Fig. 4From: Bioconversion of vitamin D3 to bioactive calcifediol and calcitriol as high-value compoundsB. megaterium is used as a host cell for VD3 bioconversion. The electrons required for CYP activity are supplied by the endogenous cytochrome P450 reductase (CPR): NADPH-dependent diflavin reductase [76]. Quillaja saponin is used as a membrane-solubilizing agentBack to article page