生物柴油脂肪酶产生菌的筛选及培养条件研究

从长期被脂肪油脂污染的土壤中分离得到能够以橄榄油为唯一碳源和能源的脂肪酶产生菌,通过在含有演．甲酚紫的培养基培养筛选一株脂肪酶活力最强的菌株,经显微镜观察和生理生化实验,初步鉴定为巨大芽孢杆菌（Baeillac megaterium）。在pH7．0,橄榄油浓度在812mg／L和以1．5％蛋白胨为氮源的培养条件下三天,脂肪酶的活力最大,达到19．3U／mL。     

Response to temperature stress of reactive oxygen species scavenging enzymes in the cross-tolerance of barley seed germination

A number of studies have shown the existence of cross-tolerance in plants, but the physiological mechanism is poorly understood. In this study, we used the germination of barley seeds as a system to investigate the cross-tolerance of low-temperature pretreatment to high-temperature stress and the possible involvement of reactive oxygen species (ROS) scavenging enzymes in the cross-tolerance. After pretreatment at 0 °C for different periods of time, barley seeds were germinated at 35 °C, and the content of malondialdehyde (MDA) and the activities of ROS scavenging enzymes were measured by a spectrophotometer analysis. The results showed that barley seed germinated very poorly at 35 °C, and this inhibitive effect could be overcome by pretreatment at 0 °C. The MDA content varied, depending on the temperature at which seeds germinated, while barley seeds pretreated at 0 °C did not change the MDA content. Compared with seeds germinated directly at 35 °C, the seeds pretreated first at 0 °C and then germinated at 35 °C had markedly increased activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and glutathione reductase (GR). The SOD and APX activities of seeds germinated at 35 °C after 0 °C-pretreatment were even substantially higher than those at 25 °C, and GR activity was similar to that at 25 °C, at which the highest germination performance of barley seeds was achieved. These results indicate that low-temperature pretreatment can markedly increase the tolerance of barley seed to high temperature during germination, this being related to the increase in ROS scavenging enzyme activity. This may provide a new method for increasing seed germination under stress environments, and may be an excellent model system for the study of cross-tolerance.     

乙醇对离体蟾蜍心脏活动及心肌酶的影响

目的观察不同浓度乙醇按不同灌流顺序对离体蟾蜍心脏活动的影响,探讨其作用机制。方法蟾蜍24只,雌雄不限,随机分为正常对照组、乙醇浓度递增灌流组、乙醇浓度递减灌流组,每组8只。结果与正常对照组相比：两种灌流顺序的乙醇组都显示心率减慢（P〈0.01或P〈0．05）,心肌收缩幅度减小（P〈0．01）,心肌ATP酶和超氧化物歧化酶（SOD）含量减少（P〈0．01）,丙二醛（MDA）含量增多（p〈0．01）;递增组与递减组相比,无显著差异。结论急性乙醇中毒可导致离体蟾蜍心肌酶发生改变,对心率和心肌收缩幅度有抑制作用,且抑制作用呈浓度依赖性.     

重金属离子对猪血SOD的活力与构象影响

以猪血为材料,以超氧化歧化酶（简称SOD,EC1．15．1．1）为研究对象,经有机溶剂沉淀法得SOD酶液,测定SOD酶中铜锌含量比例．研究Hg^2＋、Pb^2＋、Cd^2＋等不同重金属离子对SOD活力与构象影响,结果表明：猪血SOD酶中含有等量的铜与锌．Hg^2＋、Cd^2＋对酶活力均表现为低浓度激活高浓度抑制作用．而Pb^2＋在考察的浓度范围内表现激活作用,荧光光谱显示三种重金属离子的存在均引起酶构象的改变．     

Colilert(科立得)固定底物技术酶底物法的快速检测方法分析

文章验证与分析了固定底物酶底物法检测水中的粪大肠菌群,与多管发酵法相比,该技术具有结果准确、测试简单、方便等优点。     

Optimization of angiotensin I-converting enzyme （ACE） inhibition by rice dregs hydrolysates using response surface methodology

INTRODUCTION Angiotensin I-converting enzyme (ACE) canconvert angiotensin I to angiotensin II which isknown to be a strong vasopressor, besides inactivat-ing bradykinin conducive to lowering blood pressure(Ondetti et al., 1977). This enzyme also playsphysiological roles in the regulation of local levels ofother endogenous peptides, such as enkephalins andsubstace P. Therefore, inhibition of ACE can reducethe activity of angiotensin II, but increase bradykininand enkephalins levels, …     

春季珊瑚树芽抗寒物质及抗氧化酶系的变化

珊瑚树芽内可溶性蛋白含量、酚类物质、POD等含量在2-4月份间呈逐渐下降的趋势，而超氧阴离子(O2^-)、SOD、MDA、脂质过氧化产物等则相反，在2—4月份间呈逐渐升高趋势。这说明：珊瑚树生长芽在开春期间可能因体内的可溶性蛋白、POD、酚类物质含量的下降而致使植物的抗寒性减弱。芽生长期间超氧阴离子产生增加，其歧化酶SOD也呈上升趋势，生长时芽内MDA以及脂质过氧化产物含量较高，表明此时生长芽的抗逆性很弱。     

渗透胁迫对芦苇愈伤组织保护酶活性及同工酶的影响

在PEG - 6 0 0 0的渗透胁迫下 ,沙生芦苇胚性愈伤组织 (SREC)和水生芦苇胚性愈伤组织 (WREC)的过氧化氢酶 (CAT)、过氧化物酶 (POD)的活性升高明显 ,超氧化物歧化酶 (SOD)活性呈小幅度升高 ,SREC的 3种酶的活性升幅大于WREC ;SREC的POD和CAT同工酶谱带数多于WREC ,二者的SOD同工酶谱带数在胁迫前后无变化 .胁迫的同时施加ABA对WREC的影响较大     

复合酶制剂对断乳肉兔生长性能的影响

选择 35日龄新西兰白兔 2 5只 ,随机分成A、B、C、D、E五组 ,A、B、C、D组为试验组 ,E组为对照组。试验组分别添加 0 .1 % ,0 .3%和 0 .5 %、0 .7%资源复合酶 ,研究不同水平的复合酶对断乳肉兔的生长性能的影响。结果表明 ,在饲料中添加复合酶制剂 ,试验组与对照组相比 ,试验组日增重分别提高 1 8.61 %、2 0 .73%、2 0 .95 %、2 0 .80 % ,经生物统计方差分析和SSR法多重比较 ,差异极显著 ,而组间差异不显著 ;料重比分别下降 2 6.2 7% (P <0 .0 1 )、 2 8.0 4 %(P <0 .0 1 )、2 9.1 7% (P <0 .0 1 )和 2 8.0 8% (P <0 .0 1 ) ,但组间差异不显著。试验组经济效益明显。     

体育高考前的准备工作初探

从考前的休息与训练、考前的饮食、考前准备活动、考前心理准备等四个方面探讨了考生在体育高考前的准备工作,并提出一些建议.