黄酮化合物的反相高效液体色谱分离

本文考察了七种黄酮化合物在Zorbax-ODS柱和Zorbax-CN柱上的反相高、效液体色谱行为,七种黄酮化合物分别在Zorbax—ODS柱上以甲醇-水-甲酸(75:25:0.1体积比)为流动相,在Zorbax-CN柱上以甲醇—水—甲酸(55:45:0.1体积比)为流动相得到较好的分离,考察了它们在Zorbax-ODS柱上的色谱保留行为与结构参数间的关系,结果表明有可能利用分子体积和基团亲水参数的大小预见黄酮化合物的色谱保留行为。     

杜仲黄酮的提取及抗氧化活性研究

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.     

Chronic quercetin exposure affects fatty acid catabolism in rat lung

Dietary quercetin intake is suggested to be health promoting, but this assumption is mainly based on mechanistic studies performed in vitro. Previously, we identified rat lung as a quercetin target tissue. To assess relevant in vivo health effects of quercetin, we analyzed mechanisms of effect in rat lungs of a chronic (41 weeks) 1% quercetin diet using whole genome microarrays. We show here that fatty acid catabolism pathways, like beta-oxidation and ketogenesis, are up-regulated by the long-term quercetin intervention. Up-regulation of genes (Hmgcs2, Ech1, Acox1, Pcca, Lpl and Acaa2) was verified and confirmed by quantitative real time PCR. In addition, free fatty acid levels were decreased in rats fed the quercetin diet, confirming that quercetin affects fatty acid catabolism. This in vivo study demonstrates for the first time that fatty acid catabolism is a relevant process that is affected in rats by chronic dietary quercetin. Received 6 July 2006; received after revision 29 August 2006; accepted 28 September 2006     

Modulation by polyamines of apoptotic pathways triggered by procyanidins in human metastatic SW620 cells

We showed previously that inhibition of polyamine catabolism with the polyamine oxidase inhibitor MDL 72527 (MDL) potentiates the apoptotic effects of apple procyanidins (Pcy) in SW620 cells. Here we report that Pcy caused an activation of the intrinsic apoptotic pathway through enhanced polyamine catabolism and mitochondrial membrane depolarization. MDL in the presence of Pcy caused a profound intracellular depletion of polyamines and exerted a protective effect on mitochondrial functions. MDL potentiation of Pcy-triggered apoptosis was reversed by addition of exogenous polyamines. In addition, MDL in combination with Pcy activated the extrinsic apoptotic pathway through enhanced TRAIL-death receptor (DR4/DR5) expression. Potentiation of Pcy-triggered apoptosis by MDL was inhibited when cells were exposed to specific inhibitors of DR4/DR5. These data indicate that the depletion of intracellular polyamines by MDL in the presence of Pcy caused a switch from intrinsic to extrinsic apoptotic pathways in human colon cancer-derived metastatic cells. Received 15 January 2008; received after revision 19 February 2008; accepted 7 March 2008     

桔皮类黄酮乙醇提取工艺研究

研究了桔皮类黄酮的乙醇提取工艺,以桔皮类黄酮质量分数为考察指标,通过单因素和正交试验,考察提取温度、乙醇质量浓度、固液比、提取时间对类黄酮质量分数的影响,结果确定最佳提取工艺条件为:提取温度70℃,固液比1∶25,乙醇质量分数70%,提取时间2 h.在最佳提取条件下,提取率可达22.03%.     

蒌蒿素原粉中总黄酮的提取及含量测定

以芦丁为对照品,通过正交实验,确定了以乙醇为溶剂的蒌蒿中总黄酮的最佳提取条件,在此条件下黄酮的得率为１．９４３％。     

树叶中具有生理活性的黄酮类化合物研究进展

综述了黄酮类化合物的提取与分离的方法,从定量分析和定性分析两方面介绍了黄酮类化合物的分析测定,列出了９种树叶的黄酮成分及其生理活性,阐明了黄酮类化合物的药效及其在抗氧化剂方面的应用前景。     

茵陈总黄酮的提取及初步纯化

研究了3种极性不同的大孔吸附树脂对茵陈黄酮的静态吸附行为,筛选出了较优的吸附分离树脂,并对洗脱剂进行了优化.络合显色法用于茵陈总黄酮含量的测定.结果表明：DM-301对茵陈黄酮吸附效果最好,70%的乙醇（体积比）作洗脱剂洗脱效果最好,解吸率最高.茵陈总黄酮的粗黄酮粉得率为17.8%,粗黄酮粉总黄酮含量为17.3%,茵陈总黄酮含量为干重的3.08%.     

山楂汁树脂降酸工艺的研究

研究离子交换树脂对山楂浸出汁降酸的效果及其影响因素.通过对比7种离子交换树脂对山楂浸出汁的静态吸附特性,测定山楂汁处理前后的总酸和黄酮含量的变化,筛选出适于山楂汁降酸的最佳离子交换树脂(D311).经实验分析,温度对树脂吸附能力影响不显著;D311树脂吸附优化条件为室温,100 mL/h流速处理;D311优化再生条件为在低流速下100 mL 1 mol/L NaOH洗脱处理.多次再生处理后,总酸吸附能力降低11.5%,黄酮吸附能力降低73.3%,黄酮的保存率可达88.8%.     

响铃草药材质量控制研究

目的:对响铃草药材质量进行控制.方法:以中国药典(2010年版)有关要求为依据,对响铃草药材的性状特征、显微鉴别、薄层色谱鉴别、总灰分、酸不溶灰分和醇浸出物进行分析,并用高效液相测定响铃草染料木素的含量.结果:详细描述了响铃草的性状和显微特征;薄层色谱中在与染料木素对照品相应位置上显相同颜色斑点;总灰分、酸不溶灰分和醇溶性浸出物的平均值分别为6.8%,1.7%和17.0%;在含量测定中染料木素在0.65～13.00μg/mL范围内线性关系良好(r=0.999 9),平均回收率为99.67%(n=6),RSD为0.86%.结论:本试验为响铃草药材的质量控制提供了可靠依据.