Enzymatic transformation of ginsenosides Re, Rg1, and Rf to ginsenosides Rg2 and aglycon PPT by using β-glucosidase from Thermotoga neapolitana

Objectives: To enzymatically transform protopanaxatriol by using β-glucosidase from Thermotoga neapolitana (T. neapolitana) DSM 4359.

Results: Recombinant β-glucosidase was purified, which molecular weight was about 79.5 kDa. High levels of ginsenoside were obtained using the follow reaction conditions: 2 mg ml^-1 ginsenoside, 25 U ml^-1 enzyme, 85 °C, and pH 5.0. β-glucosidase converted ginsenoside Re to Rg2, Rf and Rg1 to APPT completely after 3 h under the given conditions, respectively. The enzyme created 1.66 mg ml^-1 Rg2 from Re with 553 mg l^-1 h^-1, 0.85 mg ml^-1, and 1.01 mg ml^-1 APPT from Rg1 and Rf with 283 and 316 mg l^-1 h^-1 APPT.

Conclusions: β-glucosidase could be useful for the high-yield, rapid, and low-cost preparation of ginsenoside Rg2 from Re, and APPT from the ginsenosides Rg1 and Rf.