Patent ID: 8530205

Claim:
A buffer composition for promoting production of calcitriol or calcifediol by biocatalytic reaction of growth-arrested cells of Pseudonocardia autotrophica , the buffer composition consisting of 0.01 to 0.3% (w/v) at least one metallic compound selected from the group consisting of FeCl 2 , FeCl 3 , FeSO 4 , MnCl 2 , and ZnSO 4 , 1 to 10% (w/v) of at least one organic solvent selected from the group consisting of ethanol, methanol, acetone, and dimethyl sulfoxide (DMSO), 0.1 to 5% (w/v) of cyclodextrin, 0.01 to 1% (w/v) of tris(hydroxymethyl)aminomethane, 0.01 to 1% (w/v) of sodium succinate, 0.01 to 1% (w/v) of sodium chloride, 0.001 to 0.5% (w/v) of magnesium chloride, and a residual quantity of water.