Improving enzymatic production of ginsenoside Rh2 from Rg3 by using nonionic surfactant

In this study, several nonionic surfactants were tried to improve the enzymatic hydrolysis of ginsenoside Rg3 into Rh2 which was catalyzed at 50 degrees C and pH 5.0 by a crude glucosidase extracted from Fusarium sp. ECU2042. Among the biocompatible nonionic surfactants, polyethylene glycol 350 monomethyl ether was shown to be the best. After optimizing some influencing factors on the reaction, the conversion of Rg3 (5 g/l) with 10 g/l crude enzyme reached almost 100% in the presence of the nonionic surfactant (7.5%, w/v), which was 25% higher than that in buffer without any surfactant. Furthermore, the enzyme stability was affected faintly by the surfactant.