Screening and Production Optimization of a New Organic Solvent-Tolerance Fungal Lipase

A novel fungus which produced lipase extracellularly was isolated from soil. The strain was named after Candida tropicalis SD7 based on morphological f eatures and ITS1-5.8S-ITS4 region sequences of ribosomal RNA. The fermentation conditions were optimized in order to improve lipase production of the strain. The maximum lipase activity was achieved at 72h. The optimum lipase production was observed in the medium with glycerol as carbon source and peptone as nitrogen source through submerged fermentation at 30° C and initial pH 7.0. The lipase showed stability in the presence of hydrophobic organic solvents such as methylbenzene, petroleum ether, isooctane and n-hexane. It was moderately stable in polar solvents, including DMSO, acetone, acetonitrile and methanol.