Optimization of fermentation conditions for 3-methylthiopropanol production by recombinant Saccharomycescerevisiaestrain

In order to improve the yield of 3-methylthiopropanol,the fermentation conditions of recombinant Saccharomyces cerevisiae strain were optimized by single factor test and orthogonal design.The optimal fermentation medium was determined as follows:methionine 5g/L,trace elements 2%(v/v),yeast extract 4g/L,peptone 12g/L,KH2 PO4 10g/L,K2 HPO4 2g/L,glucose 20g/L,G418 400μg/L.The optimal fermentation conditions were:inoculation volume 10%,50mL liquid culture in 250mL flask,temperature 30℃,rotation speed 200 r/min and initial pH 5.0.Under this optimum condition,the concentration of 3-methylthiopropanol of 4.38g/L was achieved,which was 3.5times higher than before.