高产花生四烯酸高山被孢霉菌株的诱变筛选

Mutation breeding and screening of high arachidonic acid yielding strain of Mortierella alpina

以高山被孢霉(Mortierella alpina)CFCC 88447为出发菌株,利用紫外线-氯化锂复合诱变、硫酸二乙酯化学诱变、微波诱变等方式对出发菌株进行诱变育种,结果表明紫外线-氯化锂复合诱变和硫酸二乙酯化学诱变有利于筛选高产花生四烯酸的菌株。将诱变后的菌株依次通过乙酰水杨酸平板、碘乙酸平板、10℃低温培养、红四氮唑(TTC)水溶液显色、摇瓶发酵等条件进行筛选,最终获得花生四烯酸的高产菌株M-TY-Ⅲ2,其生物量为30.21 g/L,总油脂含量为13.19 g/L,花生四烯酸产量为3.81 g/L,花生四烯酸产量比出发菌株提高了141%。传代实验表明,高产菌株M-TY-Ⅲ2具有良好的遗传稳定性。

Using MortiereUa alpina CFCC 88447 as the original strain, ultraviolet-LiC1, diethyl sulfate （DES） and micro- wave were employed for mutation breeding, respectively. The results showed that the ultraviolet-LiC1 composite mutagene- sis and DES mutagenesis were found to improve arachidonic acid yield. Through screening with acetylsalicylic acid plate, iodoacetic acid plate, low temperature（ 10℃） cultivation, chromogenic reaction with 2,3,5-triphenyltetrazolium chloride （Trc） and shake-flask fermentation, a mutant with high AA prodution was obtained and named M-TY-Ⅲ2. In the shake culture by M-TY-Ⅲ2, the biomass, total lipid and arachidonic acid yield reached 30.21 g/L, 13.19 g/L and 3.81 g/L which was increased by 141% if compare with the yield by the original strain. Meanwhile, the mutant M-TY-Ⅲ2 exhibi- ted high genetic stability.