Spectrophotometric methods for monitoring the microbial transformation of steroids. I. Determination of 9-alpha-fluorohydrocortisone and 9-alpha-fluoro-16-alpha-hydroxyhydrocortisone in fermentation broths.

A method has been devised for the determination of 9alpha-fluorohydrocortisone and 9alpha-fluoro-16alpha-hydroxyhydrocortisone in fermentation broths. The method involves extraction of the two steroids from the broth with ethyl acetate, separation through the formation of the water-soluble borate complex of the vicinally hydroxylated steroid, and estimation of each steroid spectrophotometrically.