Abstract
The microbial transformation of vitamin D-3 (1) by the fungi Candida maltosa R42 and Botrytis allii NRRL 2502 was investigated. Incubation of compound 1 with C. maltosa R42 and B. allii NRRL 2502 produced the same three more polar metabolites in small yields. The main metabolite was identified as 1 alpha-hydroxyvitamin D-3 (2). This biotransformation has utility as a possible tool for the production of 1 alpha-hydroxyvitamin D-3 from the readily available vitamin D-3 for patients with compromised kidney function.