Increment of antioxidase activity of transgenic tobacco with betaine aldehyde dehydrogenase

Superoxide dismutase (SOD) activity in the leaves of transgenic tobacco plants with betaine aldehyde dehydrogenase (BADH) gene was about 36% higher than that in the control plants (parent plants), activities of peroxidase (POD) and catalase (Cat) increased by about 62% and 88% respectively. Activities of ascorbate peroxidase (AsSPOD), dehydroascorbate redutase (DAsAR) and glutathione reductase (GR) in ascorbate-glutothion pathway located at chloroplasts increased by 67.7%, 47.9% and 38.8% respectively. These results indicated that the H₂O₂ produced by SOD catalyzing superoxide anion radicals (O^-₂) could be fully decomposed, and could not derive to form the strongest toxicant radicals ·OH. This is the first report to elucidate quantitatively that the activities of two kinds of antioxidative enzymes decomposed radicals and active oxygen were matched. Photoinhibition tolerant capacity of the transgenic tobacco plants was 35% higher than that in the parent plants. Increment of photoinhibition tolerant capacity in the transgenic tobacco plants might be due to increment of antioxidative enzymes activities, in turn being able to more effectively scavenge active oxygen and radicals, protect organization and function of chloroplasts. These results showed that the increment of antioxidative enzymes activities in the transgenic tobacco might be one of the reasons for the increment of resistance in the transgenic tobacco.     

肉桂醛邻氨基苯甲酸席夫碱锌配合物的合成及抗菌活性试验

用天然醛类——肉桂醛与邻氨基苯甲酸合成席夫碱及其锌配合物,并用红外、元素分析、测定结晶水等方法进行化合物表征．将席夫碱锌配合物用4种细胞菌株：金黄色葡萄球菌、大肠埃希氏、伤寒沙门氏、铜绿假单胞进行抗菌活性试验,得到较满意的结果．     

Electrochemical-voltammetry behavior of several aromatic aldehydes in acid solution

The electrochemical-voltammetry behavior of vanillin, heliotropin, anisaldehyde on the surface of Pt, Au electrodes in acid solution has been studied by means of the electrochemical cyclic voltammetry method. It was found that the electrochemical processes of them are irreversible on both Pt and Au electrodes. The electrochemical activity of vanillin is stronger than heliotropin's and heliotropin's is stronger than anisaldehyde's on Pt electrode. While the electrochemical activity of anisaldehyde is stronger than heliotropin's and vanillin's is the weakest on Au. The results indicate that when they are used as additives for electroplating, they must be consumptive, and it will improve the leveling ability of plating solution and brightness of the deposition layer. Biography: Zhou Xiao-rong (1977-), female, Ph.D candidate, research direction: electrochemistry.     

Selectivity determinants of the aldose and aldehyde reductase inhibitor-binding sites

Aldose reductase and aldehyde reductase belong to the aldo-keto reductase superfamily of enzymes whose members are responsible for a wide variety of biological functions. Aldose reductase has been identified as the first enzyme involved in the polyol pathway of glucose metabolism which converts glucose into sorbitol. Glucose over-utilization through the polyol pathway has been linked to tissue-based pathologies associated with diabetes complications, which make the development of a potent aldose reductase inhibitor an obvious and attractive strategy to prevent or delay the onset and progression of the complications. Structural studies of aldose reductase and the homologous aldehyde reductase in complex with inhibitor were carried out to explain the difference in the potency of enzyme inhibition. The aim of this review is to provide a comprehensive summary of previous studies to aid the development of aldose reductase inhibitors that may have less toxicity problems than the currently available ones. Received 4 December 2006; received after revision 12 February 2007; accepted 20 April 2007     

用空气作绿色氧化剂合成苯并咪唑的新方法

报道了一种利用空气作为氧化剂由邻苯二胺和醛为原料合成苯并咪唑的新方法.该方法以DMF为溶剂,等物质的量的邻苯二胺和醛反应一锅合成目标产物,产率较好(64%~90%),且具有操作简单、条件温和、环境友好等优点.     

CeO2／O3催化氧化对滤后水中小分子副产物生成的影响

考察了连续流体系中,滤后水经氧化铈催化臭氧氧化（CeO2／O3）后小分子醛、酮、羧酸及酮酸副产物的生成情况．发现CeO2／O3明显提高了DOC和SUVA的去除率,醛、酮副产物的产量比单独O3氧化后的增加了8％,而羧酸和酮酸的产量却比单独O3氧化后的分别降低了28％和54％．羧基类副产物大幅降低的原因主要与CeO2表面Ce（Ⅳ）对羧基官能团较强的络合亲合力有关．CeO2／O3氧化后小分子副产物总量比单独O3氧化后的降低了23％,但用小分子副产物总量折算有机碳占DOC的比例来间接显示氧化后剩余DOC的可生物降解性,结果表明,CeO2／O3进一步提高了滤后水剩余DOc的可生化性．     

α,β-不饱和糖烯醛的合成

为探讨α,β-不饱和糖烯醛的最佳合成条件,以五、六元糖醛为起始原料,在不同温度下合成了该类化合物.结果表明,高温有助于消除反应的进行.进一步探讨了糖氧化合成不饱和糖烯醛的反应,并首次实现了由苄基保护的糖向不饱和糖烯醛的一步合成.     

毛细管电泳-柱端安培检测装置的研制

设计了一种喷壁式毛细管电泳安培检测装置 .用原儿茶醛和原儿茶酚作为模型化合物考察了分离电压、电极与毛细管出口之间的距离对噪音和电极响应的影响 ,研究了清洗步骤对测定结果重视性的影响 .对该检测器的性能进行了测试 ,其分离效率可达 1.2× 10 5(原儿茶醛 )和1.1× 10 5(原儿茶酚 ) ,原儿茶醛和原儿茶酚检测限分别为 0 .2 5和 0 .50 μg/mL .     

乙酸乙酯生产工艺现状及发展趋势

介绍了国内外乙酸乙酯的生产工艺现状和发展趋势，并对酯化法和乙醛缩合法的工艺条件，技术经济情况进行了对比。