曲酸生产菌的复合诱变选育

以生产菌株米曲霉（Aspergillus oryzae）w-56为出发菌株,经2次紫外线、2次60Co多重复合诱变处理,选育获得曲酸生产菌UR28,生产发酵周期由原来的130h缩短至65h,曲酸产量由原来的36g/L,提高到68g/L,比出发菌株提高了88.9%。实验证明采用复合诱变,能有效改变菌株对诱变因素的敏感性,提高突变率,逐步提高突变株的产酸水平。

Compound Mutation Breeding of Kojic Acid Productive Strain

Mutant（UR28） of producing high-yield Kojic acid was screened from productive strain Aspergillus oryzae w-56 after treated with UV two times, γ-ray of ^60Co two times. The period of fermentation was shorten to 68h from 130h. The Kojic acid production level reached up to 68g/L, increasing by 88.9% compared with original strain＇s 36g/L. The experiments showed that compounding mutation can alter original strains sensitivity to mutagnic agents, increase mutation frequency and raise kojic acid yield.