Study of the transformation of DHEA by white streptomyces immobilized by hollow calcium alginate

Objective Producing hydroxylated DHEA with antioxidant and anticancer activity by bioconversion methods. Methods Through the hollow calcium alginate to immobilize Streptomyces albus to transform DHEA. And through the optimization of the immobilization and transformation conditions as well as the second transformation of the immobilized bacteria to get the high production of hydroxylated DHEA. Results The immobilized bacteria had the transformation activity on DHEA, and we got the high production of hydroxylated DHEA by the second transformation of immobilized bacteria. The best transformation conditions of immobilized bacteria was:immobilized the Streptomyces albus which had grown for two days,temperature 35℃ , pH 7,rotati on speed 150r/min,transformation time 3days. Conclusion It is possible for immobilized bacteria to transform DHEA,and this method has wide industrial application value.