贵州锥叶的化学成分及其酪氨酸酶抑制活性研究

Chemical constituents from leaves of Castanopsis kweichowensis and its tyrosinase inhibitory activities

目的对贵州锥Castanopsis kweichowensis叶的化学成分进行研究,并探究其对酪氨酸酶活性的影响。方法采用Sephadex LH-20、Chromatorex C_(18)、Diaion HP20SS、MCI gel CHP 20P等柱色谱分离技术对贵州锥叶提取物进行分离纯化,根据NMR、UV、MS以及IR等波谱技术对化合物进行结构鉴定。采用酪氨酸酶多巴速率氧化法测定化合物对酪氨酸酶的抑制作用。结果从贵州锥叶80%甲醇提取物中共分离得到18个化合物,分别鉴定为(4S)-α-松油醇-7-O-β-D-(6'-O-没食子酰基)葡萄糖苷(1)、没食子酸(2)、没食子酸甲酯(3)、2,5-二羟基苯甲酸(4)、原儿茶酸(5)、鞣花酸(6)、4-O-α-L-鼠李糖基-鞣花酸(7)、6-O-没食子酰基葡萄糖苷(8)、6-O-没食子酰基熊果苷(9)、4-羟基-2-甲氧基苯酚-1-O-β-D-(6'-O-没食子酰基)葡萄糖苷(10)、绿原酸(11)、芦丁(12)、macropteranthol(13)、28-β-D-glucopyranosyl-2α,3β,19α-23-trihydroxyolean-12-ene-24,28-dioic acid(14)、(7S,8R,7'R,8'S)-icariol A2-9-O-β-xylopyranoside(15)、(+)-isolariciresinol-3α-O-β-D-glucopyranoside(16)、transtorine(17)、蔗糖(18)。化合物2对酪氨酸酶抑制活性的半数抑制浓度(median inhibition concentration,IC50)值为(6.05±0.27)mmol/L。结论所有化合物均为首次从贵州锥中分离得到,其中化合物1为新化合物,命名为贵州锥苷A。化合物2具有较好的酪氨酸酶抑制活性。

Objective To investigate the chemical constituents from the leaves of Castanopsis kweichowensis and its tyrosinase activities.Methods The extract of leaves of C.kweichowensis was isolated and purified by column chromatographic separation techniques such as sephadex LH-20,Chromatorex C_(18),Diaion HP20SS,MCI gel CHP 20P.The structures of the compounds were identified by spectroscopic techniques such as NMR,UV,MS,and IR.The inhibitory effect of the compounda on tyrosinase was determined by tyrosinase dopa rate oxidation method.Results Eighteen compounds were isolated and identified as(4S)-α-terpineol-7-O-β-D-(6'-O-galloyl)glucopyranoside(1),gallic acid(2),gallic acid methlyl ester(3),2,5-dihydmxybenzoic acid(4),protocatechuic acid(5),ellagic acid(6),4-O-α-L-rhamnopyranosyl-ellagic acid(7),6-O-gallicacid-glucoside(8),6-O-galoylarbutin(9),4-hydroxy-2-methoxyphenol-1-O-β-D-(6'-O-galloyl)glucopyranoeide(10),chlorogenic acid(11),rutin(12),macropteranthol(13),28-β-D-glucopyranosyl-2α,3β,19α-23-trihy-droxyolean-12-ene-24,28-dioic acid(14),(7S,8R,7'R,8'S)-icariol A2-9-O-β-xylopyranoside(15),(+)-isolariciresinol-3α-O-β-D-glucopyranoside(16),transtorine(17),sucrose(18).Compound 2 possessed better tyrosinase inhibitory activity with IC50 of(6.05±0.27)mmol/L.Conclusion All the compounds are isolated from the leaves of C.kweichowensis for the first time,among which compound 1 is a new phenol glucoside named kweichowensin A.Compound 2 shows better tyrosinase inhibitory activity.