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31.
The effect of botanical insecticides and bacterial toxins on gut enzyme activity of larvae of the rice leaffolderCnaphalocrocis medinalis (Guenée) (Insecta: Lepidoptera: Pyralidae) was investigated. Gut enzyme activities were affected by botanical insecticides
and bacterial toxin individually and in combination. When fed a diet of rice leaves treated with botanical insecticides and
bacterial toxins, in bioassays the activities of gut tissue enzymes — acid phosphatases (ACP), alkaline phosphatases (ALP)
and adenosine triphosphatases (ATPase) — of rice leaffolder larvae were affected. When combined, the effect was more severe
at a low concentration. Larvae that were chronically exposed to botanical insecticides and bacterial toxins showed a reduction
in weight (59–89%) and exhibited a significant reduction in ACP, ALP and ATPase activities. The combination ofBacillus thuringiensis kurstaki and botanical insecticides caused a decrease of twofold in enzyme activity even at reduced concentration. A synergistic effect
was found when botanical insecticides and bacterial toxins were combined at low doses. These effects were most pronounced
in early instars. Clear dose-response relationships were established with respect to enzyme activity. In conclusion: (i) biopesticides
are relatively safe and biodegradable; (ii) a synergistic effect of botanical insecticides and bacterial toxins was found;
(iii) less expensive, readily available and naturally occurring biopesticides could be an alternative for organic and inorganic
pesticides in controlling RLF.
http://www.phytoparasitica.org posting Sept. 28, 2004. 相似文献
32.
【目的】利用原核表达小菜蛾(Plutella xyllostella)中肠膜结合碱性磷酸酯酶(membrane-bound alkaline phosphatase,mALP)并经Ligand blot验证其具有与Cry1Ac毒素结合的能力;通过同源建模和分子对接研究Cry1Ac-mALP的结合模式,预测毒素和受体结合区域及关键氨基酸位点(热点残基),为了解毒素-受体互作机制及分子改造增强Cry毒素活性的研究打下基础。【方法】针对小菜蛾mALP全长设计引物,并以小菜蛾c DNA为模板扩增mALP基因,双酶切后用T4连接酶连接至pET-26b原核表达载体,将构建的pET-26b-mALP载体转化Trans1-T1克隆感受态,挑取克隆并提取质粒后进行PCR、双酶切和测序验证,将验证无误的重组质粒转化E.coliBL21(DE3)表达感受态细胞,进行诱导表达。将诱导表达后的mALP转至PVDF膜上,通过Western blot和Ligand blot分别验证mALP是否成功表达以及是否具有与Cry1Ac毒素结合的能力。对mALP进行同源建模、分子动力学模拟以及模型评价,获得的mALP最佳三维结构与Cry1Ac毒素利用Patch DOCK和Fire Dock程序进行分子对接试验,对确定的最佳毒素-受体复合物进行结合区域和结合氨基酸位点分析,并通过计算机辅助的丙氨酸突变扫描试验确定毒素和受体参与的关键氨基酸残基。【结果】扩增出小菜蛾mALP基因并克隆至pET-26b原核表达载体,转化E.coli BL21(DE3)表达感受态后挑取阳性克隆提取质粒后进行PCR、双酶切和测序均显示构建正确。通过原核表达和Western blot验证成功表达了mALP蛋白,并经Ligand blot试验证实了原核表达的mALP具有和Cry1Ac毒素结合的能力。利用同源建模成功获得了mALP的三维结构,通过Patch DOCK和Fire Dock分子对接程序,获得毒素和受体的对接复合物,通过溶剂可及表面积变化计算和Ligplot分析,确定毒素结构域Ⅱ和结构域Ⅲ均参与了受体结合,并且毒素和受体均以疏水结合和氢键结合模式参与结合,最后通过热点残基预测发现Cry1Ac毒素和mALP中分别有3个氨基酸残基(376ASN、443SER和486SER)和4个氨基酸残基(452ARG、499THR、502TYR和513TYR)是参与互作的关键氨基酸位点。【结论】经原核表达的小菜蛾mALP同样具有与Cry1Ac毒素结合的能力,并利用分子模拟技术预测了小菜蛾mALP三维结构及与Cry1Ac毒素结合模式。 相似文献
33.
亚硝酸盐对茂名海域文昌鱼生长及磷酸酶的影响 总被引：2，自引：0，他引：2
研究了文昌鱼对亚硝酸盐(NO2-)的耐受极限以及在NO2-胁迫条件下文昌鱼的体重及磷酸酶的变化。结果表明,文昌鱼在(25±1)℃温度条件下耐受NO2-的96h的LC50为262.98mg/L。在水体NO2-不超过0.34mg/L时文昌鱼酸性磷酸酶(ACP)较对照组无显著变化(P>0.05),在浓度为0.24mg/L时碱性磷酸酶(ALP)受显著促进作用(P<0.05);当水体NO2-大于12.07mg/L时,文昌鱼ALP和(ACP)活性均随水体中NO2-浓度的增加受到显著(P<0.05)的抑制作用。水体浓度达33.44mg/L时,文昌鱼体重与对照组相比受抑制作用显著(P<0.05)。 相似文献
34.
研究了吡喹酮不同给药方式对鲫(Carassius auratus)的急性和亚急性毒性试验。急性毒性试验结果显示:浸泡时吡喹酮对鲫的24、48、96 h的半致死浓度(LC50)分别为54.80 mg/L、51.07 mg/L、50.78 mg/L;按每千克鱼体重10 g吡喹酮的剂量灌胃时,96 h未见明显中毒症状。亚急性试验结果显示:在不同的给药方式下,与对照组相比,低浓度的吡喹酮未对碱性磷酸酶(ALP)、超氧化物歧化酶(SOD)和谷丙转氨酶(ALT)的活性造成显著影响(P>0.05);随着试验时间的延长,较高浓度的吡喹酮使SOD活性先升高后降低,ALT活性显著(P<0.05)或极显著高于对照组(P<0.01)。 相似文献
35.
The effect of Bacillus thuringiensis (B.t.) inoculation on plant growth and on the intra- and extraradical mycorrhizal development of lettuce roots colonized by Glomus mosseae or Glomus intraradices was examined in an inert, soil-less substrate. Histochemical determination of succinate dehydrogenase (SDH) and alkaline phosphatase (ALP) activities which indicate active fungal metabolism was carried out at two phosphorus (P) levels. The presence of B.t. increased extra- and intraradical colonization [measured as frequency (%F), intensity (%I) and percentage of arbuscules (%A)] for both arbuscular mycorrhizal fungi (AMF) rather than plant growth or nutrition regardless P level. Under the lowest level of P fertilization, B.t. enhanced to a similar extent the extra- and intraradical development of both endophytes, but the proportion of fungal tissue showing SDH or ALP was increased in G. intraradices-colonized plants. [SDH: 458% (M) and 512% (A); ALP: 358% (M) and 300% (A)]. P supply decreased G. intraradices colonization to a higher extent than G. mosseae. Nevertheless, the totality of G. intraradices structures developed in P-amended medium showed intraradical o extraradical activity, while in G. mosseae-colonized roots, SDH and ALP activities highly decreased relative to fungal tissue determined by TB staining as affected by P. Our results show that bacterial inoculation compensates the negative effect of P on the intraradical fungal growth and vitality. P amendment reduced in a higher extent G. intraradices infection intensity (non-vital and vital staining) and G. mosseae activity (ALP staining). Thus, big differences in the proportion of SDH-active infection showing ALP activity in mycelium developed by each endophyte were noted at the highest P level. Physiological plant parameters such as photosynthetic activity did not explain specific changes on each arbuscular-mycorrhizal fungus as affected by P or B.t. inoculation. The increased extraradical mycelium development and metabolic fungal activity as a result of B.t. inoculation positively affected N and P plant content and photosynthetic rate in G. intraradices-colonized plants under the lowest P conditions. In general, the increased metabolically active fungal biomass in co-inoculated plants was irrespective of P level and was not related to the P plant uptake from the inert soil-less substrate. These results show the bacterial effect increasing the physiological and metabolic status of AM endophytes, which not only confirms but also extends previous findings on arbuscular mycorrhizae-bacteria interactions. The present study emphasizes the ecological and practical importance of rhizosphere free-living bacteria as mycorrhizae-helper microorganisms. 相似文献
36.
肽聚糖制剂对南美白对虾体液免疫因子的影响 总被引：15，自引：4，他引：15
按一定梯度配制5种含不同水平肽聚糖制剂的饲料,投喂南美白对虾(Litopenaeus vannamei),35 d后取实验对虾血样,用于测定血清中酚氧化酶活力、磷酸酶活力、溶菌活力及超氧化物歧化酶活力.结果显示,饲料中肽聚糖质量分数为500×10-6的实验组,对虾血清中酚氧化酶活力最高,肽聚糖质量分数为2 500×10-6的实验组,对虾血清中酸性磷酸酶与碱性磷酸酶活力最高,肽聚糖对对虾的血清溶菌活力影响不明显(P>0.05).由此表明饲料中添加适量(质量分数500×10-6左右)的肽聚糖制剂可使对虾体液免疫因子总体活力达到较高水平,饲料中肽聚糖制剂含量过高对对虾非特异免疫力的作用效果反而不佳.南美白对虾血清中酚氧化酶活力对饲料中肽聚糖含量变化较敏感,可作为肽聚糖使用效果的评价指标之一. 相似文献
37.
将杂色鲍(Haliotis diversicolor)注射感染大肠杆菌(E.coli)和副溶血弧菌(Vibrio parahemolyticus),在感染后第4、8、12、24、48、96、192小时分别采集无细胞血淋巴,测定碱性磷酸酶(ALP)、酸性磷酸酶(ACP)和超氧化物岐化酶(SOD)的活力.结果表明,弧菌组ACP的活力在第24小时比对照组显著增高;弧菌组的ALP与对照组相比,在第8小时显著增高,第48小时极显著升高,第96小时显著下降.弧菌组的SOD活力在24小时与对照组相比显著降低.而大肠杆菌组ALP、ACP和SOD的活力跟对照组相比,各个时相均无显著差异.由此可见,杂色鲍对致病菌和非致病菌可能有着不同的免疫机制. 相似文献
38.
Clinical enzymology studies the enzyme activity in serum or other body fluids for the diagnosis, prognosis or monitoring of a variety of diseases. Clinical enzymology has greatly benefited from advances in technology and is now an integral part of laboratory analysis. However, to maximise the clinical benefits of serum enzyme measurement, clinicians and clinical pathologists must have a good understanding of the pathophysiology behind serum enzyme alterations. They must also be aware of the preanalytical and analytical factors that can affect the accuracy of serum enzyme activity measurement. This review article first covers the basic concepts of clinical enzymology and the general mechanisms related to serum enzyme alterations. Then, the review discusses the potential effects of various preanalytical and analytical factors on enzyme activity measurement. Lastly, it explores the pathophysiology and clinical use of various serum enzymes in canine and feline medicine. The present review article aims to be a comprehensive one-stop source for clinical pathologists and small animal practitioners. 相似文献
39.
Oxidative damage in bone and erythrocytes of suckling rats exposed to 2,4-dichlorophenoxyacetic acid
Afef TroudiMadiha Sefi Ibtissem Ben Amara Nejla SoudaniAhmed Hakim Khaled Mounir ZeghalTahia Boudawara Najiba Zeghal 《Pesticide biochemistry and physiology》2012,104(1):19-27
Nowadays, people’s exposure to pesticides such as 2,4-dichlorophenoxyacetic acid (2,4-D) is increasing continuously. This compound is suspected to produce in excess free radicals which have adverse effects on human health causing several cell alterations in the organism. The present study investigated oxidative stress in the bone and erythrocytes of suckling rats whose mothers were treated with 2,4-D. Experiments were carried out on adult Wistar rats given 600 mg/L of 2,4-D in their drinking water from the 14th day of pregnancy until day 14 after delivery. Exposing dams to 2,4-D caused disorders in the bone of their progeny. Indeed, it induced changes in bone mineralization, especially calcium and phosphorus levels. Moreover, total tartrate-resistant acid phosphatase, which reflected bone resorption, was enhanced while total alkaline phosphatase, which reflected bone formation, was reduced suggesting that this herbicide accelerated bone resorption. The impairment of bone function corresponded histologically.Rats exposed to 2,4-D showed in both bone and erythrocytes an increase in malondialdehyde, advanced oxidation protein products and protein carbonyl levels and a decrease in non-enzymatic (glutathione, non-protein thiol, and vitamin C) and enzymatic (superoxide dismutase, catalase, and glutathione peroxidase) antioxidant system. 相似文献
40.
Sipra Mohapatra Tapas Chakraborty Ashisa Kumar PrustyKundan Kumar K. Pani PrasadKedar Nath Mohanta 《Pesticide biochemistry and physiology》2012,104(1):28-37
Five experimental diets with various combinations of probiotics, namely T1 & T6 (basal feed (BF) without probiotics), T2 & T7 (BF + Bacillus subtilis + Lactococcus lactis), T3 & T8 (BF + L. lactis + Saccharomyces cerevisiae), T4 & T9 (BF + B. subtilis + S. cerevisiae) and T5 & T10 (BF + B. subtilis + L. lactis + S. cerevisiae) were fed to Labeo rohita fingerlings for 30 days. Treatment groups T1, T2, T3, T4 and T5 were exposed to Fenvalerate, at a concentration of 1.79 μg L−1. The SOD and CAT activity was significantly affected (P < 0.01) in fenvalerate treated groups. However, the supplementation of the three-probiotic mixture at equal concentration showed markedly reduced activity. Similarly, RBC, Hb, NBT, total protein and albumin values were reduced significantly (P < 0.01) in the fenvalerate exposed fish as compared to the probiotic supplemented fish. Fenvalerate exposure also showed increased serum ALP, ACP and Bilirubin values (P < 0.01) in comparison to the non-exposed fish. Histological observations of the gills, kidney and liver showed tissue degeneration after fenvalerate exposure, which however showed marked recovery on the three-probiotic mixture supplementation. Therefore, these results indicate that a mixture of multi-species probiotic supplementation in equal concentration acts beneficially in mitigating the stressful effects of fenvalerate. 相似文献