木糖的乙醇发酵一直被视为木质纤维原料生物转化产生乙醇的关键因素, 休哈塔假丝酵母(Candida shehatae)是木糖发酵性能较好的天然酵母之一。对Candida shehatae HDYXHT-01进行了氦氖激光诱变和NTG诱变, 力求选育出发酵木糖产乙醇能力强的菌株。氦氖激光诱变得到的突变株HN-3乙醇产量为17.03 g/L, 乙醇得率达到0.3393 g/g, 相比原始菌株提高20.36 %。再对HN-3进行NTG诱变, 得到的突变株NTG-2乙醇产量为24.20 g/L, 相比HN-3提高42.10 %。进而对NTG-2菌株进行了摇瓶48 h连续发酵试验, 测得其乙醇产量、木糖利用率、乙醇得率和乙醇产率分别达到24.16 g/L, 69.26 %, 0.4360 g/g和0.7075 g/(L·h)。

Ethanol fermentation of xylose has been known as the key factor for lignocellulose to produce ethanol. Candida shehatae was one of the better natural yeast with the capability to ferment xylose. Combined mutagenesis with He-Ne laser and NTG were studied on Candida shehatae HDYXHT-01 in order to select strains of high ethanol by ferment xylose. After the mutagenesis with He-Ne laser, the HN-3 was obtained with ethanol production and yield rate were 17.03 g/L and 0.3393 g/g respectively, which was increased by 20.36 percent compared with the original strain. The HN-3 was continuous mutagenesis by NTG, an mutant strain NTG-2 with ethanol production of 24.20 g/L was selected, which was increased by 42.10 percent compared with HN-3. The NTG-2 was incubated with shaking in flask for fermentation for 48 h, the ethanol production, xylose utilization, ethanol yield rate and ethanol production rate reached 24.16 g/L, 69.26 %, 0.4360 g/g and 0.7075 g/(Loh), respectively.