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金银花花茎中黄酮的提取及抗氧化性的研究 总被引:8,自引:0,他引:8
李志洲 《宝鸡文理学院学报(自然科学版)》2006,26(2):131-134
目的对陕南地产金银花花茎中黄酮类化合物进行提取及抗氧化性研究。方法采用正交实验法并利用超声波确定黄酮类化合物的提取最佳条件;采用烘箱储藏法测定抗氧化性;采用H2O2/Fe2 体系法测定样品对.OH的清除作用;采用AP-TEMED体系法测定样品对O2-清除作用。结果花茎中黄酮类化合物的最佳提取条件为20℃,6 h,75%的乙醇,料液比为1∶30;花茎中黄酮类化合物对猪油的氧化具有明显的抑制作用;对.OH的清除达50.22%;对O2-清除达17.28%。结论超声波提取效果明显,提取率可达2.34%;花茎中黄酮类提取物有明显的抗氧化性,对O2-、.OH自由基的消除有明显效果。 相似文献
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利用乙醇为溶剂提取桂花中总黄酮类物质.通过单因素实验和正交试验确定桂花总黄酮最佳提取工艺条件,并对桂花总黄酮体外抗氧化性能进行系统评价.得出以乙醇为溶剂提取桂花中总黄酮最佳工艺条件为:乙醇体积分数60%,提取功率360 W,料液比1∶35,浸提时间2 min,在此条件下总黄酮得率可达18.18%;体外抗氧化性能研究结果表明,桂花总黄酮具备较好抗氧化活性,在相同的加入量下桂花总黄酮对DPPH自由基清除率明显优于BHT,低于Vc. 相似文献
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幸宏伟 《重庆工商大学学报(自然科学版)》2006,23(2):150-153
研究了玫瑰花中抗氧化物质提取物对油脂类的抗氧化性。结果表明:玫瑰花中的抗氧化物质对猪油有明显的抗氧化作用,且抗氧化提取物的添加量在试验剂量范围内与其抗氧化性呈正相关;当玫瑰花中提取物添加量为猪油样的0.05%时,其抗氧化效果与0.02%VC相当,且玫瑰花中抗氧化物质与VC、VE、柠檬酸有较好的协同作用,尤其在与VC和VE混合时有最好的协同作用。 相似文献
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杜仲黄酮的提取及抗氧化活性研究 总被引:11,自引:1,他引:10
采用正交试验法研究了杜仲黄酮的最佳提取工艺条件,以猪油为底物,采用碘-硫代硫酸钠滴定法测定了杜仲黄酮对猪油的抗氧化活性及与有机酸的协同效应.结果表明:杜仲黄酮的最佳提取工艺条件为用质量分数为70%乙醇、料液比(g∶mL)为1∶10、80℃条件下提取3次、每次回流2 0h.杜仲黄酮对猪油具有明显的抗氧化活性,部分有机酸对其具有一定的增效作用,添加质量分数为0 30%杜仲黄酮可使猪油在20℃下的货架寿命由2 5个月延长至8 1个月. 相似文献
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资木瓜乙醇提取物的体外抗氧化活性研究 总被引:7,自引:0,他引:7
目的:对资木瓜乙醇提取物进行体外抗氧化活性研究.方法:以65%乙醇为溶剂加热回流提取资木瓜,旋转蒸发浓缩得资木瓜乙醇提取物(CSF),通过猪油体系(POV)、DPPH*法和Fe3 还原力测定实验对其进行体外抗氧化活性评价.结果:与对照组比较,资木瓜乙醇提取物能使猪油的过氧化值(POV值)降低,且随提取物浓度升高其降低POV值的能力增强,所选取的药物浓度较Vc(0.8mg/mL)强,但量效关系不明显;乙醇提取物具明显清除DPPH*自由基作用,随提取物浓度增加其清除率增加,当浓度为6mg/mL时清除率达到近80%;同时提取物对铁离子的还原能力亦较强,与提取物浓度呈正相关性.结论:资木瓜乙醇提取物具有较强的抗氧化活性. 相似文献
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用超声提取法分别对楠竹叶中黄酮类化合物的提取条件进行了研究,通过正交实验得出最佳条件:乙醇体积分数70%、料液比1:10(g/m L)、提取时间20 min,提取4次,总黄酮得率达到5.709%,相比传统的蒸馏法和索氏提取法(提取率3%)提取效率高,所需时间短,耗费溶剂量少.此外还研究了楠竹叶黄酮提取物对羟自由基和DPPH自由基的抗氧化能力,发现均具有较强的抑制作用. 相似文献
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将甜荞、苦荞粉碎后乙醇浸提法提取黄酮类化合物,其黄酮粗提物的得率分别为1.39%和2.76%,粗提物中黄酮含量分别为0.589%和3.22%.以BHT和Vc为阳性对照,研究两种荞麦黄酮粗提物对植物油和动物油的抗氧化效果.结果表明,两种荞麦黄酮粗提物具有显著的抗氧化性能,其中苦荞黄酮粗提物在两种油脂中的抗氧化性高于BHT和Vc. 相似文献
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香辛料有机溶剂提取物对油脂的抗氧化性能 总被引:5,自引:0,他引:5
研究了6种香辛料的不同有机溶剂提取物对猪油和花生油的抗氧化能力,发现这些提取物猪油的花生油均有一定的抗氧化作用,但效果差异较大,其中生姜提取物的效果最佳,相当于1.5g生姜干粉的甲醇,乙酸乙酯等的提取物对猪油,花生油的抗氧化效果均优于添加质量分数为0.005%的BHT(二丁基羟基甲苯)与DLTP/(硫代二丙酸二月桂酯),此外,不同极好的有机溶剂所提取的香辛料抗氧化组分,其抗氧化效果有明显的不同,甲 相似文献
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通过测定过氧化值(POV值),考查蜂胶乙醇提取物对猪油、菜籽油、花生油、大豆油4种油样的抗氧化效果,结果表明:蜂胶乙醇提取物对于以上4种油样都具有抗氧化的作用,添加0.5%蜂胶乙醇提取物的抗氧化能力是添加0.5%维生素E的2~3倍. 相似文献
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Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness. 相似文献
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Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly. 相似文献
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理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。 相似文献
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As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death. 相似文献
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Miao Maosheng 《华南师范大学学报(自然科学版)》2014,(6)
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula- 相似文献
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Yang Weitao 《华南师范大学学报(自然科学版)》2014,46(6):137-138
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re- 相似文献
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Bernard Kirtman 《华南师范大学学报(自然科学版)》2014,(6)
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that 相似文献
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《上海师范大学学报(自然科学版)》2014,(5):550
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with 相似文献
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《吉林大学学报(理学版)》2014,(5):1105
<正>"Journal of Jilin University(Science Edition)"is a comprehensive academic journal in the fields of science sponsored by Jilin University and administrated by the Ministry of Education of the Peoples Republic of China.The journal started publication in 1955.The original name at starting publication was"Journal of Natural Science of Northeast People University",which was changed into"Acta Scientiarum Naturalium Universitatis Jilinensis"in 1958 owing to the name change of the university.The present journal name has 相似文献