以红曲霉AS3.972为出发菌株,经紫外诱变,筛选得到一株产高色价红曲色素的红曲霉菌株No.4,与出发菌株相比所产红曲色素总色价提高36.26%。通过单因素试验和正交试验,探讨pH值、温度及发酵时间对红曲霉菌株No.4产红曲色素总色价的影响。结果表明:影响红曲色素总色价的发酵因素由强到弱依次是pH值〉温度〉发酵时间,红曲霉菌株No.4产高色价红曲色素的最佳发酵条件为pH4.5、温度35℃、发酵时间6d,所产红曲色素总色价为286.16U/ml。
A high-yield Monascus strain, No.4 was obtained through mutation induced by UV from AS3.972, an original strain. Compared with its original strain, the newly-produced strain revealed an excellent color value with an enhancement of 36.26%. Effects of temperature, pH and fermentation time on total color value of No.4 strain were investigated by single-factor and orthogonal array design methods. Results showed that pH exhibited the strongest effect on color value of Monascus, and then followed by temperature and fermentation time. The optimal fermentation conditions to color value of No.4 strain were pH 4.5, 35 ℃ and fermentation for 6 days. The total color value of No.4 strain could reach 286.16 U/ml under these conditions.