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酸枣仁抗氧化成分提取及其活性 总被引:2,自引:0,他引:2
通过活性跟踪测试,结合正交实验与响应面设计Box-Benhnken实验,对不同提取方法、提取溶剂、提取次数等条件下的酸枣仁提取物进行了体外抗氧化活性测定,以提取率、总还原力、羟自由基清除率、DPPH清除率和总抗氧化能力评价了酸枣仁的抗氧化活性. 结果表明,提取物抗氧化活性最优的提取条件为:76.5℃下回流提取1次、提取时间4.5 h、提取溶剂60%乙醇含量为59.1%(j)、液固比为10 mL/g. 由提取物的紫外及红外图谱判断酸枣仁中抗氧化活性成分为黄酮类物质. 相似文献
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为了研究黄檗乙醇提取物的抗氧化活性及其与主要活性成分小檗碱含量的关系,为黄檗资源的开发利用提供参考和理论基础。采用了乙醇超声法从黄檗皮中提取出主要活性物质小檗碱提取物,利用高效液相色谱进行小檗碱含量检测,通过1,1-二苯基-2-三硝基苯肼(DPPH)、邻苯三酚自氧化法、Fe+还原法(FRAP)三种抗氧化模型对黄檗的乙醇提取物进行抗氧化活性评价,同时分析抗氧化活性与提取物中小檗碱含量的关系。结果表明:黄檗皮中小檗碱提取物对DPPH自由基和超氧化物阴离子自由基的清除作用及对亚铁离子的还原能力均呈正相关,当提取物中小檗碱含量为最大值0.134 mg/g时,对DPPH自由基和超氧化物阴离子自由基的清除作用分别达到96%和60%以上,对亚铁离子还原的FRAP值达到0.8以上。表明了黄檗皮乙醇提取物在体外具有较好的抗氧化活性,并随小檗碱含量的增加而增强。 相似文献
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《广东化工》2018,(21)
目的建立黄酮类化合物的高效合成方法并对其抗氧化活性进行研究。方法以醛和邻羟基苯乙酮为原料,通过Claisen-Schmidt缩合反应和Algar-Flynn-Oyamada反应高效的合成黄酮类化合物;并以芦丁为对照,对其清除1,1-二苯基-2-三硝基苯肼(DPPH)自由基的能力进行研究。结果得到七个全新的黄酮类化合物(3a~3g),以甲醇为反应溶剂,在碱性条件下反应4 h为最优反应条件,均进行了1H NMR,13C NMR和MS表征;经体外抗氧化活性实验测定,结果显示化合物3f在浓度为1.0 mg·mL-1时,DPPH自由基清除率达到29.5%,表现出抗氧化能力。结论该工艺可高效的合成黄酮类化合物,且该类化合物具有优异的抗氧化活性。 相似文献
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为探究虎杖根6种不同溶剂提取物的抗氧化活性,利用1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除法、2,2-二氮-双(3-乙基苯并噻唑-6-磺酸)铵盐(ABTS)自由基清除法和总还原力检测法对6种不同溶剂虎杖根提取物进行抗氧化能力评价。选用抗氧化活性较强的95%乙醇提取物进行细胞层面内源性抗氧化能力的研究,评价其对抗氧化基因Nrf2、SOD、CAT、HO-1的调控作用。结果表明,相较于其他5种提取物,95%乙醇提取物的抗氧化能力最强且具有最高的多酚含量。95%乙醇提取物可显著增加Nrf2、SOD、CAT、HO-1等抗氧化基因的表达。95%虎杖根乙醇提取物具有较好的抗氧化活性,具有开发成为天然抗氧化剂的潜力。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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塔设备改造选型的分析 总被引:2,自引:0,他引:2
就当前扩产增容中塔设备设计和改造时板式塔和填料塔的选型问题加以分析。在评述目前国内常用的几种塔板和新型填料之后,着重介绍一种新型塔板(导向梯形浮阀塔板)和一种新型填料(波环填料——乾隆帕克)。 相似文献
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