Objective: To study the determination of conduritol A in the flower of Gymnema sylvestre. Method: The best extraction technology for conduritol A was studied through orthogonal experiment; HPLC was adopted to determine the content of conduritol A.The separation was performed on a Thermo NH2 column(4.6 mm×250 mm

5 μm); acetonitrile:water(90: 10)was used as mobile phase; the flow rate was 1.0 mL·min-1; the detection wave was set at 207 nm and the column temperature was kept at 30 ℃. Result: The best extraction technology of conduritol A was ultrasonic extraction in 50% methanol of 150 times for 50 min.The liner range of conduritol A was 0.400 4-20.02 μg(r=0.999 7); the average recovery rate was 98.98%

RSD was 1.15%(n=6). Conclusion: The method was accurate

quick

sensitive with good reproducibility

it could be used as the quality control method of the flower of Gymnema sylvestre.