植酸酶高产菌株的诱变选育

无花果曲霉是一种可以产植酸酶的菌株,其代谢产物植酸酶可以将有机植酸磷降解为无机磷。以此菌株为出发菌株,确定了它的最适pH值为1.3~1.4,最适温度为55~60℃。同时,为获得高酶活的突变株,进行亚硝基胍和紫外线处理,经初筛得到99株高效突变株,再经复筛和传代试验,得到1株植酸酶活性是出发菌株2.47倍的突变株NTG-23。

Mutation Breeding of Phytase High-Yielding Strain

Aspergillus ficuum is a strain that could produce phytase. Its metabolites could degrade organic phosphate into inorganic phosphate. It was taken as a starting strain to begin with the study. And confirmed pH 1.3 ~ 1.4 was the most suitable value and optimum temperature was 55 -60 ℃ respectively. In order to obtain mutant strain with high enzymatic activity, UV and NTG treatment were taken and obtained 99 mutant strains with highly effective through primary screening. One strain （NTG-23） was obtained through secondary screening and generation passing experiment, its enzymatic activity was 2.47 times of the starting strain.