Determination of diosgenin in Asparagus officinalis byproduct by RP-HPLC.

[Objective] To establish a method for determining the content of diosgenin in Asparagus officinalis byproduct by RP-HPLC. [Methods] The diosgenin content was determined by RP-HPLC, and RP-HPLC conditions were: chromatographic column of SHIMADZU C18 column (4.6 mm×250 mm, 5 μm), mobile phase of methanol-water with volume ratio of 95∶5, flow rate of 0.8 ml/min, detection wavelength of 204 nm, column temperature of 30 ℃ and sampling volume of 20 μl. [Results] Diosgenin could be separated obviously from the interferential components in the sample. The calibration curve was linear in the range of 0.2 and 1.0 mg/ml with correlation coefficient of 0.999 7. RSD value of instrument precision and method repeatability was 0.27% and 0.81%, respectively. The average recovery of diosgenin was 99.1%. [Conclusion] RP-HPLC method was suitable for determining the content of diosgenin in Asparagus officinalis byproduct without any derivatization, determination of which was rapid, accurate and reproducible with good separation.