Effect Of Metal Ion On Lipid Fermentation By Trichosporon Cautaneum And Lipid Fermentation Using Corncob Residual

This research includes two parts, one is about the effect of metal ions on lipid fermentation by Trichosporon cautaneum, the other one is about microbial lipid production from corncob residue.First, Seven metal ions were tested in medium with the same C7N for microbal lipid production. Fe2+and Fe3+can promote the growth of Trichosporon autaneum CX1, and do not reduce the yeast oil-bearing rate. When the concentration of FeCl3·OH2O was0.15g/L, the dry cell weight (DCW), lipid content and lipid were11.5g/L,33.2%and4.0g/L, increasing by21%,11%and32%, respectively.Secondly, Corncob residue is a solid waste from the xylose production process using corncob, and can directly be hydrolyzed into monosaccharides by cellulase. Trichosporon cutancum20271was found to grow in the hydrolysate and accumulate microbial lipid. The medium composition was optimized by testing varioust ingredients for improvement of lipid productivity. As a result, corn steep liquor (CSL) was found to improve the yeast growth rate in hydrolysate. With the increase of CSL. yeast growth rate and lipid production has improved significantly, and lipid content of the yeast didn’t change. When sugars’ concentration was higher in hydrolysate, the culture resulted in (DCW). lipid titer, lipid content and lipid productivity of38.4g/L,12.3g/L,32%and0.064g/L/h respectively.