Selection Of High Lovastatin Producing Fusant And Optimization Of The Fermentation Condition

Lovastatin is an inhibitor of the enzyme hydroxymethylglutaryl coenzyme A(HMG CoA) reductase that catalyzes the reduction of HMG CoA to mevalonate during synthesis ofcholesterol.lt is an effective and safe medicine that can be used to treat symptoms such as high cholesterol and high blood pressure . It is mostly synthesized by microorganism including Aspergillus terreus and Monascus spp..In this paper, to breed useful strains of Lovastatin-producing strain of Monascus anka, protoplasts of Aspergillus terreus CA99 with high yield of Lovastatin and Monascus anka M-3 with low yield of Lovastatin were fused. Selected from 363 fusants, 19 high-producing strains of Monascus anka were obtained. Ten of them gave more than 1.6 times the yield of the original strain.After fermentation experiment, the most suitable initial pH and carbon source and nitrogen source and mix nitrogen source of the fermentation medium were obtained. From the analysis of the result of orthogonal experiment, the best production medium with single and mix nitrogen source were obtained. The effect of K2HPO4-3H2O and MgSO4-7H2O to the synthesis of Lovastatin was researched. According to the above result ,the best fermentation medium was composed of 10%glucose, 0.5% beef extract, 0.25% (NH4)2SO4 , 2% tomato paste , 0.1% MgSO4-7H2O ,0.1%CaCO3. In this condition, the Lovastatin yield of the original strain and the most high-producing fusant is 796μg/ml and 1216μg/ml.