高产红色素及糖化酶红曲菌株的诱变选育

Mutation Breeding of Monascus Strains with High Red Pigment and Glucoamylase Production

目的:通过诱变手段提高红曲菌株产色素能力和糖化酶活力。方法:采用平板稀释分离法从古田平湖红曲米中分离筛选到1株高产红色素和糖化酶的红曲霉菌株C26。以C26作为出发菌株,经紫外和紫外-Li Cl复合诱变两轮诱变,选育得到1株红色价和糖化酶活力明显提高的突变菌株183-3。结论:该突变株液态发酵红色价达138.30 U/m L,糖化酶活力达76.34 U/m L,分别比出发菌株提高了107%和51%;接种于大米中进行固态发酵,红色价和糖化酶活力分别达到7 512 U/g和1 337 U/g。结合形态学和ITS序列分析,鉴定183-3菌株为紫色红曲霉。

Objective： Monascus strains were mutated to increase red pigment production and glucoamylase activity. Method： By usingplate dilutionmethod, Monascus strain named C26 was isolated and purified from red yeast rice provided by Gutian Monascus Industry Association, with high red pigment production and glucoamylase activity. Using Monascus strain C26 as an original strain, a mutated strain named 183-3 was obtained by UV and UV-LiC1 treatment. Conclusion： The color value and the glucoamylase activity of the mutant strain reached 138.30 U/mL and 76.34 U/mL by liquid fermentation, which were 107% and 51% higher than that of the original strain, respectively; The yield of pigment and glucoamylase were 7 512 U/g and 1 337 U/g when strain 183-3 was inoculated withriee by solid fermentation. It was identified as Monascus purpureus based on its morphological observation and ITS sequence analysis.