用于微生物油脂发酵的木薯淀粉水解工艺的优化

为了提高木薯淀粉的发酵产脂能力,采用正交实验和均匀设计法对木薯淀粉酶法水解工艺进行了优化,结果表明α-淀粉酶量、糖化酶量和液化温度对木薯淀粉水解有显著影响。当淀粉酶量为756 U/g,糖化酶量为602 U/g,液化温度为92°C,其水解DE值达到97.3%。以该水解液进行皮状丝胞酵母B3(T.cutaneum B3)油脂发酵时,其生物量和油脂产量分别为16.38 g/L和7.22 g/L,比葡萄糖作为碳源的生物量和油脂产量高46.25%和41.12%,利用木薯淀粉水解液作为新型发酵碳源生产微生物油脂是一种理想的途径。

Study on Hydrolysis Process of Cassava Starch Used for Microbial Lipid Fermentation

In order to improve the lipid production of cassava starch,the process of cassava starch hydrolysis(CSH) was optimized using orthogonal experimental design and Uniform design.The results showed that the content of α-amylase and glucoamylase and the liquefaction temperature significantly influenced cassava starch amylolysis.The dextrose equivalent value was up to 97.3% when content of α-amylase and glucose amylase and liquefaction temperature were 756 u/g,602 u/g and 92℃,respectively.While the CSH was used as a carbon source,the biomass and total lipid content of Trichosporon cutaneum were 16.38g/L and 7.22 g/L respectively,which increased by 46.25% and 41.12% as compared with those using glucose as a carbon source.Therefore,cassava starch hydrolysis,as a novel carbon source,is an ideal route to produce microbial lipid.