Study on excretion of pseudo-ginsenoside GQ

OBJECTIVE To determine the pseudo-ginsenoside GQ (PGQ) in rat bile, feces and urine, and to study on the excretion of pseudo-ginsenoside GQ. METHOD Reverse phase high-performance liquid chromatography (RP-HPLC) method with an evaporative light-scattering detector (ELSD) was performed on Diamonsil C18 column (4.6 mm x 250 mm, 5 microm), and the mobile phase was consisted of methanol-water (24: 7) with flow rate of 1.0 mL x min(-1). ELSD parameters were set as follows: nitrogen gas pressure 3.0 bar, drift tube temperature 50 degrees C. RESULT The method fulfilled all the standard requirements of precision, accuracy and linearity. The main way of excretion of PGQ in rat administrated through sublingual vein was at the bile. The bile excretion ratio of PGQ was 41.60%, and feces excretion ratio was 9.97%. Only trace amount of PGQ was excreted in urine. CONCLUSION Almost all unchanged PGQ was excreted in bile, feces and urine.