黑曲霉固态发酵产糖化酶的研究

Glucoamylase production of Aspergillus niger in solid-state fermentation

以糖化酶活力为评价指标,对1株黑曲霉变异株固态发酵产糖化酶的培养基组成和发酵条件进行了研究,分别考察了碳源、氮源、原料粉碎度、培养基含水量、温度、起始pH值、发酵时间、接种量等对该菌株固态发酵产糖化酶的影响。结果表明,该菌株产糖化酶的最佳发酵培养基组成为:麦麸:豆饼粉=3:1,(NH4)2SO4含量为3%,K2HPO40.1%。原料粉碎度为过60目筛,起始pH5.0,培养基含水量为120%,培养温度为32℃,接种量为每瓶培养基接108/mL的孢子悬液2.5mL,培养时间为72h,最高产酶活力达17800U/g。

Taking glucoamylase activity as assessment standard, the medium of solid-state fermentation and fermentation conditions of an Aspergillus niger mutant were studied. The effects of carbon sources, nitrogen sources, smash degree of raw material, water content of medium, temperature, initial pH, fermentation time and inoculum on glucoamylase production during solid fermentation were investigated respectively. It was shown that the optimal conditions for glucoamylase production by the A. niger mutant were as follows： bran： soybean cake meal=3：1; （NH4）2SO4 3%; K2HPO4 0.1%; the raw materials was granulated through 60-mesh sieve; initial pH 5.0; water content of culture medium 120%; fermentation temperature 32℃; inoculum of spore suspension （10^8/ml） 2.5 ml/bottle; fermentation time 72 h. Under above conditions, the highest glucoamylase activity was detected as 17800 U/g.