Screening Methodology Of Microbial Lipid Accumulation Strain And Lipid Fermentation From Lignocellulose Feedstock

Microbial lipid derived from lignocellulosic biomass is a important way for biodiesel and aviation kerosene production.Hydrolysate syetem producted from lignocellulose is a challenge for cell growth and lipid accumulation after biorefinery.Previous research proved Trichosporon cutaneum is an oleaginous yeast which possess high tolerance to inhibitors derived from lignocellulose and superior microbial lipid accumulation capacity.Intracellular product accumulation and can't be labeled,cell morphology is not be direct related to lipid concentration are main difficulties for oleaginous microorganism screening.This study is focused on obtaining one strain with high lipd content exhaustively.On account of appearance of cell density,one strain called T.cutaneum MS 28 that can accumulate high concentration lipid was obtained after long term centrifugal screeing and adaption evolution.The reasons focusing on differences between T.cutaneum MS 28 and.cutaneum ACCC 20271 were investigated.Compared to T.cutaneum ACCC 20271,mutation strain.cutaneum MS 28 have superior lipid fermentation performance,more lipid bodies,and relative transcription level of genes about triglyceride synthesis are up regulated.Meanwhile,cell volume of T.cutaneum MS 28 has been enlarged which can accommodate more lipid bodies.The relative transcription levels of genes encoding endoglucanase and MAPK pathway have been up regulated significantly.Finally,the mechanism and general applicability of centrifugal screening method has been investigated preliminarily.Lignin is the major recalcitrant component of lignocellulosic biomass.This part is about lipid accumulation potential of lignin derived phenolic aldehyde by T.cutaneum ACCC 20271.Only 4-hydroxybenzaldehyde behaved the effective conversion to lipid.A long term fed batch fermentation of 4-hydroxybenzaldehyde as the sole carbon by T.cutaneum ACCC 20271 was conducted and 0.85 g/L of lipid was accumulated.Chemical and physical mutation is a good way that make it is possible vanillyl acid and syringate can be degraded totally along with evolutionary adaption.T.cutaneum MS 28 which accumulate high titer lipid was obtained after high speed centrifugal screening;T.cutaneum ACCC 20271 degrading 4-hydroxybenzaldehyde totally provides the new insight for microbial lipid production.Above results are meaningful for lignin utilization and biofuel production such as biodesel and long chain hydrocarbon.