One-Pot Production of 3-Hydroxyphloretin from Phlorizin by Bacillus subtilis Whole-Cell System Expressing CYP102A1

3-Hydroxyphloretin is a potent inhibitor for adipocyte differentiation and lipid accumulation and is a promising functional health supplement. Here, the one-pot bioconversion process for 3-hydroxyphloretin production from phlorizin, the most abundant glucoside of phloretin in apples, was investigated using Bacillus subtilis expressing CYP102A1 via two-step enzymatic reactions. β-Glucosidase activity in B. subtilis catalyzed the efficient removal of the glucose portion of phlorizin to produce phloretin, and CYP102A1 converted the phloretin to 3-hydroxyphloretin by regioselective hydroxylation. The CYP102A1 gene was integrated into the chromosome of B. subtilis for stable and sustainable expression during large-scale fermentation. The optimal whole-cell bioconversion for 3-hydroxyphloretin production from phlorizin was 20 g of cells L–1 and 10 mM phlorizin at 37 °C, 240 rpm, and pH 7.5. As a result, 1.45 mM 3-hydroxyphloretin was successfully produced by B. subtills expressing CYP102A1. This study provides a sustainable platform for the efficient production of 3-hydroxyphloretin from phlorizin.