银杏叶超氧化物歧化酶(SOD)活性研究

对超氧化物歧化酶邻苯三酚测活法的影响因素,如缓冲溶液组成和浓度、pH值、EDTA用量等因素进行了系统研究,通过比较邻苯三酚自氧化反应速率、线性回归方程的线性相关性和线性区间筛选出最佳条件,并根据优化的实验条件对银杏叶SOD提取液进行了活性研究.     

锰超氧化物歧化酶模型化合物的合成、表征及量化计算

以N,N,N',N'-四(2-苯并咪唑亚甲基)-1,2乙二胺(EDTB)为配体合成了Mn(EDTB)·(C6H5COO)·ClO4·3C2H6O·H2O的单核锰配合物.在乙醇溶液中得到其无色透明单晶,用X射线衍射方法对其晶体结构进行了测定.晶体学参数为:Mr=1011.41,三斜晶系,a=1.258(4)nm,b=1.314(4)nm,c=1.592(5)nm,α=105.33(5)o,β=99.75(5)o,γ=101.25(5)o,V=2.419(10)nm3,Dc=1.388Mg/cm3,Z=2,F(000)=1060,空间群为P1.对该化合物进行了紫外、红外表征及元素分析.利用G98量子化学程序包,在HF/Lan2DZ基组水平上对配合物进行了从头计算.采用经典的邻苯三酚自氧化法对配合物的生物活性进行了测定.     

Co-catalyzed autoxidation of alkene in the presence of silane. The effect of the structure of silanes on the efficiency of the reaction and on the product distribution

A systematic investigation of the structural effect of silanes on the Co-catalyzed reductive oxygenation of alkene in the presence of silane (Mukaiyama-Isayama reaction) showed that the efficiency of the reaction decreases with the increase of the steric bulk of the silanes. A similar trend was observed for the metal-exchange reaction between Co(III)-alkylperoxo complex and silane, too. The peroxidation of (S)-limonene, followed by deprotection of the derived silyl peroxides, provides a mixture of the corresponding monocyclic hydroperoxide 24 and the bicyclic one 25, the ratio being a marked function of the steric bulk of silanes.     

Microcalorimetric studies on the dismutation of superoxide anion catalyzed by superoxide dismutase

Ｓｕｐｅｒｏｘｉｄｅｄｉｓｍｕｔａｓｅ(ＳＯＤ,ＥＣ1.15.1.1),ｗｈｉｃｈｗａｓｆｏｕｎｄａｎｄｉｓｏｌａｔｅｄｆｒｏｍｂｏｖｉｎｅｅｒｙｔｈｒｏｃｙｔｅｓｂｙＭｃＣｏｒｄａｎｄＦｒｉｄｏｖｉｃｈｉｎ1969[1],ｉｓａｎｉｍｐｏｒｔａｎｔｍｅｍｂｅｒｏｆｔｈｅｆａｍｉｌｙｏｆｂｉｏｌｏｇｉｃａｌａｎｔｉｏｘｉｄａｎｔｓｔｒｅｓｓｅｎｚｙｍｅｓ.Ｔｈｉｓｅｎｚｙｍｅｈａｓｂｅｅｎｄｅｔｅｃｔｅｄｉｎａｗｉｄｅｒａｎｇｅｏｆｌｉｖｉｎｇｔｈｉｎｇｓａｎｄｈａｓｂｅｅｎｉｍｐｌｉｃａｔｅｄｉｎｔｈｅｉｎｔｅｒ…     

Autoxidation of 2-mercaptoethanol catalyzed by cobalt(II) phthalocyaninetetrasulfonate on colloidal particles

Cobalt(II) phthalocyaninetetrasulfonate (CoPcTS) is a highly active catalyst in aqueous media for the autoxidation of thiols to disulfides, and cationic polymers further enhance the activity. In this work we tested a variety of cationic polymer supports for the CoPcTS-catalyzed autoxidation of 2-mercaptoethanol in aqueous dispersions at 25°C. The order of activities is cationic polyelectrolytes > cationic polymer colloids > cationic colloidal silica > aqueous solution > ion exchange resins. Spectroscopic studies indicate that the high activity of the polyelectrolytes correlates with their ability to aggregate the CoPcTS. © 1992 John Wiley & Sons, Inc.     

应用极谱氧电极检测SOD活性研究

本文建立 SOD 活性测定的极谱氧电极法,同时比较了邻苯三酚和肾上腺素自氧化系统的工作条件和优缺点,结果提示,肾上腺素自氧化系统的最适条件为:30℃,0.1mol/LpH10.3碳酸缓冲液4.0ml,0.05mol/L 肾上腺素30μl,SOD 在0-0.8μg 间与产氧量成线性关系;邻苯三酚系统的工作条件与文献报道一致.实验发现肾上腺素系统灵敏度较高,但线性范围小,重复性与邻苯三酚系统一致.本文还应用极谱氧电极法筛选抗氧化天然活性物质,在若干动物、植物及酵母中进行了SOD 活性测定,证明该法简便、快速、灵敏。     

中华猕猴桃营养生物学效应研究——Ⅲ.浓缩果汁对家兔血液红细胞的邻苯三酚自氧化抑制效应

采用邻苯三酚自氧化抑制法,对口服中华猕猴桃浓缩果汁家兔血液红细胞的邻苯三酚自氧化抑制效应的试验表明,按50kg体重人体,每日食用0.5kg果汁剂量,持续5周服用中华猕猴桃浓缩果汁的家免,其血液红细胞邻苯三酚自氧化反应抑制率明显升高。与服用前正常值73.7％对比,1—5周依次为129.1％,153.1％,133.4％,154.9％和150.8％。停服果汁2周和4周的测定值为111.8％和114.8％。结果提示,口服中华猕猴桃浓缩果汁有明显增强家兔血液红细胞的邻苯三酚自氧化抑制效应,抑制率比正常值提高1倍。猕猴桃果汁与同等剂量试剂抗坏血酸平行抑制试验结果,猕猴桃果汁的自氧化抑制率较试剂抗坏血酸高2个剂量级。     

碱性条件下氧气液相氧化邻硝基甲苯的机理分析

讨论了碱性条件下常压氧气液相氧化邻硝基甲苯的反应机理。结合强碱对反应的影响及邻硝基甲苯自身的结构特征,提出反应中邻硝基甲苯首先脱氢生成苄阴离子,而后直接与氧作用生成苄自由基,从而引发反应的历程。详细解析了反应在2-甲氧基乙胺中所得的EPR谱图,证明了反应中确有自由基的存在,并发现反应还受到溶剂的影响,存带有醚键的有机胺溶剂中,反应更容易进行。     

Active Oxygen Radical Scavenging Ability of Water-Soluble β-Alanine C_(60) Adducts

The bioactivity study of C60 and its relative derivatives is of considerable importance. Functional fullerenes have peculiar biological activities, such as enzymatic inhibition, anti-HIV activity, neuroprotection, antibacterial activity, DNA cleavage, and photodynamic therapy et al.1. Neuroprotective properties are based on the facts that functional fullerenes have antioxidant properties and high reactivity toward free radical2. Active oxygen radical in biological system mainly include…