Biotransformation of progesterone by the green alga Chlorella emersonii C211-8H

2β-Hydroxyprogesterone, 6β-hydroxyprogesterone, 9α-hydroxyprogesterone, 14α-hydroxyprogesterone, 16α-hydroxyprogesterone and 21-hydroxyprogesterone are the main bioproducts in the progesterone bioconversion by axenic cultures of Chlorella emersonii C211-8h. After 30 days 6β,9α-dihydroxyprogesterone, 6β,21-dihydroxyprogesterone and 16α,21-dihydroxyprogesterone are also formed. In acid conditions the reaction is slower and 2β-hydroxyprogesterone and 16α-hydroxyprogesterone have not been found among the bioproducts. In hyperhaline conditions the yields are generally lower and testololactone is also formed. Copyright © 1996 Elsevier Science Ltd. All rights reserved.