耐高温产酯酶芽孢菌的筛选及产酯酶条件与酶学特性研究
关键词：耐高温芽孢菌；酯化酶；筛选；发酵条件；作用特性
Selection of a Strain of Thermostable Esterase Producing Bacillus and Study on Production Conditions and Enzymatic Properties of Lipase
Abstract: Taking the Bacillus that preserved frozen in laboratory fermented strain, cultured under 55℃condition after the activation, the high temperature resistant bacillus which produced esterase was screened, by the method of observing the transparent circle and liquid fermentation, the esterase activity was selected for the determination of index, with screening strains as test strains, the esterase producing conditions and the esterase action features of high temperature resistant bacillus were studied with the method of orthogonal test and single factor experiment, the results showed that: the number of SPM2-2 high temperature resistant bacillus was the best esterase producing Bacillus under 55℃ culture condition, the producing esterase activity reached 14 μmol/min. The best carbon source of high temperature resistant bacillus SPM2-2 for esterase producing fermentation was starch, yeast extract was the best nitrogen source, the time 24 h was the best optimum fermentation, the best metal ion was Ca2+, the most suitable esterifying enzyme effect of pH value reached 7, 40℃was the best optimum temperature. When pH value was 7, the temperature was 30℃, and the fermentation time was 36 h, the esterification enzyme activity was the highest, the ability of esterase producing could reach 22.13 μ mol/min.
Key words: High temperature resistant bacillus; Esterifying enzyme; Screening; Fermentation condition; Function characteristics
目 录
摘 要 1
Abstract 1
引言 2
1. 材料与方法 2
1.1 实验材料 2
1.1.1 实验试材 2
1.1.2 主要培养基 2
1.1.3 试剂 3
1.2 主要仪器与设备 3
1.3 主要实验方法 3
1.3.1 耐高温产酯酶芽孢菌的活化 4
1.3.2 耐高温产酯酶芽孢菌的初筛 4
1.3.3 耐高温产酯酶芽孢菌的复筛 4
1.3.4 耐高温芽孢菌产酯酶发酵条件试验 4
1.3.4.1 碳源的选择 4
1.3.4.2 氮源的选择 4
1.3.4.3发酵时间的选择 4
1.3.4.4 金属离子的选择 4
1.3.5 耐高温芽孢菌产酯酶酶学特性试验 5
1.3.5.1 酯酶作用最适pH值的影响 5
1.3.5.2 酯酶最适作用温度 5
1.3.6 耐高温芽孢菌酯化酶作用条件的正交优化试验 5
1.3.7 酯化酶活力的测定 5
2. 结果与分析 6
2.1 耐高温产酯酶芽孢菌的筛选 6
2.1.1 耐高温产酯酶芽孢菌的初筛 6
2.1.2 耐高温产酯酶芽孢菌的复筛 7