四种花卉的化学成分及其抗氧化活性研究

【作者】 太志刚；

【导师】 丁中涛；

【作者基本信息】 云南大学 ， 有机化学， 2011， 博士

【摘要】 云南是花卉大省,很多花具有较高的药用和食用价值,系统研究云南的花卉资源具有重要意义。本文基于植物化学、分析化学和药物化学的研究方法和手段,对四种花卉进行了系统的研究：论文第二部分利用植物化学方法对药用花卉-唐菖蒲地上部分进行了系统的化学成分研究。第三部分采用多种抗氧化体系评价了三种食用花卉(白刺花、金雀花和绿萝花)的抗氧化活性,探讨了不同萃取部位的抗氧化能力及其变化规律；测定了其中的总酚、总黄酮等含量,探讨了它们与抗氧化活性间的相关性；对这三种花卉提取物的化学成分进行研究,并对所得到的酚类化合物进行了抗氧化活性测试和含量分析,综合分析了抗氧化活性物质对抗氧化能力的贡献；另外还对白刺花、金雀花和绿萝花三种花卉的抗氧化活性进行了综合比较。论文还总结归纳了抗氧化活性研究进展。本研究为这四种特色花卉资源的开发和综合利用提供了理论依据,有利于促进云南省特色花卉的深入开发和利用。第一章：参考国内外发表的98篇文献,从自由基的产生及危害、抗氧化活性筛选方法、天然抗氧化剂分类及其相应机理三个方面综述了抗氧化研究进展。第二章：采用植物化学方法对鸢尾科的唐菖蒲(Gladiolus gandavensis)化学成分进行了研究。从其乙醇提取物中分离鉴定了32个化合物,其中有9个新的齐墩果型三萜皂甙(1-9),其结构特点是C-29位甲基被羟基或者糖苷所取代,这类结构不多见。第三章：以化学成分为基础,以抗氧化活性为核心,采用植物化学、分析化学、药物化学的研究方法和手段,对豆科槐属白刺花(Sophora viciifolia)、豆科锦鸡儿属金雀花(Caragana sinica)和天南星科绿萝花(Scindapsus aureus)进行了系统的研究。1.分别利用5种不同机理的模型(ABTS, FRAP, DPPH,还原力和脂质过氧化抑制力)对白刺花提取物及各萃取部分进行了抗氧化研究。研究结果表明乙酸乙酯部分的抗氧化能力相对其他部分较强。相关性分析揭示抗氧化活性能力归功于其中大量的黄酮类化合物。进一步追踪其化学成分,从中分离得到16个化合物,其中luteolin(4)和quercetin (3)清除DPPH自由基的能力最强。HPLC分析表明白刺花中的luteolin(4)含量高达5.56mg/g样品,这表明luteolin(4)可能代表了白刺花花蕾的抗氧化活性。2.利用羟自由基,DPPH, FRAP,β-胡萝卜素和脂质过氧化抑制能力等抗氧化模型对食用花卉--金雀花的提取物及其乙酸乙酯,正丁醇,石油醚和水等萃取部分进行了研究,各部分抗氧化物质含量测定表明乙酸乙酯部分的总酚和总黄酮含量最高,抗氧化活性最强,相关性分析揭示抗氧化活性与其中的黄酮类化合物相关。对其化学成分进行了研究,分离鉴定了23个化合物,这些化合物均为首次从金雀花花蕾中分离得到。HPLC分析结果表明quercetin-3’-O-methyl-3-O-α-L-rhamnopyranosyl(1→6)-β-D-glucopyranoside(4)和rutin(3)是金雀花中主要的黄酮类化合物,含量分别是3.94mg/g样品1.20 mg/g样品。3.采用不同模型对绿萝花的提取物进行抗氧活性研究。研究表明乙酸乙酯部分的抗氧化能力最高,但相关性分析表明乙酸乙酯部分抗氧化活性与黄酮化合物关联不强。对其化学成分进行了研究,首次从中分离得到26个化合物。在分离得到的化合物中,(-)-epi-catechin (8),3-(3,4-dihydroxyphenyl)-2-propenoic acid methyl ester(14),3-(3,4-dihydroxyphenyl)-E-acrylic acid 1-(3,4-dihydroxyphenyl)-2- methoxy-carbonylethy ester (19), catechol (20)和gallic acid (21)五个酚类化合物(特别是其中的没食子酸(21))可能代表了绿萝花的抗氧化活性。4.通过相关的抗氧化模型和抗氧化物含量的测定,比较白刺花,金雀花和绿萝花的抗氧化活性,它们抗氧化活性能力大小为,白刺花>金雀花>绿萝花。几种抗氧化模型之间相关性比较表明,把FRAP和鼠肝鼠肾脂质过氧化抑制实验结合起来能比较准确的反映白刺花、金雀花和绿萝花的抗氧化活性。更多还原

【Abstract】 Yunnan Province is famous for its flowers, and some of flowers can be used as food or medicine. It is very meaningful to carry out a thorough study of the flowers in Yunnan. Four kinds of flowers, Gladiolus gandavensis, Sophora viciifolia, Caragana sinica and Scindapsus aureus were chosen as the research objects in the current study for their high value in the food and medical fields. Firstly, on the basis of phytochemistry theory and method, the chemical constituents of the aerial part of Gladiolus gandavensis were investigated, and 9 new compounds were obtained. In the second part, three flowers(Sophora viciifolia, Caragana sinica and Scindapsus aureus) were studied to evaluate their antioxidant properties and chemical constituents, respectively. And the chemical compounds which might play the important role for the strong antioxidant activity of these flower, were isolated. This study suggests that these three flowers can provide valuable functional ingredients and can be used for the prevention of diseases related to various oxidant by-products of human metabolism. This thesis includes three chapters:In Chapter 1, the research progress of antioxidant activity was reviewed from the following three aspects:(1) Production and harm of free radicals; (2) Antioxidant activity screening methods; (3) Different types and structure-activity relationship of natural antioxidant.In the chapter 2, the study on the chemical constituents of Gladiolus gandavensis was carried out. Thirty-two compounds, including nine new triterpene saponins were isolated and elucidated from ethanol extract of this plant. These new oleanane-type triterpene saponins glycosidated at C-29 were not obtained frequently.In the chapter 3, based on their chemical constituents, the antioxidant activities of Sophora viciifolia, Caragana sinica and Scindapsus aureus were studied systematically.Firstly, the antioxidant capacities of extracts of Sophora viciifolia flower were evaluated by several test methods (ABTS, DPPH, reducing power, FRAP and inhibition of lipid peroxidant models) for the first time. And the ethyl acetate fraction showed the highest antioxidant activity. Correlation analysis revealed that the flavonoids might be mostly responsible for the antioxidant activity of this flower. In addition, sixteen compounds were isolated from this flower. Luteolin (4) exhibiting good DPPH radical scavenging activity was abundant in this flower (5.56 mg/g dry sample), which implied an important role of luteolin for the antioxidant capacity of Sophora viciifolia flowers. Secondly, twenty-three compounds were isolated from Caragana sinica flower for the first time. Moreover, the antioxidant activities of extracts of this flower were evaluated through several chemical systems (FRAP, DPPH, hydroxyl radical,β-carotene bleaching methods and inhibition of lipid peroxidant models). Ethyl acetate fraction was proved to be the most active antioxidant extract of this flower. And the flavonoids in this flower might contribute to the good antioxidant activity of this flower. The HPLC analysis showed that the compounds of quercetin-3’-O-methyl-3-O-α-L-rhamnopyranos-yl (1→6)-β-D-glucopyranoside (4) and rutin (3), turned out to be the major flavonoids with the concentration of 3.94 mg/g sample and 1.20 mg/g sample, respectively.Thirdly, twenty-six compounds were isolated from Scindapsus aureus flower for the first time. According to the results determined by several in vitro antioxidant models, the ethyl acetate fraction was proved to be the most efficient for antioxidant activity. However, correlation analysis showed less correlation between antioxidant activity and flavonoids. Five powerful antioxidants (phenolics), such as (-)-epi-catechin (8),3-(3, 4-dihydroxyphenyl)-2-propenoic acid methyl ester (14),3-(3,4-dihydroxyphenyl)-E-acrylic acid 1-(3,4- dihydroxyphenyl)-2-methoxycarbonylethy ester (19), catechol (20) and gallic acid (21) were found in the ethyl acetate fraction, suggesting an important role of these compounds for the antioxidant capacity of Scindapsus aureus flower.Fourthly, the comparison of antioxidant activities and antioxidant contents of these three flowers let to the antioxidant capacity order of Sophora viciifolia>Caragana sinica> Scindapsus aureus. And the significant correlations between FRAP and inhibition of lipid peroxidant assay shuggested that the combination of these two methods can be used to quantify antioxidant capacities of these three flowers(Sophora viciifolia, Caragana sinica and Scindapsus aureus) accurately.更多还原