Genistein has been regarded as one important soy isoflavone with multiple health benefits, whereas its applications are limited by the low hydrophilicity. To improve the water solubility, codon optimized cyclodextrin glycosyltransferase from Paenibacillus macerans was employed for genistein transglycosylation in this study. At least four transglycosylation products were produced and identified by HPLC and LC-MS: genistein monoglucoside, diglucoside, triglucoside, and tetraglucoside derivatives. Obviously, the yields of genistein monoglucoside and genistein diglucoside exhibited great superiority compared with other two products. To maximize the yield of genistein diglucoside, various reaction conditions such as genistein dissolvents, glycosyl donors, substrates concentrations and ratios, enzyme concentrations, reaction pH, temperature, and time were optimized. Finally, the yield of genistein diglucoside was enhanced by 1.5-fold under the optimum reaction system. Our study demonstrates that the production of genistein diglucoside could be specifically enhanced, which is one important genistein derivative with better water solubility and stability.
Keywords: Co-α-CGTase; Genistein; Genistein diglucoside; Optimization; Solubility.