长孢被孢霉利用淀粉质原料发酵产微生物油脂

Fermentation of microbial lipid by Mortierella elongate with starch

通过研究长孢被孢霉（Mortierella elongate）的发酵过程，并采用摇瓶分批补料发酵模式考察了起始补料时间及补料基质对长孢被孢霉合成微生物油脂的影响。结果发现该菌株合成油脂主要在发酵48～96 h进行，且N源对菌株的生长有促进作用，采用限氮补料发酵可大幅度提高微生物油脂的产量。最适培养条件：可溶性淀粉20 g/L，玉米浆3 g/L，补料起始时间为发酵48 h，单次补加可溶性淀粉4 g。在此条件下，油脂产量较不补料时增加了521.74 mg，增长率为237.1％。

The fermentation process of Mortierella elongate and a fed-batch strategy were investigated.The results showed that the synthesis of lipid was conducted during 48 h to 96 h,and nitrogen sources could promote the growth of the strains.Nitrogen-limited fed-batch process improved the production of lipid.The optimum concentration of carbon and nitrogen sources was 20 g/L,and 3 g/L,respectively.Under these conditions,feeding of 4 g soluble starch at the third day of the fermentation could increase the lipid by 521.74 mg with a growth rate of 237.1%.