Microbiological production of radioisotopically labelled 16 alpha-hydroxylated steroids in trace quantities

[14-14C]16 alpha-Hydroxy-C-18- and C-19-steroid hormones were obtained in good yields by microbiological hydroxylation of correspondingly labelled steroids by Streptomyces roseochromogenes NRRL B-1233. Trace quantities of the labelled substrates were incubated on a rotary shaker (220 rpm) at 27 degrees C. The radioactive products were chromatographically separated, identified and the radiochemical purity was established by isotopic dilution analysis. The specific activities of 16 alpha-hydroxy-steroids obtained were assumed to be the same as those of the substrates, namely, 57.5 mCi/mmole for 16 alpha-hydroxy-4-androstene-3,17-dione, 57.5 mCi/mmole for 5-androstene-3 beta,16 alpha,17 beta-triol, 57.5 mCi/mmole for 16 alpha-hydroxy-dehydroepiandrosterone, 55.7 mCi/mmole for 16 alpha-hydroxy-estrone, and 57.5 mCi/mmole for 16 alpha-hydroxy-testosterone.