蒺藜果实化学成分及其抗氧化活性研究

目的 研究蒺藜Tribulus terrester果实的化学成分及其抗氧化活性。方法 综合利用硅胶柱色谱、Sephadex LH-20凝胶柱色谱等分离手段进行分离纯化；结合NMR、MS、IR、UV等波谱学技术来鉴定化合物的结构；通过DPPH法、ABTS法以及羟基自由基清除方法测定化合物的抗氧化活性。结果 从蒺藜果实75%甲醇提取物中分离鉴定了10个化合物，分别为(E)-4-hydroxy-N-(3-(4-hydroxy-3-methoxyphenyl)acryloyl)benzamide(1)、蒺藜酰胺（2）、海柯皂苷元（3）、25R-螺甾-4-烯-3,12-二酮（4）、槲皮素（5）、3,4’-二羟基-3’-甲氧基苯丙酮（6）、对羟基苯甲酸（7）、(9Z,11E)-13-hydroxy-9,11-octadecadienoic acid(8)、(8E,12Z)-10-hydroxy-8,12-octadecadienoic acid(9)、肉豆蔻酸（10），其中化合物1～6对DPPH、ABTS自由基以及羟基自由基均有较显著的活性，并且化合物5清除ABTS自由基和羟基自由基半数抑制浓度（...

Chemical constituents from fruits of Tribulus terrestrer and their antioxidant activity

Objective To investigate the chemical constituents from fruits of Tribulus terrestrer and their antioxidant activity. Methods The compounds were isolated and purified by silica gels column chromatography and Sephadex LH-20 column chromatography. Their structures were identified based on NMR, MS, IR, UV and other spectroscopic techniques. Their antioxidant activity were evaluated by scavenging capacity on DPPH, ABTS and ·OH radicals. Results Ten compounds were isolated from 75% methanol extract of the fruits of T. terrestrer and identified as (E)-4-hydroxy-N-(3-(4-hydroxy-3-methoxyphenyl) acryloyl)benzamide (1), tribulusamide (2), hecogenin (3), 25R-spirostan-4-ene-3,12-dione (4), quercetin (5), 3,4''-dihydroxy-3''-methoxyphenylacetone (6), p-hydroxybenzoic acid (7), (9Z,11E)-13-hydroxy-9,11-octadecadienoic acid (8), (8E,12Z)-10-hydroxy-8,12-octadecadienoic acid (9), and myristic acid (10). Compounds 1-6 had the stronger DPPH, ABTS and OH radicals scavenging abilities and compound 5 showed significant abilities with IC₅₀ values of 0.011 and 0.320 mmol/L. The IC₅₀ values were almost consistent with that of the V_C positive control group. Conclusion Compound 1 is a new compound, named tribulusimide D. Compounds 6-10 are isolated from fruits of Tribulus for the first time and also from the fruit of Tribulus terrestris for the first time. The antioxidant activity experiment showed that compounds 1-6 exhibited significant scavenging capacity.