Effect on the Synthesis of 1,3 propanediol of Organic acids in the Two-stage Fermentation / 中国生物工程杂志

Effect of organic acids on the synthesis of 1,3 propanediol was studied.The adsorption of organic acids from glycerol fermentation liquor by ion-exchange resins was investigated.The results showed that organic acid and 1,3 propanediol production was in negative relationship.The static adsorption showed that ion-exchange resin 005 had the best adsorption abilities of the organic acids in the glycerol fermentation liquor.It was showed that the yield of 1,3propanediol increased by 166% after the extraction of organic acids from glycerol fermentation liquor and the convertion rate increased by 34%.

SCREENING AND MUTATING A RAW STARCH-DIGESTING GLUCOAMYLASE STRAIN / 微生物学通报

strains that could produce raw starch-digesting glucoamylase were isolated from soil and mildewed rice.The highest raw starch-digesting glucoamylase activity strain named OR-1 was identified as Rhizopus.sp.The raw starch-digesting glucoamylase activity of the strain is 90U/mL.Through UV and NTG mutagenesis,the raw starch-digesting glucoamylase activity raised to 200U/mL and 325U/mL respectively.The RDA were 70% and 65% respectively.