Microbial hydroxylation of cinobufagin by Mucor spinosus

Mucor spinosus has been employed for the biotransformation of cinobufagin ( 1 ) to afford three metabolites. On the basis of their physico-chemical data, the structures of the transformation products have been characterized as 1beta-hydroxy-cinobufagin ( 2 ), 12beta-hydroxy-cinobufagin ( 3 ) and 1beta,12beta-dihydroxy-cinobufagin ( 4 ), of which metabolites 2 and 4 are new compounds. In vitro cytotoxic activities of the biotransformation products and the substrate-cinobufagin have been assayed against four tumor cell lines of Bel 7420, BGC 823, HeLa and HL 60; they all showed cytotoxic activities.Plant SciencesChemistry, AppliedChemistry, MedicinalPharmacology & PharmacySCI(E)PubMed7ARTICLE3225-229