【作者】 樊亚苏；

【导师】 何开跃；

【作者基本信息】 南京林业大学 ， 植物学， 2007， 硕士

【摘要】 用有机溶剂提取法对4年生的阔瓣含笑(Mechlia platypetala Hand.-Mazz)、乐昌含笑(Michelia chapensis Dandy)、金叶含笑(Michelia foveolata Merr.et Dandy)和深山含笑(Michelia maudiae Dunn)叶片的抗氧化物质进行提取,以颗粒度、提取温度和提取时间为考察因素,采用正交实验对提取工艺进行了优化研究,以获得最佳提取条件。用化学显色法、UV紫外吸收光谱和GC/MS对提取物成分进行了分析。并在体外研究了四种含笑乙醇提取物、四种含笑不同溶剂提取物的抗氧化活性以及乐昌含笑乙醇提取物与PA、PG、VC和柠檬酸的协同增效作用。主要结论如下:(1)通过正交试验优化出四种含笑抗氧化物质的最佳提取工艺为:颗粒度20目、提取温度90℃和提取时间18h。(2)从成分分析结果可知,四种含笑乙醇提取物中含有酚类化合物和黄酮类化合物。阔瓣含笑提取物中鉴定出42种化合物,主要成分为萜类化合物和醇类。乐昌含笑提取物中鉴定出42种化合物,主要成分为芳香族化合物和萜类化合物。金叶含笑提取物中鉴定出52种化合物,主要成分为芳香族化合物和醇类。深山含笑提取物中鉴定出21种化合物,中主要成分为芳香族化合物和萜类化合物。(3)以PA和PG为对比,从对自由基的清除作用、提取物的还原能力和对脂质过氧化的抑制作用三方面在体外评价了四种含笑乙醇提取物的抗氧化活性。结果表明:四种含笑乙醇提取物在各抗氧化体系中均表现出较强的抗氧化活性,其抗氧化活性随着浓度的增加而增大。在油脂体系中,四种含笑乙醇提取物对油脂的抗氧化系数(PF)在1～2之间,说明四种含笑乙醇提取物对大豆油、葵花籽油和猪油均有抗氧化作用。对四种含笑乙醇提取物的抗氧化活性进行了综合评价,其抗氧化活性大小依次为:乐昌含笑、阔瓣含笑、深山含笑和金叶含笑。(4)结果表明:四种含笑三种不同溶剂(乙醇、乙酸乙酯和石油醚)提取物中,除了阔瓣含笑、乐昌含笑和深山含笑的石油醚提取物在卵磷脂体系中对脂质过氧化无抑制作用外,其他提取物均有抗氧化作用,由各项指标综合评价得出,金叶含笑的石油醚提取物抗氧化活性最强,其他三种含笑的乙醇提取物抗氧化活性最强。由此,筛选出乙醇是最佳的提取溶剂。(5)在试验中发现PG、VC和柠檬酸对乐昌含笑乙醇提取物在各抗氧化体系中均有协同增效作用; PA在羟自由基、卵磷脂和油脂体系中对乐昌含笑乙醇提取有协同增效作用,而在超氧阴离子自由基和DPPH·自由基体系对乐昌含笑乙醇提取物无增效作用。更多还原

【Abstract】 The antioxidant substances of M.platypetala, M.chapensis, M.foveolata and M.maudiae of four years were extracted by organic solvent method. Granularity, extraction temperature and extraction time were selected as three factors to design the orthogonal experiment, and the optimum conditions of extraction were obtained.The components were analyzed by chemical colorimetric method, ultraviolet absorption spectrum and GC/MS. The antioxidant activitiy of ethanol extracts and different solvent extracts of Michelia of four species was studied in vitro, and the synergism of ethanol extract of M.chapensis with phytic acid, propyl gallate, ascorbic acid and citric acid was studied at the same time in the experiment. The main conclusions were as follows:(1)The optimum extraction conditions determined by orthogonal experiment were as follows: granularity 20 eyes, extraction temperature 90℃and extraction time 18 hours.(2)The results showed that the ethanol extracts of Mechlia of four speices contained phenolic compounds and flavonoids. 42 compounds in M.platypetala were indentified and the main components were terpeniods and alcohol. 42 compounds in M.chapensis were indentified and the main components were aromatic and terpenoids. 52 compounds in M.foveolata and the main components were aromatic and alcohol. 21 compounds in M.maudiae were indentified and the main components were aromatic and terpenoids.(3)The antioxidant activity of ethanol extracts of Mechlia of four species was evaluated in vitro by various antioxidant systems, including free radical scavenging, reducing power and lipid peroxidation inhibition, and antioxidant activitiy of ethanol extracts of Mechlia of four species was compared with standard antioxidants such as phytic acid (PA) and propyl gallate (PG)in all antioxidant systems. The researchs showed that the extracts have powerful antioxidant activity in all antioxidant systems, and the antioxidant activity increases with increasing the concentration of samples.The oxidation protection factor of the extracts was between 1 and 2 in edible oil systems. The results showed that the extracts have antioxidant activity to soybean oil, sunflower seed oil and lard.The antioxidant activity of extracts was comprehensive evaluated, and the order of antioxidant activity decreasing was M.chapensis, M.platypetala, M.maudiae and M.foveolata.(4) The results showed that the three solvent extracts of Mechlia of four species have antioxidant activity in all antioxidant systems except petroleum ether extracts of M.platypetala, M.chapensis and M.maudiae. All extraxts were comprehensive evaluated, and the result showed that petroleum ether extract of M.foveolata had the best antioxidant activity, but ethanol extracts of M.platypetal, M.chapensis and M.maudiae have the best antioxidant activity. Therefore, ethanol was choosen as the best extraction solvent. (5) propyl gallate,ascorbic acid and citric acid have synergism to the ethanol extracts of M.chapensis in all antioxidant systems. phytic acid had synergism to the ethanol extracts of M.chapensis in all antioxidant systems except superoxide anion free radical system and DPPH·free radical system.更多还原