黑曲霉9813X_8株的选育及其固态发酵条件的优化研究

STUDIES ON SCREENING OF ASPERGILLUS NIGER 9813X_8AND SOLID-FERMENTATION CONDITIONS

从自然界中分离出的黑曲霉9813株经诱变处理，获得一株高产纤维素酶的9813X8突变株。对9813X8株固态发酵产纤维素酶、半纤维素酶及果胶酶的优化条件进行了研究。通过综合评分的决策方法分析表明，黑曲霉9813X8株的产酶优化条件为：稻草与麸皮的比例1:1，料水比1:2，氮源是1.0% 硫酸铵和1.0% 豆饼，培养基起始pH值3.2～3.5，250 ml三角瓶中装培养基5～10 g，培养时间48～60 h；用0.2 mol/L、pH4.8的醋酸缓冲液室温下浸提3 h，所得粗酶液活性最高。

A mutant strain 9813X8 with high yield of Cellulase was obtained from Aspergillus Niger 9813 which was isolated from nature by treatment of Ultraviolet radiation and N-methyl-N-nitro-N-nitrosoguanidine. Using decision method of the synthetic grade, the results showed that the optimum condition of producing Cellulase, Hemlcellulase and Pectinase were as follows: the proportion of straw powder to wheat bran was 1:1,the water amount of medium was 200%, pH was at 3.2～3.5,the temperature was 30℃ and the time was 60 min, additional nitrogen compounds were 1.0% (NH4)2SO4 and 1.0% bean cake, ventilatory capacity was 5～10 g in 250 ml triangle bottle，in the solid-state medium of straw powder and wheat bran. Enzyme solution was extracted by 0.02 mol/L、pH4.8 acetum at the room temperature for 3 h.