秸秆纤维素分解菌的选育及发酵工艺研究

On Selective Breeding and Fermenting Technology of Straw Cellulose Decomposing Fungus

对筛选出的一株纤维素酶高产菌株———青霉菌的产酶条件和酶活性进行了研究。结果表明,该青霉菌以秸秆∶麦麸之比3∶1为碳源,硫酸铵和蛋白胨混合为氮源时,有利于酶的分泌和纤维素的分解。该纤维素酶的最适酶解pH值为6,温度为30℃;Na+对纤维素酶具有激活作用,Cu2+则明显抑制纤维素酶的活性;VB2可以提高纤维素的分解率,VC使酶活力和纤维素的分解率明显升高。将该菌株分别与酿酒酵母和里氏木霉混合培养后,酶活力和纤维素的分解率均大幅度提高。

The enzyme production condition and enzyme activity of a high-yield fungus of cellulase selected through experimentpenicillium were studied. The result showed that the penicillium was helpful for secretion of enzyme and decomposition of cellulose, when taking straw and bran when a proportion of 3：1 as carbon source, and mixture of ammonia sulfate and peptone as carbon source. The best enzymolysis pH of cellulase was 6 and the enzymolysis temperature was 3022. Na^＋ could activate eellulase, while Cu^2＋ could inhibit activity of cellulase obviously. VB2 could improve the decomposition rate of cellulase, while it was possible to improve the decomposition rate of enzyme activity and cellulase distinctly by adding VC. In addition, the decomposition of cellulase material needed combined action of many microorganisms ; the decomposition rate of enzyme activity and cellulase would be improved substantially after mixing and culturing the strain with distillers yeast and Trichoderma reesei separately.