为了研究大蓟(Cirsium japonicum)紫外光谱的显著鉴别特征，以快速、准确地鉴别正品大蓟，采用多溶剂紫外光谱法分析福建省不同地区的自采大蓟和市售18批不同厂家商品大蓟在无水乙醇、氯仿及石油醚溶剂中紫外特征差异，并采用主峰值(含肩峰值)及主谷值的均值加方差归纳比较特征。结果表明，自采大蓟在无水乙醇溶剂中表现为“谷—峰—谷—峰”，即在273±3 nm、326±2 nm处的峰值和250±2 nm、298±1 nm处的谷值具有显著鉴别意义；在氯仿溶剂中，表现为“峰—谷—峰”，即在245±3 nm、273±4 nm处的峰值和260±3 nm处的谷值具有显著鉴别意义；在石油醚溶剂中表现为“肩峰—谷—峰”，即在233±3 nm处的肩峰、265±5 nm处的峰值和257±5 nm处的谷值具有显著鉴别意义。紫外光谱的峰谷特征可用于大蓟鉴别。

The identifiable characteristics of Cirsium japonicum was studied by UV spectrum for a quick and accurate identification. Multi-solvent ultraviolet spectroscopy was used to analyze the difference of ultraviolet characteristics between self-collected C. japonicum from different areas of Fujian province and 18 batches of commercial C. japonicum from different manufacturers in anhydrous ethanol, chloroform and petroleum ether solvents, and the characteristics by mean plus variance of the main peak value (shoulder peak value) and the mean valley value were induced. The self-collected C. japonicum shows ‘valley-peak-valley-peak’ in anhydrous ethanol solvent: the peak value at 273±3 nm, 326±2 nm and the valley value at 250±2 nm, 298±1 nm, which have significant differential significance; In chloroform solvent, it shows ‘peak-valley-peak’: the peak value at 245± nm, 273±4 nm and the valley value at 260±3 nm, which have significant discrimination significance; In petroleum ether solvent, it shows ‘shoulder peak-valley-peak’: the peak value at 233±3 nm, 265±5 nm and the valley value at 257±5 nm, which have significant discrimination significance. The peak and valley characteristic induction of UV spectrum can be used to identify C. japonicum.