紫外诱变选育出芽短梗霉高产普鲁兰糖白化突变菌株

为了发酵获得无色素普鲁兰糖，对菌株Aureobasidium pullulan NG进行紫外诱变，成功获得一株高产普鲁兰糖的白化突变株UVMU3-1。将突变菌株与野生菌株比较发现，其菌体生长能力和分化能力未发生显著改变。突变菌株产出的多糖经红外光谱鉴定为普鲁兰糖，罐发酵实验表明突变菌株产糖能力强于野生菌株。在未经培养基和培养条件优化的情况下，罐发酵的糖转化率可以达到52.78%。突变株UVMU3-1可作为工业发酵普鲁兰糖的潜力菌株。

Breeding of a High Pullulan-producing Non-pigmented Mutant of Aureobasidium pullulans by UV-induced Mutagenesis

A non-pigmented mutant having enhanced ability to produce pullulan was successfully obtained using Aureobasidium pullulan NG as the original strain by UV-induced mutagenesis and was named as UVMU3-1. Compared with the original strain, the mutant strain UVMU3-1 displayed similar capability of growth and differentiation. The polysaccharide produced by the mutant strain was identified as pullulan by infrared spectroscopy. Tank fermentation experiments showed that the pullulan-producing capability of the mutant strain was higher than that of the original strain and that the 72 h cultivation of 200 mL of seed culture of the mutant in 5 L of YDA culture medium provided a glucose conversion of 52.78%. In conclusion, UVMU3-1 is a potential strain for pullulan production in industrial fermentation.