广藿香的抗补体活性成分

Anti-complementary constituents of Pogostemon cablin

采用硅胶、Sephadex LH-20等柱色谱方法对广藿香进行抗补体活性导向分离与鉴定,从乙酸乙酯部位和正丁醇部位共分离鉴定了15个黄酮、1个三萜和2个酚酸类成分,包括5-羟基-3,7,3',4'-四甲氧基黄酮(1)、5-羟基-7,3',4'-三甲氧基-二氢黄酮(2)、5,4'-二羟基-3,7,3'-三甲氧基黄酮(3)、5-羟基-3,7,4'-三甲氧基黄酮(4)、5,4'-二羟基-7,3'-二甲氧基黄酮(5)、木犀草素(6)、槲皮素-7,3',4'-三甲醚(7)、岳桦素(8)、3,5,7-三羟基-3',4'-二甲氧基黄酮(9)、槲皮素(10)、芹菜素(11)、山柰酚(12)、5-羟基-7,3',4'-三甲氧基黄酮(13)、山柰酚-7-O-β-D-葡萄糖苷(14)、山柰酚-3-O-β-D-葡萄糖苷-7-O-α-L-鼠李糖苷(15)、齐墩果酸(16)、香草酸(17)、对甲基苄醇(18),其中化合物5,7,8,12～15,18均为首次从唇形科刺蕊草属植物中分离得到。对所得单体化合物进行经典和旁路途径的体外抗补体活性测定,并利用补体缺失血清鉴定活性最强化合物的抗补体作用靶点,结果表明,化合物3,7,10,12,16对经典和旁路途径的补体激活均有抑制作用(CH500.072～1.08 g.L-1,AP500.39～0.49 g.L-1),而化合物5,6仅对经典途径有抑制活性;活性最强的槲皮素-7,3',4'-三甲醚(7)作用于补体系统的C1q,C2,C5和C9组分,值得深入研究。

Guided by anti-complementary activity, silica gel, Sephadex LH-20 and reversed-phase column chromatographies were used for fractionation and isolation of the ethyl acetate and n-butanol solnhle fractions of Pogostemon cablin. Eighteen compounds were obtained, including 15 flavonoids ： 5-hydroxy-3,7,3′,4′-tetramethoxyflavone （ 1 ）, 5-hydroxy-7,3′, 4′-trimethoxyflavanone （ 2 ）, 5,4′-dihydroxy-3,7,3′-trimethoxyflavone （3）, 5-hydroxy-3,7,4′-trimethoxyflavone （4）, 5,4′-dihydroxy-7,3′-dimethoxyflavone （5）, lnteolin （6）, quercetin-7,3′, 4′-trimethyl ether （ 7 ）, ermanine （ 8 ）, 3,5,7- trihydroxy-3′, 4′-dimethoxyflavone （ 9 ）, quercetin （ 10）, apigenin （ U ）, kaempferol （ 12）, 5-hydroxy-7,3′ ,4′-trimethoxyflavone （ 13）, kaempferol-7-O-β-D-glucopyranoside （14） and kaempferol-3-O-β-D-glucopyranoside-7-O-α-L-rhamnoside （15） ; one triterpenoid ： oleanic acid （16） ; and 2 phenolic acids ： vanillic acid （17） and benzylalcohol （18）. The isolation of 5, 7, 8, 12-15 and 18 from the Pogostemon genus is reported for the first time. All isolates were evaluated for their in vitro anti-complementary activities on the classical pathway and alternative pathway. And the targets of the most potent constituent in complement activation cascade were identified using complement-depleted sera. Compounds 3, 7, 10, 12 and 16 exhibited anti-complementary activities toward the classical pathway and alternative pathway （ CH50 0. 072-1.08 g . L-1, APs0 0. 39-0. 49 g . L-1 ）, while 5 and 6 showed inhibitory effect on the classical pathway only. Mechanism study indicated that 7 inter- acted with C1q, C2, C5 and C9 components.