小克银汉霉γ-亚麻酸高产菌株的快速筛选和发酵条件研究

Fast selection and fermentation condition of high-yielding strains of Cunninghamella echinulata producing gamma-linolenic acid (GLA)

以小克银汉霉C0为出发菌株,经过5-氟尿嘧啶和紫外线复合诱变,采用抗失水苹果酰肼与抗低温(15℃)相结合的筛选方法,获得一株生产性能比出发菌株显著提高的突变株C23。采用5L全自动发酵罐对小克银汉霉C23发酵生产γ-亚麻酸的pH值控制和补料工艺进行研究,发现将发酵液pH值维持在5.5,当发酵进行到60h、84h、108h时,分别补糖15g/L,发酵192h后收获,结果生物量、油脂产量和γ-亚麻酸产量分别达到49.88g/L、21.93g/L、2.69g/L。

A high-yielding mutant Cunninghamella echinulata C23 producing y-linolenic acid was successfully obtained when the original strain Cunninghamella echinulata Co was treated by 5-FU and UV, and by the screening methods of resisting maleic hydrazide and 15℃ low temperature. The pH control and the feeding technique of y-linolenic acid production were studied by using 5L completely automatic fermentor. The biomass, lipid yield and y-linolenic acid yield of C23 were 49.88 g/L, 21.93 g/L and 2.69 g/L respectively when the pH value of liquid media maintained 5.5 and the 15g/L glucose was fed in 60h, 84h, 108h of fermentation, and total cultivation time was 196h.