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The Comparison of Rotenone and an Environmentally Safe Insecticide (Azadirachtin) on Cultured Cell Respiration  [cached]
A Salehzadeh,R Abbasalipour
Journal of Research in Health Sciences , 2011,
Abstract: Background: Both azadirachtin and rotenone, two botanical pesticides have shown inhibit the growth of cultured insect cells. The inhibitory effect of rotenone on cell growth is through disruption of electron transport chain, but exact mechanism of effect of azadirachtin on growth of cell is unknown. This study was carried out to compare the effect of these phytochemical on oxygen consumption by cultured cells. Methods: Electron transport and oxygen uptake were measured using the oxygen electrode, which continuously determines the concentration of oxygen in solution. Rotenone was used as a positive control to investigate if azadirachtin had its effect on respiration of the cells. Estimates of oxygen uptake for Sf9 and C6/36 were done at 30 °C and for L929 at 37 °C. Results: Preliminary results indicated that concentration of 104 M of azadirachtin had the maximum effect on cell respiration. Also rotenone in concentration of 10-8 M reduced the cell respiration by 50%. However using purified mitochondria, the effect of azadirachtin on respiration rate was not significant. Conclusion: Interestingly in present test, both azadirachtin and rotenone could reduce the total oxygen consumption. Azadirachtin had only a minor effect on the respiration rate in both mammalian and insect cultured cells and there was only a slight differen
Efeito repelente de azadiractina e óleos essenciais sobre Aphis gossypii Glover (Hemiptera: Aphididae) em algodoeiro Repellent effect of azadirachtin and essential oils on Aphis gossypii Glover (Hemiptera: Aphididae) in cotton plants
Lígia Helena de Andrade,José Vargas de Oliveira,Iracilda Maria de Moura Lima,Mauricéa Fidelis de Santana
Revista Ciência Agron?mica , 2013,
Abstract: A repelência de inseticidas botanicos tem se destacado como uma tática promissora no controle alternativo de pragas agrícolas e urbanas, podendo ser um dos componentes do manejo integrado de pragas. Objetivou-se com este trabalho identificar a repelência de inseticidas botanicos sobre fêmeas ápteras de Aphis gossypii Glover. Testes com chance de escolha foram realizados com discos de folha de algodoeiro, imersos nas caldas dos inseticidas e testemunha (água destilada com DMSO a 2%). Utilizou-se azadirachtina (0,075%) e os óleos essenciais de Piper hispidinervum CDC, P. aduncum L., Cymbopogon winterianus (L.), C. citratus (D.C.) Stapf, Foeniculum vulgare Mill, Syzygium aromaticum (L.) Merrill e Perry, Cinnamomum zeylanicum Blume, Schinus terebinthifolius Raddi e Chenopodium ambrosioides L. na concentra o de 0,05%. C. citratus, C. winterianus, P. aduncum, S. terebinthifolius, azadirachtina e C. zeylanicum apresentaram os maiores percentuais de repelência, 100; 84; 66,67; 64; 60,87 e 48% respectivamente e reduziram a produ o de ninfas em 100; 92; 42,9; 87,5; 80,65 e 89,74%, apresentando resultados significativos pelo teste do χ2 ao nível de 10% de probabilidade. Nos testes com F. vulgare (χ2 = 3,66, P = 0,05) as fêmeas de A. gossypii foram atraídas significativamente para os discos tratados e ocorreu um aumento na produ o de ninfas nos resultados obtidos para F. vulgare (χ2 = 5,87, P = 0,02) e C. ambrosioides (χ2 = 14,31, P = 0,001). The repellence of botanical insecticides has emerged as a promising technique in the alternative control of urban and agricultural pests, being seen as one component of integrated pest management. The aim of this work was to identify the repellence of botanical insecticides on apterous females of Aphis gossypii Glover. Random-choice tests were carried out with discs from the leaves of cotton plants immersed in insecticide solution and in a control (distilled water with 2% DMSO). Azadirachtin was used (0.075%) and the essential oils of Piper hispidinervum CDC, P. aduncum L., Cymbopogon winterianus (L.), C. citratus (DC) Stapf, Foeniculum vulgare Mill, Syzygium aromaticum (L.) Merrill and Perry, Cinnamomum zeylanicum Blume, Schinus terebinthifolius Raddi and Chenopodium ambrosioides L. at a concentration of 0.05%. C. citratus, C. winterianus, P. aduncum, S. terebinthifolius, azadirachtin and C. zeylanicum showed the highest percentage of repellence, 100, 84, 66.67, 64, 60.87 and 48% respectively, and reduced nymph production by 100, 92, 42.9, 87.5, 80.65 and 89, 74%, with significant results from the χ2 test at 10% probabilit
Binding studies of paeonolum with bovine serum albumin using spectroscopic methods  [PDF]
Chang-yun Chen,Xiao-tian Gu,Jia-hong Zhou
Spectroscopy: An International Journal , 2007, DOI: 10.1155/2007/131582
Abstract: Fluorescence and UV spectroscopic techniques were used to investigate the interaction of Paeonolum, one of the major bioactive components isolated from the bark of peony plant, with bovine serum albumin (BSA). Results obtained reveal that a binding interaction occurs between paeonolum and BSA under physiological conditions, and the interaction can quench the fluorescence of BSA originating from the complex formation between paeonolum and BSA. In addition, according to the thermodynamics parameters of this interaction process, it appears that this binding interaction is mainly hydrophobic in nature.
Effect of azadirachtin and dihydro azadirachtin on invitro acquisition of rice tungro viruses  [cached]
C.N. BIJU, F.R. NIAZI and JASVIR SINGH
Indian Phytopathology , 2012,
Abstract: Two new neem oil formulations of azadirachtin (AZA) and dihydro azadirachtin (DHA) were tested in membrane feeding system either by mixing or spraying the membranes to investigate their effect on survival and feeding behaviour of green leafhopper (Nephotettix virescens Distant) and also on in vitro acquisition of rice tungro viruses. Although both the formulations
Biophysical Characterization of α-Synuclein and Rotenone Interaction  [PDF]
Blanca A. Silva,ól?f Einarsdóttir,Anthony L. Fink,Vladimir N. Uversky
Biomolecules , 2013, DOI: 10.3390/biom3030703
Abstract: Previous studies revealed that pesticides interact with α-synuclein and accelerate the rate of fibrillation. These results are consistent with the prevailing hypothesis that the direct interaction of α-synuclein with pesticides is one of many suspected factors leading to α-synuclein fibrillation and ultimately to Parkinson’s disease. In this study, the biophysical properties and fibrillation kinetics of α-synuclein in the presence of rotenone were investigated and, more specifically, the effects of rotenone on the early-stage misfolded forms of α-synuclein were considered. The thioflavine T (ThT) fluorescence assay studies provide evidence that early-phase misfolded α-synuclein forms are affected by rotenone and that the fibrillation process is accelerated. Further characterization by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) shows that rotenone increases the amount of ordered secondary structure in this intrinsically disordered protein. Morphological characterization by transmission electron microscopy (TEM) and atomic force microscopy (AFM) provide visualization of the differences in the aggregated α-synuclein species developing during the early kinetics of the fibrillation process in the absence and presence of rotenone. We believe that these data provide useful information for a better understanding of the molecular basis of rotenone-induced misfolding and aggregation of α-synuclein.
The Optimization of Ultrasonic Wave Extraction and Vacuum Liquid Chromatography for Isolation of Destruxins
Qiongbo Hu,Shunxiang Ren,Di Xu,Shuyan Liu
Research Journal of Biological Sciences , 2012,
Abstract: Destruxins, a family of cyclic peptide mycotoxins, have been being paid more and more attention for their multiple bioactivities such as insecticide, antivirus and immunomodulation. In order to decrease the consumption of solvents and time to isolate and purify destruxins A and B (DA and DB), Ultrasonic Wave Extraction (UWV) and Vacuum Liquid Chromatography (VLC) were employed. Under the optimal conditions of pH 4-5, solvent (dichloromethane/ethyl acetate, v v 1 = 1/1)/broth (v v 1) between 1-1.5 and extracted time in 45-90 min, UWV gave an excellent recovery (extracting efficiency > 90%). Meanwhile, in the VCL experiment, the gradient of hexane/acetone 100 /0-93/7 as eluant could isolate DA and DB clearly. However, the eluants of dichloromethane/methanol and hexane/ethyl acetate were not as good as hexane/acetone.
The Optimization of Ultrasonic Wave Extraction and Vacuum Liquid Chromatography for Isolation of Destruxins
Qiongbo Hu,Shunxiang Ren,Di Xu,Shuyan Liu
Research Journal of Biological Sciences , 2007,
Abstract: Destruxins, a family of cyclic peptide mycotoxins, have been being paid more and more attention for their multiple bioactivities such as insecticide, antivirus and immunomodulation. In order to decrease the consumption of solvents and time to isolate and purify destruxins A and B (DA and DB), Ultrasonic Wave Extraction (UWV) and Vacuum Liquid Chromatography (VLC) were employed. Under the optimal conditions of pH 4-5, solvent (dichloromethane/ethyl acetate, v v-1 = 1/1)/broth (v v-1) between 1-1.5 and extracted time in 45-90 min, UWV gave an excellent recovery (extracting efficiency > 90%). Meanwhile, in the VCL experiment, the gradient of hexane/acetone 100 /0-93/7 as eluant could isolate DA and DB clearly. However, the eluants of dichloromethane/methanol and hexane/ethyl acetate were not as good as hexane/acetone.
Effects of azadirachtin on Rhodnius prolixus: immunity and trypanosoma interaction
Azambuja, Patricia de;Garcia, Eloi S.;
Memórias do Instituto Oswaldo Cruz , 1992, DOI: 10.1590/S0074-02761992000900009
Abstract: the effects of azadirachtin, a tetranortriterpenoid from the neem tree aradirachta indica j. on both immunity and trypanosoma cruzi interaction within rhodniusprolixus and other triatomines, were presented given through a blood meal, azadirachtin affected the immune reactivity as shown by a significant reduction in numbers of hemocytes and consequently nodule formation follwing challenge with enterobacter cloacae ?12, reduction in ability to produce antibacterial activities in the hemolymph when injected with bacteria, and decreased ability to destroy the infection caused by inoculation of e. cloacae cells. a single dose of azadirachtin was able to block the development of t. cruzi in r. prolixus if given through the meal at different intervals, together with, before or after parasite infection. similary, these results were observed with different triatomine species and different strains of t. cruzi. azadirachtin induced a permanent resistance of the vector against reinfection with t. cruzi. the significance of these data is discussed in relation to the general mode of azadirachtin action in insects.
Effects of azadirachtin in Rhodnius prolixus: data and hypotheses
Garcia, E. S.;Gonzales, M. S.;Azambuja, P.;
Memórias do Instituto Oswaldo Cruz , 1991, DOI: 10.1590/S0074-02761991000600025
Abstract: the effects of azadirachtin a, a tetranortriterpenoid from the neem tree azadirachta indica j., on both development and interaction between trypanosoma cruzi, the causative agent of chagas' disease, and its vector rhodnius prolixus were studied. given through a blood meal, a dose-rsponse relationship of azadirachtin was established using antifeedant effect and ecdysis inhibition as effective parameters. a singlo dose of azadirachtin a was able to block the onset of mitosis in the epidermis and ecdysteroid titers in the hemnolymph, determined by radioimmuneassay, were too low for an induction of ecadysis. the survival of t. cruzi was also studied in r. prolixus treated with the drug. if the trypomastigotes were fed in presence of azadirachtin a the number of parasites drastically decreased. if the drug was applied after infection of the bug with t. cruzi, the parasite was still abolished from the gut. if the insect was pretreated with azadirachtin a before infection the same observation was obtained. a single dose of azadirachtin a was enough for a permanent resistance of the insect host against its reinfection with t. cruzi and for blocking the ecdysis for a long time. the effects of azadirachtin a on the hormonal balance of the host and growth inhibition of the parasite will be discussed on the basis of the present results.
Common Pesticide Rotenone Interference with Neuronal Transmission in Hippocampus
American Journal of Biomedical Engineering , 2012, DOI: 10.5923/j.ajbe.20120206.01
Abstract: Rotenone is a pesticide and piscicide, which causes behavioral and biochemical changes in rats that closely resemble PD symptoms in humans. Rotenone is a naturally occurring retinoid plant extract derived from the roots of certain tropical and subtropical legume plants and interferes with energy production in the cell. Rotenone is highly lipophilic, so it can easily cross the blood brain barrier and cellular membrane for intracellular entry.It is known that this pesticide causes superoxide release and results in decreased energy production by inhibiting electron transport chain of mitochondria from NADH ubiquinone reductaseand may lead to neuronal death. The object of the current research is to investigate the effect of rotenone on synaptic transmission in hippocampus, especially on glutamatergic transmission for a brief exposure time. For this purpose, hippocampal CA1 pyramidal neuronal response upon low frequency stimulation of Schaffer collateral (0.1 Hz) was recorded by the patch clamp tight-seal whole cell recording technique. Different rotenone concentrations were tested on total glutamate current; it was observed that the rotenone effect on the amplitude of glutamatergic currents is dependent on its concentration. To eliminate the rotenone induced cytoplasmic effects, ATP was excluded from the intracellular solution in experiments. Our experimental results show that the drug acutely and dose-dependently attenuates the currents that are mediated by glutamate, via a direct effect on cell membrane glutamate receptors.
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