Enzymatic Synthesis of Puerarin Glucosides Using Cyclodextrin Glucanotransferase with Enhanced Antiosteoporosis Activity

Puerarin ( PU ) is the most abundant isoflavone from the root of Pueraria lobata and exhibits a broad range of pharmacological activities. However, poor water solubility and low bioavailability limit its use. Enzymatic transglycosylation is emerging as a new strategy to improve the pharmacodynamic and pharmacokinetic properties of natural products for drug development. In this study, three PU glucosides ( PU-G , PU-2G , and PU-3G ) were synthesized by using a cyclodextrin glucanotransferase from Bacillus licheniformis with PU as the acceptor and α-cyclodextrin as the sugar donor. The transglycosylation products were isolated and structurally identified by mass spectrometry and nuclear magnetic resonance. The water solubilities of PU-G , PU-2G , and PU-3G were 15.6, 100.9, and 179.1 times higher than that of PU , respectively. Moreover, the antiosteoporosis activities of these glucosides were tested, and PU-G was found to show much more potent antiosteoporosis activity as compared to the original PU .