Studies on Thermal Stability of Ginsenosides Aqueous Solution

OBJECTIVE To research the influence of heating-time on ginsenosides aqueous solution. METHODS HPLC was applied to determine the contents of ginsenoside Rg₁, Re, Rb₁, Rc and Rd, by means of different heating-time in Radix ginseng laterialis rubra concentrated liquid. RESULTS Within 6 hour of heating, the five types of ginsenosides showed different degrees of degradation. The content of the 20(S)-protopanaxdiol type ginsenoside Rb₁, Rc and Rd decreased significantly in the first 2 to 3 hours. Ginsenoside Rd had the lowest degradation rate compare with other four ginsenosides. The 20(S)-protopanaxtriol type ginsenoside Rg₁ and Re decreased rapidly within the first 3 hours, and then leveled off. CONCLUSION Under heating at atmospheric pressure, the main ingredients of in ginsenosides, Rg₁, Re, Rb₁, Rc and Rd, will keep falling as the heating prolonged. The descent rate becomes slow after the first 3 hours. Specifically, 20(S)-protopanaxtriol type ginsenoside is more sensitive than 20(S)-protopanaxdiol type ginsenoside.