[Geo-authenticity evaluation of Sophorae Tonkinensis Radix et Rhizoma based on anti-inflammatory effect-constituents...

This study aimed to establish a method for the geo-authenticity evaluation of Shandougen(Sophorae Tonkinensis Radix et Rhizoma) based on the anti-inflammatory effect-constituents index(ECI). A quantitative fingerprint of Shandougen was developed by high performance liquid chromatography, and the content of six indicator constituents-oxymatrine, oxysophocarpine, matrine, sophocarpine, trifolirhizin, and maackiain-in 14 batches of samples collected from different geographical origins was determined. The anti-inflammatory potency of Shandougen samples from different geographical origins, as well as the half maximal inhibitory concentrations(IC_(50)) of the six individual indicator components, were measured by cyclooxygenase-2(COX-2) assay kits. On the basis of the IC_(50) value of each anti-inflammatory constituent, the weight coefficient for their anti-inflammatory potency was determined, and then the ECI values were calculated by integrating these weight coefficients with the content determination results. The fingerprint analysis results showed that a total of 13 common peaks were identified in 14 batches of Shandougen from different geographical origins, among which six characteristic peaks were identified as oxymatrine, oxysophocarpine, matrine, sophocarpine, trifolirhizin, and maackiain. The content determination results indicated that there were significant differences in the content of the six constituents among the 14 batches of samples. For example, the oxymatrine content in the sample S2 collected from Baise was 2.3 times of that in the sample S13 from Guizhou. The anti-inflammatory potency of the 14 batches of Shandougen ranged from 64.10 to 115.69 U·mL~(-1). Notably, the potency of samples from Guangxi was in the range of 73.94-115.69 U·mL~(-1), which was significantly higher than that of samples from other regions(64.10-86.39 U·mL~(-1)), suggesting that Shandougen from Guangxi possessed superior anti-inflammatory activity. The theoretically calculated ECI values exhibited a consistent trend with the anti-inflammatory potency. Specifically, the ECI of samples from Guangxi was 2.745-5.944, while that of samples from other regions was 2.477-3.569, further confirming the anti-inflammatory efficacy advantage of Shandougen from Guangxi. Correlation analysis results demonstrated that compared with the content of any single constituent, the ECI showed the optimal correlation with the anti-inflammatory potency of Shandougen(r=0.805, P<0.01), indicating that ECI was an accurate indicator for evaluating the anti-inflammatory efficacy of Shandougen from different geographical origins. In conclusion, this study successfully established a geo-authenticity evaluation method for Shandougen based on anti-inflammatory ECI. This method is applicable for the geo-authenticity evaluation of multi-batch Shandougen samples from different origins and provides a reference for the construction of geo-authenticity evaluation systems for other Chinese medicinal materials.