ABSTRACT
Objective::On the basis of previous research, to detect the changes of six main alkaloids in Gelsemium elegans rhizomes before and after being processed, so as to reveal its internal mechanism of processing. Method::The contents of gelsemine, humantenidine, koumine, gelsenicine, gelsevirine and humantenine in G. elegans rhizomes was determined simultaneously by HPLC, the content changes of these components before and after processing and its reasons were analyzed by cluster analysis and principal component analysis. The mobile phase was methanol (A)-0.1%formic acid aqueous solution (B) for gradient elution (0-10 min, 22%A; 10-20 min, 22%-30%A; 20-30 min, 30%-40%A). The flow rate was 1.0 mL·min-1. The detection wavelength was set at 254 nm, the injection volume was 10 μL, and the column temperature was 30 ℃. Result::Before processing, contents of the above six components in raw products were 1.444, 1.129, 3.590, 1.603, 2.376, 1.631 mg·g-1, after processing, the contents of these six components were 2.258, 0.343, 1.176, 0.115, 0.459, 0.281 mg·g-1, respectively. Gelsenicine, the most toxic ingredient of G. elegans rhizomes, decreased most significantly with a decreasing rate of 92.83%, while the less toxic ingredient, gelsemine, increased by 56.37%after processing. The contents of other four components in G. elegans rhizomes decreased to varying degrees after processing. The results of cluster analysis indicated that G. elegans rhizomes were clearly divided into two categories before and after processing. Principal component analysis showed that the first principal component before and after processing was changed from koumine to gelsemine. Conclusion::The degradation of toxic components and content changes of other components may be one of the intrinsic mechanism of toxicity attenuation and efficacy reservation of G. elegans rhizomes being processed.