Mutation breeding of high 9α-hydroxy-androst-4-ene-3,17- dione transforming strains from phytosterols and their conversion process optimization / 生物工程学报

ABSTRACT

In order to improve transformation efficiency of phytosterols into 9α-hydroxylation of 4-androstene-3,17-dione (9α-OH-AD) by Mycobacterium sp. LY-1, we studied the strains breeding using atmospheric and room temperature plasma (ARTP) technology and optimized their conversion process. A high production strain named C33 with a good genetic stability was selected and the product molar yield reached to 15.5%, 34.8% higher than that of original strain with 15 g/L phytosterols. Furthermore, the fermentation medium was optimized through the design of orthogonal experiment. Besides, oil-water bidirectional transformation system was set up to improve the 9α-OH-AD molar yield of mutant strain C33. With adding 12 mL soybean oil to each 1 g phytosterols, the molar yield of 9α-OH-AD reached 47.0%, which increased twice than that of control (15.5%).