Studies On Microbial Transformation Of Androst-4-ene-3,17-dione By Strain A35b

Androst-4-ene-3,17-dione(4AD)is one of the important intermediates which is used for synthesizing steroidal drugs.Biological transformation is an effective method in the synthesis of drug lead compounds.The microbial transformation of 4AD was studied in this paper,obtaining the following results.A strain A35 b with ability to convert 4AD was selected out though screening of 30 strains of fungi.The conversion rate was 100% when the substrate concentration was 0.5(g/L),transformation time 7d.Two biotransformation products were obtained and characterized as 11-Hydroxyandrost-4-en-3,17-dione and 11α-Hydroxytestosterone after expand training of strain A35 b.The strain A35 b was identified as Colletotrichum sp.according to the analysis of 18 S r DNA gene sequence.The factors which affect the transformation of strain A35 b,such as substrate concentration,transformation time,medium initial p H,glucose concentration were optimized,the results show that the best conditions for obtaining 11-Hydroxyandrost-4-en-3,17-dione is substrate concentration of 0.5 g/L,conversion time 7 day,glucose concentration 10 g/L and the initial p H value of natural.