植酸酶产生菌的选育及固态产酶条件研究

植酸酶催化植酸,并将其盐类水解成肌醇和磷酸,因此植酸酶的使用可以提高植酸磷的吸收利用率,降低饲料成本,同时还可保护生态环境.经分离和亚硝基胍诱变选育,得到一株植酸酶高产菌株绿色木霉LH374,并对该菌株固态发酵产植酸酶的条件和扩大生产进行了研究.结果表明,固态发酵的最佳条件:稻草和米糠的比例为8:2,培养基起始pH为6.5,最适温度为30℃,最适培养时间为96 h,含水量为60%,硫酸铵的流加量为2%.绿色木霉LH37在上述最适条件下生产植酸酶平均可达1 580 U·g^-1.

Screening of phytase-producing strain and its optimal solid state phytase-producing conditions

Phytase can catalyze phytate hydrolyzed into inositol and phosphoric acid, and its application could make the phytic acid in animal feeds become more available, decrease feed cost, and at the same time, protect eco-environment. In this paper, a phytase-producing strain Trichoderma Viride LH374 was obtained through isolation and mutation, and its optimal conditions for solid state fermentation and phytase production were investigated. The results suggested that the optimal conditions of solid state fermentation were straw:rice bran ratio 8:2, medium initial pH 6.5, temperature 30 degrees C, culture duration 96 h, and moisture content 60%. Under the optimal conditions, LH374 could accumulate phytase up to 1,580 U x g(-1).