Metabolic activities of ginseng and its constituents, ginsenoside Rb₁ and Rg₁, by human intestinal microfora

To evaluate the difference in expressing pharmacological effects of ginseng by intestinal microfora between Koreans, metabolic activities of ginseng, ginsenoside Rb₁ and Rg₁ by 100 fecal specimens were measured. The β-glucosidase activity for p-nitrophenyl-β-D-glucopyranoside was 0 to 0.42 mmol/min/mg and its average activity (mean±SD) was 0.10±0.07 mmol/min/mg. The metabolic activities of ginsenosides Rb₁ and Rg₁ were 0.01 to 0.42 and 0.01 to 0.38 pmol/min/mg, respectively. Their average activities were 0.25±0.08 and 0.15±0.09 pmol/min/mg, respectively. The compound K-forming activities from ginsenoside Rb₁ and ginseng extract were 0 to 0.11 and 0 to 0.02 pmol/min/mg, respectively. Their average compound K-forming activities were 0.24±0.09 pmol/min/ mg and 2.14±3.66 fmol/min/mg, respectively. These activities all were not different between males and females, or between ages. Although compound K-forming activity from the aqueous extract of ginseng was low compared to that from ginenoside Rb₁, their profles were similar to those of isolated compounds. Based on these fndings, we believe that the intestinal bacterial metabolic activities of ginseng components are variable in individuals and may be used as selection markers for responders to ginseng.