Simultaneous quantitative analysis of nine triterpenoid saponins for the quality control of Stauntonia obovatifoliola Hayata subsp. intermedia stems

Stauntonia obovatifoliola Hayata subsp. intermedia is used in China to treat rheumatic arthralgia, hernia pain, and traumatic pain. An accurate and reliable method based on high-performance liquid chromatography with diode array detection has been developed and validated for the quantitative determination of nine triterpenoid saponins in this herb. By using a Kromasil 100-5 C18 column (250 mm × 4.6 mm, 5 μm), nine analytes were separated by gradient elution over a running time of 45.0 min. All standard calibration curves demonstrated satisfactory linearity (R(2) ≥ 0.9995) within a relatively wide range. The precision was evaluated by intra- and interday tests, which revealed relative standard deviation values within the ranges of 0.20-2.83 and 0.51-2.79%, respectively. The recoveries for the nine target compounds were between 84.6 and 103% with relative standard deviation values less than 2.67%. The samples were also analyzed on a linear trap quadrupole Orbitrap Velos Pro mass spectrometer equipped with an electrospray ionization source in negative mode to confirm the quantification results. In conclusion, the present high-performance liquid chromatography with diode array detection method could serve as an accurate and reliable method for the quality evaluation of Stauntonia obovatifoliola Hayata subsp. intermedia stems.