Modulation of ethion-induced hepatotoxicity and oxidative stress by vitamin E supplementation in male Wistar rats

Organophosphorus insecticides (OPIs) may induce oxidative stress leading to generation of free radicals and alteration in antioxidant system of animals. Many studies reported that enzymatic and non-enzymatic antioxidant may play protective role against OPIs induced toxicity in human and rats. The aim of present study was to investigate the possible protective role of vitamin E on ethion-induced hepatotoxicity in rats using qualitative, quantitative and biochemical approaches. Adult male albino rats of Wistar strain were randomly divided into four groups; each group consists of six animals. Animals were treated for a period of 28 days. Group I (control group received corn oil); Group II [ethion treated (2.7 mg/kg bw/day)]; Group III (vitamin E treated (50 mg/kg of bw/day)]; Group IV (ethion + vitamin E treated). Animals were sacrificed after 7, 14, 21 and 28 days by decapitation and liver tissue was used for the measurement of proteins, lipid peroxidation (LPO), reduced glutathione (GSH) content and activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) glutathione reductase (GR) and glutathione-S-transferase (GST). Erythrocytes were analyzed for acetyl cholinesterase activity. The result of this study shows that in vivo administration of ethion caused a significant induction of oxidative damage in liver tissue as evidenced by increased level of LPO and decreased GSH content. Ethion toxicity also led to a significant increase in the activities of SOD, CAT, GPx and GST in liver tissue. In addition, decrease in GR activity was observed in ethion administered rats compared to control. Histopathological findings revealed that exposure to ethion caused damage in liver tissue. However, simultaneous supplementation with vitamin E restored these parameters partially. In conclusion, the results of the current study revealed that ethion-induced toxicity caused lipid peroxidation, alterations in the antioxidant enzymes and histopathological changes in liver. Supplementation of vitamin E exhibited protective effect by inhibiting ethion-induced toxicity in liver and erythrocytes.     

朱砂叶螨对阿维菌素及高温的交互耐性

以朱砂叶螨敏感种群(SS)、抗阿维菌素种群(RA)和耐高温种群(RH)为材料,应用生物测定方法以及荧光实时定量PCR技术,研究朱砂叶螨抗药性和耐高温间存在的交互耐性及机制.结果显示:46℃高温下RH和RA种群的半致死时间(LT50)显著长于SS种群,其顺序依次是:RHRASS,阿维菌素对朱砂叶螨的半致死浓度(LC50)各种群间的顺序依次是:RARHSS,其中,RH和RA种群显著高于SS种群.这表明长期的高温胁迫能诱导其对阿维菌素药剂的抗性,同样对阿维菌素的抗药性也能诱导其对高温的耐性.SS、RA和RH经阿维菌素处理后体内O2?(超氧自由基)含量分别是对照的2.08、1.85和2.00倍,SOD(超氧化物歧化酶)活性分别是对照的3.81、4.84和4.26倍,CAT(过氧化氢酶)和POD(过氧化物酶)活性也都高于对照;经高温(40℃)和低温(4℃)处理后,O2?及SOD、CAT和POD活性也表现出相同的趋势.说明朱砂叶螨虫体内的O2?、SOD、CAT和POD与阿维菌素药物和热(冷)刺激有关,RA和RH在长期阿维菌素或高温胁迫作用下对保护酶活性的诱导能力加强.朱砂叶螨Tc HSP90 mRNA在正常情况下的表达是RA和RH高于SS,分别是SS的1.64倍和1.29倍,经阿维菌素、高温(40℃)和低温(4℃)处理后,RA和RH的表达量显著高于SS,表明朱砂叶螨HSP90在抗药性和耐热性方面发挥了作用.     

复合酶法提取南瓜多糖及其抗氧化性的研究

[目的]优化复合酶法提取南瓜多糖的工艺条件,研究南瓜多糖的抗氧化性.[方法]采用单因素试验设计研究了不同提取时间、温度、料液比、pH对南瓜多糖提取率的影响,并通过正交试验确定了提取南瓜多糖的最佳的复合酶配比和最佳提取条件.采用水杨酸法检测南瓜多糖对羟基自由基(·OH)和改进的邻苯酚自氧化法检测其对超氧阴离子自由基(O2)的清除效果.[结果]当纤维素酶的浓度为1.0%、果胶酶为1.5%、木瓜蛋白酶为1.O%时,以及温度为40℃、pH=4.6、料液比为1∶30、提取时间为30 min的条件下南瓜多糖的提取率最高;南瓜多糖对·OH具有较好的清除效果,对O2有部分清除作用.[结论]该研究为南瓜多糖的研究及应用提供了基础资料. Abstract： [Objective] This paper aims to study a new method of extracting pumpkin polysaccharide from pumpkin.Single factor experiments were conducted to examine the effects of extracting time,temperature,the solid-liquid ratio and pH value on the extraction yield of polysaccharide from pumpkin.[Method]The best enzyme ratio and extraction conditions for complex enzymes extraction were determined through orthogoo-pheno methods respectively.[Results]The results showed that the biggest extraction yield of polysaccharide from pumpkin can be got when adding 1% cellulose enzyme,1.5% pectinase,1.0% papain and Na2 HPO4-citric acid buffer solution (pH was 4.6),and oscillating for 30 min weak activity to scavenge O2-. [Conclusion] This study provided basic data for research and application of Pumpkin polysaccharide.     

改进点样器对血清蛋白膜电泳分离效果的影响

在醋酸纤维薄膜电泳分离人血清蛋白质实验中,为了使实验取得了廉价、简捷、分离效果更好的效果,改用毛细管以及自制点样器点样,经过多次试验,不仅同时结合GIS-2009(Tianneng)图谱分析仪成像和蛋白质指纹图谱分析,结果显示:改制订书针效果优于毛细管和载玻片,而且点样量在3μL时效果优于2μL和1μL。确定最佳点样为:自制的订书针,点样量3μL。     

Pb 胁迫对圆叶无心菜(Arenaria rotumdifolia Bieberstein)生长和生理特征的影响

通过室内水培圆叶无心菜幼苗,研究不同浓度Pb对圆叶无心菜生长、叶绿素含量、丙二醛含量和细胞膜透性的影响。结果表明,随着Pb处理浓度的增加,植物生长受到抑制,叶绿素含量呈现先上升后下降的变化趋势,丙二醛含量和细胞膜透性均呈上升的变化趋势。铅浓度为50 mg.L-1时,圆叶无心菜株高、根长以及生物量和叶绿素含量均比对照含量有所增加;铅浓度大于100 mg.L-1时,植株株高和根长的生长受到抑制,地上部鲜重和地下部鲜重均减少,叶绿素含量降低,丙二醛含量和细胞膜透性都显著增加。     

半透膜微萃取方法的建立及其在测定土壤间隙水中憎水性有机污染物的应用

提出了一种新型的基于半透膜被动采样技术的微萃取方法(semi-permeable membrane based micro-extraction,SPM-ME),并以菲为模型污染物,测试了SPM-ME用于测定土壤间隙水中自由溶解态憎水性有机污染物的可行性。结果表明,菲在该SPE-ME装置与水相间的平衡可在6h内达到,并且随着装置中三油酸甘油酯含量的增加,单元SPE-ME对于菲的富集系数也相应增加。该装置对土壤间隙水中菲的富集在10d内能达到平衡,整个过程主要受菲从土壤向间隙水的传质控制。该装置测得间隙水中菲的浓度与实际测得间隙水浓度十分吻合,而由传统的相平衡分配法计算所得间隙水浓度则高出实测值4～5倍。同时,该装置对体系中污染物的耗竭小于体系中污染物总量的1%。因此,SPE-ME是一种准确、有效、非耗竭式的微萃取技术。     

苏北泥质海岸主要防护林树种生长特性

以苏北泥质海岸主要造林树种杨树(72杨)、水杉和银杏为研究对象,在标准地调查的基础上,伐倒17株标准木,称其各器官的生物量,并根据树干解析法对其生长特性进行研究。结果表明:杨树生长速生期为6-11 a,早于水杉的16-21a,银杏在0-10 a内生长缓慢。宽冠型树种树冠在成熟龄后,仍有缓慢生长,而窄冠型树种则保持稳定。株行距越近于正方形越有利于宽冠型树种的生长,在胸径、生物量生长速度方面,林农复合明显快于片林。     

不同饵料对点带石斑鱼幼鱼生长、营养成分及组织消化酶活性的影响

将点带石斑鱼幼鱼(15±0.5) g,随机分为3组,每组投喂不同饵料,分别为鱼肉组、配合饲料组和混合饵料组(小杂鱼和配合饲料交替投喂),每组3个重复,养殖6周后测定各组幼鱼生长指标、全鱼营养成分、肠胃消化酶活性及肝脏磷酸酶活性以研究这3种饵料对点带石斑鱼幼鱼生长、消化功能及全鱼营养成分的影响。结果表明:鱼肉组和混合饵料组的相对增重率和特定生长率均显著高于配合饲料组(P<0.05)。肠、胃蛋白酶活性呈现鱼肉组>混合饵料组>配合饲料组的趋势且差异显著(P<0.05),肠淀粉酶活性趋势相反且差异显著(P<0.05);各组肠、胃脂肪酶活性之间没有显著差异(P>0.05);鱼肉组肝脏碱性磷酸酶活性显著高于配合饲料组(P<0.05),鱼肉肝脏组酸性磷酸酶活性显著高于混合饵料组和配合饲料组(P<0.05)。各组全鱼水分和灰分含量没有显著差异(P>0.05),粗蛋白含量为鱼肉组>混合饵料组>配合饲料组且差异显著(P<0.05);粗脂肪含量趋势相反,为鱼肉组<混合饵料组<配合饲料组且差异显著(P<0.05)。因此,小杂鱼在各方面都要优于配合饲料,交替投喂小杂鱼和配合饲料是一种较好的投喂方式。     

PGPR and entomopathogenic fungus bioformulation for the synchronous management of leaffolder pest and sheath blight disease of rice

BACKGROUND: The biological control of plant pests and diseases using a single organism has been reported to give inconsistent and poor performance. To improve the efficacy, bioformulations were developed possessing mixtures of bioagents. RESULTS: Bioformulations combining Pseudomonas fluorescens Migula strains Pf1 and AH1 and Beauveria bassiana (Balsamo) Vuill. isolate B2 were developed and tested for their efficacy against leaffolder pest and sheath blight disease on rice under glasshouse and field conditions. The combination of Pf1, AH1 and B2 effectively reduced the incidence of leaffolder insect and sheath blight disease on rice compared with other treatments. An in vitro assay of leaffolder preference to rice leaf tissues treated with Pf1 + AH1 + B2 biformulation showed variation from normal growth and development of leaffolder larvae. Plants treated with the Pf1 + AH1 + B2 combination showed a greater accumulation of enzymes, lipoxygenase and chitinase activity against leaffolder insect compared with other treatments. Similarly, the plants showed a higher accumulation of defence enzymes, peroxidase and polyphenol oxidase activity against sheath blight pathogen in Pf1 + AH1 + B2 treatment compared with the untreated control. The bioformulation mixture attracted the natural enemy population of leaffolder under field conditions. In addition, a significant increase in rice grain yield was observed in Pf1 + AH1 + B2 treatment compared with the untreated control. CONCLUSION: The combination of P. fluorescens strains and B. bassiana isolate effectively reduced the incidence of leaffolder insect and sheath blight disease on rice plants and showed the possibility of controlling both pest and disease using a single bioformulation. Copyright © 2010 Society of Chemical Industry