L-精氨酸高产菌红曲霉的筛选及发酵初步研究

对不同样品中的真菌进行了L-精氨酸高产菌株的筛选,从红曲米中分离出1株高产L-精氨酸菌株红曲霉H13,其初始发酵液中L-精氨酸产量为1.67 g/L.通过单因素实验对其液体发酵进行研究.结果表明,最佳碳源是可溶性淀粉,最佳浓度为10％,最佳氮源是蛋白胨,最佳浓度为3％,最佳pH值4.5,温度30℃,种子培养时间为18 h,摇瓶装液量50 mL/250 mL.转速为120 r/min,发酵时间7d.在此条件下进行发酵培养,所得发酵液产L-精氨酸4.08 g/L,菌丝体干重为10.32 g/L,菌丝体中L-精氨酸含量为24.17 mg/g.

Screening of High L-Arginine Producting Strain of Monascus spp.and Preliminary Study on Its Fermentation

L-arginine-prcducing fungal strains were separated from different samples, and one L-arginine high-prod- ucting Monascu strain （H13） was isolated from red koji rice. The production of L-arginine was initially at 1.67 g/L and the fermentation medium formula and fermentation conditions were further studied through single factor experi- ments. The results showed that the optimum carbon source was soluble starch with optimal concentration at 10% , the optimal nitrogen source was peptone with optimal concentration at 3%, the optimal pH was at 4.5, temperature at 30 ℃. The seed cultivation time was 18 h. And the filling quantum of flask was 50 mL/250 mL, shaking at 120 r/min, and fermented for 7 d. Under these conditions the fermentation broth yielded L-arginine at 4.08 g/L with 10.32 g/L of dried weight mycelium, the content of L-arginine in the mycelium was 24.17 mg/g.