Screening and Identification of Oleaginous Yeasts from Fermentation of Tobacco Stem Extract

Using tobacco stem extract(TSE) as a sole substrate,12 strains of oleaginous yeasts were preliminarily isolated from fresh grapes by Sudan Black B staining method.Two strains,named as CC820 and CA815,with higher lipid yield and growing well in TSE were screened out by further shake flask fermentation experiments.By their colony,morphological,physiological and biochemical characteristics,CC820 was preliminarily identified as Candida sp and CA815 Rhodotorula sp.When stem was fermented at 30℃ for 5 days with an inoculant rate of 5%,a load capacity of 60/250 mL and 180 r/min,the maximum yield of lipid produced by CC820 and CA815 reached 3.53 g/L and 3.29 g/L,respectively.