PURPOSE:To produce the subject derivative in high yield by culturing a mutant K-3 strain of Rhodococcus equi in a specific medium and adding a cholestan steroid compound as a substrate. CONSTITUTION:A Rhodococcus equi mutant K-3 (FERM 9880, Rhodococcus equi MIL-1045) or Rhodococcus equi is inocculated in a medium containing higher fatty acid of 10-19 carbon atoms such as rich salt such as cupric salt such as CuCl2 and cultured at 27 deg.C for 22hours. The culture mixture is combined with a cholestane steroid such as beta-cytocholesterol to effect the reaction for about 7days whereby the subject product is obtained. The reaction product is extracted, concentrated, and purified to give 20-carboxypregnan derivative.
展开▼
