Quantitive analysis of gleditsia saponins in the fruits of Gleditsia sinensis Lam. by high performance liquid chromatography.

A high performance liquid chromatography method was developed for simultaneous quantification of 29 ingredients occurring as a very complex mixture in the gleditsia fruits. The analysis was performed on an ODS-2 Hypersil column (250 mm × 4.6 mm, 5 μm) with a binary gradient mobile phase of water and acetonitrile both containing 0.1% acetic acid. The method was validated in terms of linearity, sensitivity, stability, precision, and accuracy. It was found that this method had linearity with R² at 0.99889-0.99997 in the test range of 1.0-24.0 μg. The limit of detection (LOD) and limit of quantification (LOQ) for 16 tested reference saponins were 0.24-0.39 μg and 1.0-1.2 μg, respectively. The relative standard deviations (RSDs %) for intra-day and inter-day repeatability were not more than 3.11% and 4.02%, respectively. The analyzed samples were stable for at least 48 h. The spike recoveries for eight analyzed saponins were 99.68-102.17%. The established HPLC analytic method was successfully used to determine the concentrations of 29 compounds including 19 gleditsia saponins and ten unidentified ingredients in eight commercial gleditsia fruits from different sources. The results from this study suggested that this newly developed HPLC method could be used for qualitative and quantitative analysis of the saponins in the gleditsia fruits and the gleditsia extracts that used for animal study and other purpose.