimal liquid fermentation enzyme production condition was obtained by Design-Expert.The enzyme was preliminarily purified by ammonium sulfate precipitation,and then studied for its temperature and pH characteristics and resistance to proteases.The results showed that the optimal fermentation medium comprised 3%soybean meal,2.3%glucose,1.9%peptone,and 0.3%MgCl2.Using the optimal medium,α-galactosidase activity increased by 48.9%.This enzyme’s activity was best at 60℃and pH 6.0.This enzyme showed resistance to pepsin,trypsin,acid protease and neutral protease.