白腐真菌产木质素降解酶的条件及酶学性质的研究

Studies on Production Conditions and Properties of Ligninolytic Enzymes from White Rot Fungi

本研究以酶活力为评价指标,通过产酶条件的优化,选择出白腐真菌的最适培养条件,并对其部分酶作用特性进行了研究。试验结果表明:白腐真菌产锰过氧化物酶的最适培养条件是:最佳碳源是麸皮,葡萄糖(碳源)对酶活力影响不大;最佳氮源是牛肉膏;最佳培养时间是96 h。该菌产漆酶的最适培养条件是:最佳碳源是麸皮;最佳氮源是牛肉膏;最佳培养时间是96 h。锰过氧化物酶的最适pH范围是4.4～4.8,最适底物浓度是1.2 mmol/L,最适反应温度是35～40℃;漆酶的最适pH为4.8,最适底物浓度是1.2 mmol/L,最适反应温度是40℃。金属离子Cu2+,Co2+对锰过氧化物酶和漆酶有激活作用,Fe2+对两种酶活力有一定的抑制作用,而Ag+则完全抑制漆酶的活性,Mg2+对两种酶活力影响不大。

Taking enzyme vitality as evaluation criterion, the culture conditions of white rot optimized and parts of function character of enzyme were studied. The results showed that the optimal for White rot fungi to has not distinct effect produce manganese peroxidase was as follows： Bran was to enzyme vitality; beef cream was the optimal source fungi were conditions the best source of carbon, glucose of nitrogen; and the best time to culture was 96 hours. The optimal conditions for white rot fungi to produce laccase were as similar as that of manganese peroxidase. The optimal pH range for manganese peroxidase was 4.4-4.8, the optimal concentrations of substrates was 1.2 mmol/L, the optimal temperature for reaction was 35℃. The optimal pH for Laccase was 4.8, the optimal concentrations of substrates was 1.2 mmol/L, the optimal temperature for reaction was 40℃. Cu^2＋ and Co^2＋. have activation to manganese peroxidase and Laccase, Fe^2＋ has some inhibition to them. However, Ag^＋ completely inhibit the vitality of Laccase. Mg^2＋ has little effect to the vitality of two enzymes.