野山参叶,园参叶和西洋参叶与氨基酸含量

报道了野山参叶中氨基酸的含量并与园参叶,国产西洋参中氨基酸含量进行了对比分析。     

不同年龄的野山参和园参中氨基酸含量的对比研究

<正> 人参(Panax ginseng C.A.Meyer)系五加科植物的干燥根,是驰名中外的一味珍奇草药。由于野生的人参(野山参)资源越来越少,价格十分昂贵,因此长期以来人们大量地进行人工栽培。人工栽培的人参称园参。关于园参国内外大量的研究确认人参皂甙是其主要的有效成分。除此还含有氨基酸、肽类、多糖、脂肪酸等化合物。然而园参和野山参化学成份有何差异至今国外尚无报道。我们受吉林卫生厅的委托,对长白山野山参中人参皂甙、氨基     

吉林野山参与世界各地人参根中氨基酸含量的特征性研究

<正> 人参(Panax ginseng C.A.Meyer)系五加科(Ariliaceac)植物的干燥根,是驰名中外的珍贵药材,其中包括园参、野山参、移山参、朝鲜人参(高丽参)、日本人参(东洋参)。除此以外,同属于五加科人参属植物的还有产于美国、加拿大的西洋参(Panax quinquefolium L)。野山参由于突出的药理作用,加之样品奇缺,价格最为昂贵。目前世界各国有关野     

野生植物灰叶堇菜、白术中氨基酸含量分析

本文利用PICO-TOG高效氨基酸分析仪对野生植物灰叶堇菜、白术中的氨基酸成分进行了分析,结果表明：灰叶堇菜、白术中都至少含有17种氨基酸,具有良好的开发利用价值。     

野生植物灰叶堇菜、白术中氨基酸含量分析

本文利用PICO-TOG高效氨基酸分析仪对野生植物灰叶堇菜、白术中的氨基酸成分进行了分析,结果表明:灰叶堇菜、白术中都至少含有17种氨基酸,具有良好的开发利用价值。     

三七叶、人参叶和西洋参叶皂苷类成分的研究(英文)

三七叶、人参叶和西洋参叶其皂苷类成分相近,但专属性成分各异,皂苷类成分的分布比例也各不相同。本文建立了HPLC-UV法测定上述皂苷成分的方法,经过方法学考察,各种皂苷成分精密度好、加样回收率高,方法可靠。11种皂苷成分总含量顺序为:西洋参叶>人参叶>三七叶;二醇组皂苷成分含量:西洋参叶>三七叶>人参叶;三醇组皂苷成分含量:人参叶>西洋参叶>三七叶。西洋参叶中二醇组皂苷和人参叶中三醇组皂苷含量明显高于其他。西洋参叶中人参皂苷Rb3和Rd的含量之和占11种皂苷成分的60%以上。鉴于其中人参皂苷的高含量,三七叶、人参叶和西洋参叶应该作为皂苷来源得到充分利用;不同的皂苷成分有不同的药理活性,应基于它们的皂苷组成和比例选择性进行研究和开发。     

银杏叶中氨基酸的含量测定

本文测定了不同时期采集的银杏树叶中１７种氨基酸的含量。结果表明,银杏叶中水解氨基酸的总含量分别为１５．０９％,１１．８７％,９．９７％,和７．１４％;游离氨基酸的总含量分别为０．７６％,０．２８％。     

荞麦中氨基酸含量的分析

采用日立８３５—５０型氨基酸分析仪,测定了九个品种荞麦的氨基酸含量,结果表明：①谷氨酸的含量在荞麦中的比例最高。②荞麦中赖氨酸的含量高于一般谷实类赖氨酸的含量。③苦荞与甜荞之间在氨基酸总量上无显著性差异。     

基于氨基酸分类的基本氨基酸秩序的研究

在分析了基本氛基酸分类的基础上,提出基本氛基酸存在着一种参考排列秩序,以此固定的氛基酸排列秩序为参考标准,分析蛋白质一级结构相对此参考秩序的变化规律,能够找到构成蛋白质的二级结构的某些信息．     

几种海产品中氨基酸及牛磺酸含量的比较

通过对几种海产品进行氨基酸分析,确证海产品中除了含有常见的１８种氨基酸外,还有含量较高的牛磺酸,对其进行了研究探讨。     

云南省常见野生食用菌的氨基酸含量

采用国家标准方法对云南41种常见野生食用菌鲜菌中17种氨基酸进行了定量,结果表明这些食用菌中氨基酸种类齐全、含量丰富,其中玉蕈离褶伞、灰褐牛肝菌、球形鸡枞菌和条纹鸡枞菌等总氨基酸含量较高。     

Evolutionarily Conserved Optimization of Amino Acid Biosynthesis

The “cognate bias hypothesis” states that early in evolutionary history the biosynthetic enzymes for amino acid x gradually lost residues of x, thereby reducing the threshold for deleterious effects of x scarcity. The resulting reduction in cognate amino acid composition of the enzymes comprising a particular amino acid biosynthetic pathway is predicted to confer a selective growth advantage on cells. Bioinformatic evidence from protein-sequence data of two bacterial species previously demonstrated reduced cognate bias in amino acid biosynthetic pathways. Here we show that cognate bias in amino acid biosynthesis is present in the other domains of life—Archaebacteria and Eukaryota. We also observe evolutionarily conserved underrepresentations (e.g., glycine in methionine biosynthesis) and overrepresentations (e.g., tryptophan in asparagine biosynthesis) of amino acids in noncognate biosynthetic pathways, which can be explained by secondary amino acid metabolism. Additionally, we experimentally validate the cognate bias hypothesis using the yeast Saccharomyces cerevisiae. Specifically, we show that the degree to which growth declines following amino acid deprivation is negatively correlated with the degree to which an amino acid is underrepresented in the enzymes that comprise its cognate biosynthetic pathway. Moreover, we demonstrate that cognate fold representation is more predictive of growth advantage than a host of other potential growth-limiting factors, including an amino acid’s metabolic cost or its intracellular concentration and compartmental distribution. Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. Reviewing Editor: Dr. Niles Lehman Ethan O. Perlstein and Benjamin L. de Bivort contributed equally to this work.     

离子膜法技术在氨基酸制备中的探讨

介绍了离子交换膜分离技术原理及其在氨基酸制备中的应用工艺,设计提出了新型反馈离子交换膜分离工艺,取代传统的老工艺,实现了工业化大生产。     

离子膜法技术在氨基酸制备中的应用探讨

介绍了离子交换膜分离技术原理及其在氨基酸制备中的应用工艺 ,设计提出了新型反馈离子交换膜分离工艺 ,取代传统的老工艺 ,实现了工业化大生产。     

Amino Acid Neurotransmitters in the CNS: Properties of Diaminobutyric Acid Transport

Uptake of L-2,4-diaminobutyric acid (DABA), a positively charged analogue of gamma-aminobutyric acid (GABA), by a synaptosomal fraction isolated from rat brain occurred with a Km of 54 +/- 12 microM and a Vmax of 1.3 +/- 0.2 nmol/min/mg protein. The transport of DABA was inhibited competitively by GABA whereas that of GABA was affected in the same manner by addition of DABA. The maximal accumulation of DABA ([DABA]i/[DABA]c) was observed to increase as the second power of the transmembrane electrical potential ([K+]i/[K+]e) and the first power of the sodium ion concentration gradient. These findings indicate that DABA is transported on the GABA carrier with a net charge of +2, where one charge is provided by the cotransported Na+ and the second is contributed by the amino acid itself. Since uptake of GABA, an electroneutral molecule, is accompanied by transfer of two sodium ions, the results obtained with DABA suggest that one of the sodium binding sites on the GABA transporter is in proximity to the amino acid binding site.     

外源一氧化氮、水杨酸和过氧化氢对烟草叶片游离氨基酸和可溶性蛋白含量的影响

测定了NO、SA和H2O2三种信号分子对烟草氮代谢产物游离氨基酸、脯氨酸和可溶性蛋白质含量的影响。结果表明：NO、SA和H2O2能调节烟草脯氨酸、游离氨基酸和可溶性蛋白质含量。低浓度的NO和H2O2处理后12h能提高脯氨酸含量,而较高浓度的NO、SA和H2O2处理降低烟草脯氨酸和游离氨基酸含量;三者对脯氨酸、游离氨基酸和可溶性蛋白质含量的影响具有相似性。     

人参皂苷降脂作用的研究

为了测定西洋参总皂苷及单体皂苷是否有降脂活性,通过体外实验分别测定脂肪分解活性、小肠刷状缘膜小囊吸收脂肪酸、三油酸甘油酯油酸的释放率。结果表明,西洋参茎叶总皂苷在0．5g／L浓度时,对胰脂肪酶活性的抑制率为90％;人参皂苷Rc,Rb1,Rb2对胰脂肪酶活性均显示很强的抑制作用,在0．5g／L浓度时抑制率分别为100％,96％,97％。西洋参总皂苷和人参皂苷Rc,Rh,Rb2可以通过抑制胰脂肪酶活性起到降脂作用。