大叶锣的酚性成分及其体外抗氧化活性研究

Study on phenolic constituents and antioxidant activity of Didissandra sesquifolia C.B.Clarke

本文首次对大叶锣(Didissandra sesquifolia C.B.Clarke)全草的化学成分及其体外抗氧化活性进行了研究,通过多种色谱和波谱技术,分离并鉴定了15个酚类化合物,分别为对羟基苯乙醇(1)、香草酸(2)、6-hydroxyluteolin-7-O-glucuronide(3)、stachannin A(4)、野黄芩素(5)、calceolarioside E(6)、verbasoside(7)、calceolarioside A(8)、calceolarioside B(9)、plantainoside A(10)、isonuomioside A(11)、7-O-甲基黄芩素-6-O-葡萄糖苷(12)、鼠李柠檬素-3-O-β-D葡萄糖苷(13)、1,4-二羟基-2-羟甲基蒽醌(14)和1,4-二羟基-2-甲基蒽醌(15),以上所有化合物均为首次从漏斗苣苔属植物中分离得到。此外,还对大叶锣的化学成分及其各组分的DPPH、ABTS自由基清除能力和总还原能力(FRAP)进行了初步研究,结果显示化合物9、10的抗氧化活性(5.14±0.36、5.35±0.04 mmol VCE/g)接近抗坏血酸(5.68±0.10 mmol VCE/g),化合物6~11的总还原能力均大于FeSO4,显示出了良好的抗氧化活性,为其在天然抗氧化剂的开发以及药物先导化合物的筛选上奠定基础。

In this study,the chemical constituents and antioxidant activities of Didissandra sesquifolia C.B.Clarke were investigated for the first time.A total of 15 phenolic compounds were isolated and identified by a variety of chromatographic and spectroscopic techniques,including 4-hydroxyphenethyl alcohol(1),vanillic acid(2),6-hydroxyluteolin-7-O-glucuronide(3),stachanin A(4),scutellarein(5),calceolarioside E(6),verbasoside(7),calceolarioside A(8),calceolarioside B(9),plantainoside A(10),isonomioside A(11),scutellarein-6-O-glucoside-7-O-methylester(12),rhamnocitrin-3-O-β-D-glucosid(13),1,4-dihydroxy-2-hydroxymethyl-9,10-anthraquinone(14) and 1,4-dihydroxy-2-methylanthraquinone(15).All the compounds were isolated from the genus Didissandra plant for the first time.The in vitro antioxidant activities of the main chemical components and fractions were evaluated by DPPH,ABTS,and FRAP assays.And the results showed that the antioxidant activities of compounds 9,10(5.14±0.36,5.35±0.04 mmol VCE/g) were close to ascorbic acid(5.68±0.10 mmol VCE/g).In addition,the total reducing ability of compounds 6-11 was higher than that of FeSO4,which showed excellent antioxidant activity and laid the foundation for the development of natural antioxidants and the screening of drug lead compounds.