Kinetic parameters of oscillating reaction of amino acid- BrO3^——Mn^2＋-H2SO4-acetone system

In the previous papers[1—3], the oscillating reactionusing amino acids as organic substrates was studied. Inorder to obtain information about the kinetic parameters ofoscillating reaction of amino acids in amino acid- BrO3 - ?Mn2 -H2SO4-acetone sy…     

川明参与北沙参中氨基酸的测定

测定了中药川明参和北沙参中氨基酸的含量和组成。结果表明：川明参和北沙参至少含１３种氨基酸，其中含丰富的天冬氨酸和谷氨酸，还含有人体必需的七种氨基酸，为全面深入地研究和开发这两种药物提供了参考依据     

复合氨基酸螯合铜的制备工艺研究

以动物蛋白粉为复合氨基酸来源，对复合氨基酸螯合铜的合成工艺条件地初步的探讨，研究了反应液pH值、反应温度、反应时间对螯合反应的影响。确定了合适的反应条件为：反应液pH＝11.0，反应温度为常温，反应时间为30min，并用红外光谱法鉴定了产品。     

生态环境对益智化学组成,含量的影响

本研究测定结果表明,益智朔果百粒重和所含的营养成分与产地所处的纬度、海拔高度、环境条件相关密切。益智所含的总糖、粗脂肪、蛋白质、总氨基酸量等营养物质和10余种矿质元素,可随着种类、产地的生态效应不同而异。差异程度总的趋向是海南东南沿海地区>中部低山>北部台地。野生种果质优于栽培种。益智果是食、药兼用珍品,值得扩种、综合利用。     

Ammonia and amino acid transport across symbiotic membranes in nitrogen-fixing legume nodules

Biological nitrogen fixation involves the reduction of atmospheric N₂ to ammonia by the bacterial enzyme nitrogenase. In legume-rhizobium symbioses, the nitrogenase-producing bacteria (bacteroids) are contained in the infected cells of root nodules within which they are enclosed by a plant membrane to form a structure known as the symbiosome. The plant provides reduced carbon to the bacteroids in exchange for fixed nitrogen, which is exported to the rest of the plant. This exchange is controlled by plant-synthesised transport proteins on the symbiosome membranes. This review summarises our current understanding of these transport processes, focusing on ammonia and amino acid transport. Received 5 June 2000; revised 13 July 2000; accepted 14 July 2000     

Regulation of carbohydrate metabolism by the optic tentacles of the garden snailCryptozona ligulata (Gastropoda-Stylommatophora)

Summary The presence of a hyperglycemic factor in the optic tentacles of the snailC. ligulata is reported here. A preliminary characterization based on crude extracts indicates the factor to be water-soluble, heat labile and to be an albumin. The ablation of optic tentacles and injection of optic tentacle extract into operated and normal snails caused a rise in blood sugar, total carbohydrate and glycogen in the foot muscle and mantle and a decrease in hepatopancreatic glycogen. The ablation also caused a fall in blood free amino acids and a rise in the tissues, which was reversed in the blood and foot muscle by injection of the extract. Possible conversion of amino acids to total carbohydrates and glycogen by gluconeogenesis is suggested.     

Characterization of victorin C,the major host-selective toxin fromCochliobolus victoriae: Structure of degradation products

Summary Several host-selective toxins have been isolated in pure form culture filtrates ofCochliobolus victoriae. Acid hydrolysis of the major toxin, victorin C (apparent mol.wt 796), produced five fragments to which structures1–5 have been assigned. Spectroscopic techniques revealed that the toxin contains an additional subunit corresponding to6; thus all the components of victroin C are accounted for.     

反相高效液相色谱法测定土豆中的果酸

本文阐述用反相高效液相色谱及紫外可见检测器，流动相为０．０１Ｍ（ＮＨ４）２ＨＰＯ４，用Ｈ３ＰＯ４调节ＰＨ值为２．５，使果酸得到分离。用标准酸样的直线方程进行定量。并对土豆中的五种果酸作了定量分析。回收率达９２％以上