嗜热厌氧产乙醇杆菌乙醇代谢途径的初步研究

以乙醇产量和细胞密度的提高为目标,从碳源和氮源入手,对嗜热厌氧产乙醇杆菌THermoanaerobacter ethanolicus JW200的培养基作了初步优化以提高乙醇代谢途径中的关键酶的得率,便于提纯.葡萄糖浓度的提高对乙醇的产生有明显的诱导作用,但当葡萄糖浓度高于2%,乙醇产量反而下降.酵母粉对乙醇产量没有促进作用,单纯提高酵母粉浓度对细胞密度无显著影响,而同时提高葡萄糖和酵母粉浓度至2.0%,OD600最高可达2.0.2%葡萄糖,0.5%酵母粉对单位细胞乙醇产量的诱导效果最佳.T.ethanolicusJW200粗酶液中未检测到丙酮酸脱羧酶的活性,经亲和柱Cibacron Blue-3GA部分纯化,在NAD洗脱蛋白中检测到辅酶A依赖型乙醛脱氢酶的活性,表明辅酶A依赖型乙醛脱氢酶是该菌乙醇代谢途径中的关键酶,它和乙醇脱氢酶共同作用,将乙酰辅酶A转化成乙醇.     

Antiquitin, a relatively unexplored member in the superfamily of aldehyde dehydrogenases with diversified physiological functions

Antiquitin is a member of the aldehyde dehydrogenase superfamily. Sequence analyses indicate that the protein is highly conserved from plants to animals. The plant antiquitins are generally believed to play a role in osmoregulation and/or detoxification. The physiological functions of animal antiquitins remain largely elusive, their involvement in a number of human diseases has been implicated. Received 28 February 2006; received after revision 13 July 2006; accepted 31 August 2006     

RP-HPLC测定通脉粉针剂中丹参素及原儿茶醛的含量

利用反相高效液相层析法测定丹参素和原儿茶醛的含量以控制通脉粉针剂质量.结果表明,丹参素和原儿茶醛的平均回收率分别为98.01%、97.43%,变异系数为2.75%、2.83%.本法简便、准确,重现性良好,可用于含丹参复方中药制剂的质量控制。     

超声波和Zn/蒙脱石-ZnCl2使芳香醛片呐醇化

用超声波照射Ｚｎ/蒙脱石 ＺｎＣｌ_2和含50%(质量分数)ＴＨＦ的一些芳香醛水溶液2～3ｈ,芳香醛发生偶联反应,生成片呐醇,产率为23%～87%。2,4 二氯苯甲醛、β 苯基丙烯醛发生偶联反应时,片呐醇产率分别达到87.1%和74.8%;对甲基苯甲醛、糠醛发生偶联反应时,化学选择性较好;Ｚｎ/蒙脱石 ＺｎＣｌ_2重复使用3次,活性无显著降低。     

Isoquinolines,beta-carbolines and alcohol drinking: Involvement of opioid and dopaminergic mechanisms

Summary Two classes of amine-aldehyde adducts, the tetrahydroisoquinoline (TIQ) and beta-carboline (THBC) compounds, have been implicated in the mechanism in the brain underlying the addictive drinking of alcohol. One part of this review focuses on the large amount of evidence unequivocally demonstrating not only the corporeal synthesis of the TIQs and THBCs but their sequestration in brain tissue as well. Experimental studies published recently have revealed that exposure to alcohol enhances markedly the endogenous formation of condensation products. Apart from their multiple neuropharmacological actions, certain adducts when delivered directly into the brain of either the rat or monkey, to circumvent the brain's blood-barrier system, can evoke an intense and dose-dependent increase in the voluntary drinking of solutions of alcohol even in noxious concentrations. That the abnormal intake of alcohol is related functionally to opioid receptors in the brain is likely on the basis of several dinstinct lines of evidence which include: the attenuation of alcohol drinking by opioid receptor antagoists; binding of a TIQ to opiate receptors in the brain; and marked differences in enkephalin values in animals genetically predisposed to the ingestion of alcohol. Finally, it is proposed that the dopaminergic reward pathways which traverse the meso-limbic-forebrain systems of the brain more than likely constitute an integrative anatomical substrate for the adduct-opioid cascade of neuronal events which promote and sustain the aberrant drinking of alcohol.     

香草醛改性壳聚糖制备的研究

在水溶液中,壳聚糖与香草醛发生希夫碱反应,生成改性壳聚糖ＶＣＧ。ＶＣＧ的接枝率与反应时间、反应温度、接枝单体的加入量有关,最高可以达到５２％。反应的表观活化能为６．６４ ｋＪ／ｍｏｌ。通过红外光谱分析,可初步确定ＶＣＧ的分子结构。     

离子液体中 Sc（OTf）3催化下苯并［f ］喹啉-1，2-二羧酸酯的合成

在离子液体中，以芳醛、2-萘胺和丁炔二酸酯为原料，在 Sc（OTf）3催化下，通过 Povarov 反应，一步合成了3-芳基苯并[f]喹啉-1，2-二羧酸酯衍生物。产物结构均经红外、氢谱和高分辨质谱确定。与其它方法相比，该方法具有反应条件温和、产率较高和环境友好等优点。     

手性β-氨基醇催化的芳香醛对映选择性炔化反应

 手性β-氨基醇是不对称催化反应中应用最为广泛的手性配体之一.以L-苯丙氨酸为原料简捷合成的手性β-氨基醇L^*为手性配体,对不同取代芳香醛的对映选择性炔化反应进行了研究,结果表明其对该反应具有一定的不对称催化活性,光学收率(e.e值)最高达78.9%.     

Inhibition of aldose reductase by dihydroflavonols inEngelhardtia chrysolepis and effects on other enzymes

Astilbin and neoastilbin, dihydroflavonol rhamnosides fromEngelhardtia chrysolepis, showed potent inhibition of lens aldose reductase. Kinetic analysis showed astilbin exhibited uncompetitive inhibition against bothdl-glyceraldehyde and NADPH. These taxifolin glycosides were selective inhibitors of aldose reductase with no inhibition of NADH oxidase.     

由莰烯合成E型ω—甲基莰烯

本文用莰烯经Vilsmeier-Haack甲酰化反应制得的E型ω-甲酰基莰烯为原料,在草酸催化下使之与乙二硫醇缩醛化,再使所得的硫代缩醛在镍催化下发生氢解而合成了E型ω-甲基茨烯,提出了合成ω-甲基茨烯的一种新方法.所合成的硫代缩醛和ω-甲基莰烯均进行了纯化和质谱、红外和核磁共振等分析.