【摘要】 为筛选较高色价和较低橘霉素的优良红曲霉菌株,利用紫外线和氯化锂对Monascus purpureusGX菌株进行复合诱变,结果:在紫外线照射时间为80 s和氯化锂浓度为1.0‰的条件下,获得了1株橘霉素(Citrinin)产量低、色价中等的突变菌株M.S 9。突变株M.S 9发酵的红曲米色价为873 U/g,Citrinin含量为18 mg/kg。将该菌株连续培养5代后,其红曲米色价为892 U/g,Citrinin含量为26 mg/kg。以色价为目标函数(y),初始pH值(x1)、初始温度(x2)、接种量(x3)、乙醇浓度(x4)、豆油浓度(x5)为试验因子,选用二次饱和D-最优设计法(R521D)设计试验方案。经软件统计分析得到红曲米色价与各试验因子的最优回归方程和色价达到理论最高值1 411 U/g时,各因素的最佳组合为:初始pH 3.8,初始温度26.8℃,接种量13.5%,乙醇浓度0.5%,豆油浓度1%。经验证,各因子为最佳组合时,红曲米色价为1 423 U/g。更多还原

【Abstract】 Monascus purpureus GX was induced multiplex mutation with UV and LiCl for screening a mutant with high yield of pigment and low citrinin content.The results show that a mutant strain,M.S 9,obtained by UV exposure for 80 s and on 1.0‰ LiCl medium has low citrinin content and mid pigments value.The citrinin content and the pigments value are 18 mg/g and 873 U/g respectively in red rice fermented by M.S 9.After incubation for five continuous generation of S 9,its red rice contains 26 mg/kg citrinin and with pigments value of 892 U/g.With R521D experimental design,data analysis with SPSS and DPS indicates that the best factors combination is original pH 3.8,original temperature at 6.8℃,13.5% inoculation,0.5% alcohol and 1% bean-oil when the pigments value reaches the highest 1 411 U/g theoretically in the best regression equation.The pigments value in the S9 fermenting red rice is verified as 1 423 U/g under the best factors combination above.更多还原