【摘要】 木糖的有效利用是木质纤维素全利用的基础。为了获得高效利用木糖产油的高山被孢霉菌株,通过多轮氮离子束诱变,筛选出一株有效利用木糖的产油高山被孢霉I502-8(Mortierella alpina I502-8,MAI502-8),并研究了以葡萄糖/木糖(W/W,5/3)组成的混合糖为碳源,突变株生长和油脂积累的特性。采用单因子和正交实验对培养基组成和发酵条件进行了优化,结果表明,诱变菌在温度28℃,pH 8.0,接种量8%,装液量30%,蛋白胨0.76%和豆粕1%,分批补糖的最优发酵条件下发酵9d,生物量和菌体油脂积累量分别达29.8g/L和11.7g/L,较出发菌提高了2.59倍和2.05倍,同时原料糖利用率达到99.4%。更多还原

【Abstract】 Efficient use of xylose is the basis for using lignocellulose completely.To obtain an industrial strain with a higher microbial lipids yield,the strain Mortierella alpina was mutated through many times of nitrogen ion beam implantations and the mutant strain Mortierella alpina I502-8 was obtained.The properties of growth and lipids accumulation from glucose and xylose(W/W,5/3) were also studied.The medium composition and some fermentation parameters were studied by cross test and single factor experiments.The optimal conditions are as follows:tryptone 0.76%,bean powder 1.0%,initial pH 8.0,temperature 28℃,inoculation quantity 8%and loading volume 30%.Under optimal conditions,the maximum yield of biomass and microbial lipids reached 29.8 g/L and 11.7 g/L,respectively,which was 2.59 times and 2.05 times of those cultured in the original medium,after 9 days fed-batch co-fermentation in shakeflask. And 99.4%of the mixed sugar used up during co-fermentation.更多还原