目的 研究牛蒡Arctium lappa根中咖啡酸类化学成分及其神经保护活性.方法 采用硅胶、C₁₈反相硅胶、Sephadex LH-20、AB-8大孔树脂柱色谱以及制备HPLC等方法对咖啡酸类化合物及类似物进行分离纯化,通过波谱学方法鉴定其结构,并采用MTT法对分离得到的化合物进行抗谷氨酸诱导神经母细胞瘤SH-SY5Y细胞株神经损伤的活性评价.结果 从牛蒡根55%乙醇提取物中分离得到8个咖啡酸类化合物,分别鉴定为1,5-O-二咖啡酰-3-O-(4-苹果酸甲酯)-奎宁酸(1)、3,5-二咖啡酰奎宁酸甲酯(2)、3,4-二咖啡酰奎宁酸甲酯(3)、4,5-二咖啡酰奎宁酸甲酯(4)、(2E)-1,4-dimethyl-2-[(4-hydroxyphenyl) methyl]-2-butenedioicacid(5)、绿原酸甲酯(6)、咖啡酸甲酯(7)、3,4,3',4'-tetrahydroxy-δ-truxinate(8),经活性测试发现此类化合物均具有较好的神经保护活性.结论 牛蒡根的抗谷氨酸诱导神经损伤的活性与其含有的咖啡酸类化合物有关;化合物1为新化合物,化合物5为新天然产物,化合物2～4、6、7为首次从该植物中分离得到,化合物8为首次从该属植物中分离得到.

Objective To investigate the caffeic acid compounds from the roots of Arctium lappa and their neuroprotective activity. Methods The compounds were isolated by column chromatography over silica gel, octadecylsilane (ODS) chemically bonded silica gel, Sephadex LH-20, and AB-8 macroporous resin coupled with preparative HPLC. Their structures were elucidated by spectroscopic analysis and their neuroprotective activity against glutamate-induced neurotoxicity was evaluated in SH-SY5Y cells by MTT assay. Results Eight caffeic acid compounds were isolated from the roots of A. lappa, which were identified as 1,5-O-dicaffeoyl-3-O-(4-malic acid methyl ester)-quinicacid (1), 3,5-O-dicaffeoyl-quinic acid methyl ester (2), 3,4-O-dicaffeoyl-quinic acid methylester (3), 4,5-O-dicaffeoyl-quinic acid methyl ester (4), (2E)-1,4-dimethyl-2-[(4-hydroxyphenyl)methyl]-2-butenedioicacid (5), chlorogenic acid methyl ester (6), caffeic acid mtheyl ester (7), and 3,4,3',4'-tetrahydroxy-δ-truxinate (8). In vitro, these compounds showed the neuroprotective activity against glutamate-induced neurotoxicity on different levels. Conclusion The neuroprotective activity of the roots in A. lappa against glutamate-induced neurotoxicity is related to the caffeic acid compounds. Compound 1 is a new compound; Compound 5 is a new natural compound; Compounds 2-4 and 6-7 are isolated from A. lappa for the first time; Compound 8 is isolated from the plants of Arctium L. for the first time.

国家科技重大专项资助项目(2014ZX09J14101-05C)