Bioconversion of ginsenoside Rd to ginsenoside M1 by snailase hydrolysis and its enhancement effect on insulin secretion in vitro.

In the present work, we report efficient production of ginsenoside M1 (G-M1) from ginsenoside Rd (G-Rd) by snailase hydrolysis using response surface methodology (RSM). During investigation of the hydrolysis of ginsenoside Rd by various glycoside hydrolases, snailase showed a strong ability to transform G-Rd into G-M1 with 100% conversion. RSM was used to optimize the effects of the reaction temperature, enzyme load, and reaction time on the conversion process. Validation of the RSM model was verified by the good agreement between the experimental and the predicted values of G-M1 conversion yield. The optimum preparation conditions were as follows: temperature of 41.0 degrees C; enzyme load of 17.5%; reaction time of 18 h. The determined method may be highly applicable for the enzymatic preparation of G-M1 for medicinal purpose. Furthermore, the effect of G-M1 on insulin secretion in MIN6 pancreatic β-cells was investigated.