Comparative Analysis of Antioxidants in Hippophae rhamnoides L. Leaves by UPLC

[Objectives]The research aimed to compare antioxidation abilities of different extraction phases of Hippophae rhamnoides L. leaves extract and find its active marker. [Methods] H. rhamnoides L. leaves were extracted firstly by 75% of ethanol,and then were extracted by petroleum ether,chloroform,ethyl acetate and n-butanol in turn after decompression concentration. Via DPPH and ABTS^+ radical scavenging experiments and Fe^(3+) reduction experiment,antioxidation activity of each phase was evaluated. And chemical compositions related to its antioxidation activity were determined by using UPLC for qualitative identification. [Results] Antioxidation activity sequence of each phase was ethyl acetate phase≈n-butanol phase > alcohol extract of raw material > water phase > chloroform phase > petroleum ether phase. 33 kinds of chemical compositions were isolated from alcohol extract and extracts by using UPLC. [Conclusions] UPLC and antioxidation activity test were used simultaneously to analyze alcohol extract and extracts of H. rhamnoides L. leaves,which could fast and accurately determine extraction phase with the strongest antioxidation ability. The research is significant to study active ingredients and mechanism of antioxidation from H. rhamnoides L. leaves.

木槿叶的营养成分测定

以发掘新型蔬菜为目的,测定、分析了木槿叶中主要的营养成分与无机元素的含量.结果表明:(1)木槿叶中含有丰富的营养,其中蛋白质含量高达3.72%,脂肪含量达0.79%,粗纤维含量达9.83%,糖类含量达6.27%;(2)富含人体必需的微量元素,如钙、镁、铁、锌等.由此可见,木槿叶是一种很有开发前景的野生蔬菜.

荧光法猝灭测定木槿叶中混合氨基酸的总量

在乙酸-乙酸钠缓冲介质中,氨基酸能猝灭壳聚糖-茚三酮体系荧光,基于此,对木槿叶中混合氨基酸进行测定,并对该方法的测定条件进行了讨论.线性范围为0.5～3.0 mmol/L,检出限为0.1 mmol/L.木槿叶干粉中游离氨基酸的质量分数为10.18%,相对标准偏差为1.3%,回收率为102.5%～94.3%.

木槿叶的生药学研究

目的为木槿Hibiscus syriacus L.的质量评价标准提供科学资料。方法生药学鉴定法。结果描述木槿叶片和粉末的性状特征及显微特征。结论木槿叶的性状特征和显微特征可用于鉴别该生药。

水稻盐胁迫应答cDNA的克隆、表达和染色体定位(英文)

从150 mmol/L盐胁迫3 h和没有胁迫的耐盐水稻(Oryza sativa L.)品种特三矮2号叶片中提取mRNA,构建cDNA文库.通过示差筛选,得到3个盐胁迫应答cDNA克隆Ts1、Ts2和Ts3.Northerd分析表明,3 h的盐胁迫可使Ts1、Ts2和Ts3的转录水平明显上升;3～24 h期间,Ts1和Ts2的转录水平继续上升,而Ts3的转录水平则下降.序列分析表明,这3个cDNA克隆与已知功能的基因没有同源性.利用特三矮2号的耐盐亲本ZYQ8和粳稻JX1 7组合构建了DH群体和分子标记连锁图谱,将Ts1、Ts2和Ts3分别定位在第1、3和7染色体上.值得注意的是,Ts1、Ts2和Ts3与用同一群体定位的主效和微效耐盐QTL位于同一或相邻区域.

木槿叶中叶黄素的提取研究

叶黄素是天然胡萝卜素维生素A的衍生物,在预防老年性黄斑区病变,预防白内障,缓解视力疲劳方面有重要作用。以木槿叶为原料,通过单因素试验探讨烘干温度、烘干时间、萃取剂类型、浸提时间、浸提温度和料液比6个因素对木槿叶中叶黄素提取率的影响。通过正交试验L_9(3~4)对木槿叶中叶黄素的提取工艺进行优化。结果表明,木槿叶中叶黄素的提取的最佳工艺条件为:以无水乙醇为萃取剂,样品烘干时间3 h,萃取温度75℃,料液比1︰40 (g/mL)。在该工艺参数条件下木槿叶黄素提取率为0.043 8%。