Fermentation Production Of Coenzyme Q₁₀ By Schizosaccharomyces Pombe Linder

Coenzyme Q10comprises a benzoquinone ring linked to a polyisoprenyl chain of10units. Coenzyme Q10is an essential electron carrier in the mitochondrial respiratory chain, and widely used as an essential component of ATP generation in the oxidative phosphorylation process and as an lipid-soluble antioxidant preventing lipid peroxidation.Firstly, the components of the fermentation medium were optimized. The optimum medium consisted of glucose4%, yeast extract1.25%, peptone1.25%, K2HPO40.05%, KH2PO40.05%, MgSO4·7H2O0.03%, and the optimum cultivation time was72hours.Secondly, the influence of P-ionone and ergosterol on the growth and the yield of Coenzyme Q10in yeast were investigated. The results indicated that p-ionone had the stimulative effect on the biosynthesis of Coenzyme Q10in yeast, and28.3%increase of the Coenzyme Q10content in the cell was observed when the concentration of β-ionone in the medium was0.208X10"3mol/L. Little ergosterol also had the same effect with β-ionone, while31.3%increase of the Coenzyme Q10content in the cell was observed when the concentration of ergosterol in the medium was0.15×10-4mol/L. However, the biosynthesis of Coenzyme Q10was inhibited when the concentration of ergosterol was0.60×10-4mol/L Addition of β-ionone and ergosterol to the medium simultaneously resulted in36.1%increase over the control. The results showed that the cell could effectively accumulate more Coenzyme Q10with the addition of P-ionone and ergosterol to the medium.The methods of extracting Coenzyme Q10were investigated in this thesis. The optimum method was that the cells were pretreated with HCl at hot water, then extracted with acetone. The optimum temperature and time of pretreating with HCl were90℃and80min, and that of extracting Coenzyme Q10with acetone were room temperature and2.5hours.Finally, the metabolic regulation effects of the fermentation and non-fermentation carbon source and the temperature on the yield of Coenzyme Q10in yeast were investigated. The results showed that different kinds of carbon source and culture temperature all had the influence for the yield of Coenzyme Q10.