Four microorganisms, Pseudomonas sp. (ER2), Aspergillus niger (ER6), Cladosporium herbarum (ER4) and Penicilluim sp. (ER3), were isolated from cucumber leaves previously treated with metalaxyl using enrichment...Four microorganisms, Pseudomonas sp. (ER2), Aspergillus niger (ER6), Cladosporium herbarum (ER4) and Penicilluim sp. (ER3), were isolated from cucumber leaves previously treated with metalaxyl using enrichment technique. These isolates were evaluated for detoxification of metalaxyl at the recommended dose level in aquatic system. The effect of pH and temperature on the growth ability of the tested isolates was also investigated by measuring the intracellular protein and mycelia dry weight for bacterial and fungal isolates, respectively. Moreover, the toxicity of metalaxyl after 28 d of treatment with the tested isolates was evaluated to confirm the complete removal of any toxic materials (metalaxyl and its metabolites). The results showed that the optimum degree pH for the growth of metalaxyl degrading isolates (bacterial and fungal isolates) was 7. The temperature 30℃ appeared to be the optimum degree for the growth of either fungal or bacterial isolates. The results showed that Pseudomonas sp. (ER2) was the most effective isolate in metalaxyl degradation followed by Aspergillus niger (ER6), Cladosporium herbarum (ER4) and Penicilluim sp. (ER3), respectively. There is no toxicity of metalaxyl detected in the supematant after 28 d of treatment with Pseudomonas sp. (ER2). The results suggest that bioremediation by Pseudomonas sp. (ER2) isolate was considered to be effective method for detoxification of metalaxyl in aqueous media.展开更多
This study was mainly made on the role of energy revisers in cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) countered with imidacloprid and thiametoxam. We measured used energy, available energy and the...This study was mainly made on the role of energy revisers in cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) countered with imidacloprid and thiametoxam. We measured used energy, available energy and the content of total energy in three strains of cotton aphid which were from very resistant to neonicotinoid, sup to semi-sensitive and sensitive speccies, respectively. It was observed changes in energy resources rate in all of the aphid strains at which each substrate was metabolized under stress. Our findings indicated among energy sources, total lipid in susceptible strain was increased in counter of spraying and it was decreased in resistance and semi sensitive strains. Whereas, total protein was decreased in all of the strains encountering with neonicotiniod stress. Total glycogen was increased significantly in different aphid strains and sugar was decreased in countered of spraying.展开更多
In this study, the susceptibility of three populations of cotton aphid, Aph& gossypii Glover (Hemiptera:Aphididae) was assayed to imidacloprid (35SC) and thiametoxam (50WG). The involvement of metabolic enzyme...In this study, the susceptibility of three populations of cotton aphid, Aph& gossypii Glover (Hemiptera:Aphididae) was assayed to imidacloprid (35SC) and thiametoxam (50WG). The involvement of metabolic enzymes in the resistance strain of cotton aphid to the neonicotinoids was determined by the biochemical biomarkers and the resistance mechanism was determined as CaE. In another study, three different bioassay experiments were designed for detecting the susceptibility of cotton aphid to imidacloprid and thiametoxam and the effect of these two insecticides on the enzymatic activity of cotton aphid was assessed in the adult aphids treated with three different bioassay methods using a modified version of the FAO dip test, residue bioassay procedure and starvation method. Our findings suggested that the type of bioassay methods is very important when aphids' populations assess for the resistance against the neonicotinod insecticides. It has shown the starvation method is the most reliable method compared with other methods.展开更多
Three populations of Aphis gossypii of distinct susceptibility to neonicotinoids show differences in the accumulation and mobilization of energy reserves, what may allow the production of their defensive tools against...Three populations of Aphis gossypii of distinct susceptibility to neonicotinoids show differences in the accumulation and mobilization of energy reserves, what may allow the production of their defensive tools against two neonicotinoid insecticides without impairing their reproductive performance. Bioassays were also carried out for these aphid populations. According to the results obtained, the Ag-R population showed resistant rate significantly higher than the other two populations. Levels of some biochemical characteristics were determined in the resistant, susceptible and semi susceptible populations of cotton aphid. The results obtained in the assays with biochemical parameters indicated significant differences in activity among the populations, with higher activity in using glycogen in the Ag-R population. The inverse activity trends oft (generation time) and DT (doubling time) in both resistant and susceptible populations, one showing fitness disadvantage without insecticide exposure and the other not showing it, may underlay the mitigation of insecticide resistance physiological costs observed in the Ag-R population.展开更多
A study on the structure-activty relationship between (Z)-hexadec-9-enal (Z-9-16:Ald) and its analog was conducted by comparing the structures of the sex pheromone of cotton bollworm, Helicoverpa armigera (Hübner...A study on the structure-activty relationship between (Z)-hexadec-9-enal (Z-9-16:Ald) and its analog was conducted by comparing the structures of the sex pheromone of cotton bollworm, Helicoverpa armigera (Hübner) with its fluorinated analog using computer molecular fitting. It is demonstrated that the structure of analog substituting for hydrogen atom on the terminal carbon atom is similar to Z-9-16:Ald. The EAG result showed that there is no signifi- cant difference in activities between Z-9-16:Ald and its fluorinated analog synthesized.展开更多
Alibrary of novel spiro[pyrazole-4,5′-isoxazoline]-5-one derivatives were designed and synthesized using a concise and efficient one-pot reaction protocol through 1,3-dipolar cycloaddition between 4-benzylidene-3-met...Alibrary of novel spiro[pyrazole-4,5′-isoxazoline]-5-one derivatives were designed and synthesized using a concise and efficient one-pot reaction protocol through 1,3-dipolar cycloaddition between 4-benzylidene-3-methyl-1-phenyl-^(1)H-pyrazol-5(4H)-one and chlorooximes.The synthesized derivatives were elucidated and characterized based on their spectroscopic data,including infrared spectrometry(IR),^(1)H NMR,^(13)C NMR,and elemental and mass spectral analysis.The synthesized compounds were evaluated for their antitumor inhibition potency against four human cancer cell lines,including human prostatic adenocarcinoma(PC3),human colorectal carcinoma(HCT116),human liver hepatocellular carcinoma(HepG2)and breast adenocarcinoma(MCF7).The outcomes were compared with the standard reference drug Doxorubicin.Among the synthesized chlorooximes,compounds 6d and 6e were the most active compounds on all cell lines.The spiro[pyrazole-4,5′-isoxazoline]-5-one derivatives 7a and 7c were active on the HepG2 liver cancer cell line.In comparison,compounds 7f and 7g were moderately active on the MCF7 cell line.The structure-activity relationship was explored for the synthesized compounds.Besides,in silico analysis of physicochemical,adsorption,distribution,metabolism,excretion and toxicity(ADMET)properties were done to determine the potential capacity of drug candidates.Molecular docking study onto the epidermal growth factor(EGF)tyrosine kinase receptor(3POZ)was done for the most active compounds to validate the reliability of in vitro anticancer screenings.展开更多
文摘Four microorganisms, Pseudomonas sp. (ER2), Aspergillus niger (ER6), Cladosporium herbarum (ER4) and Penicilluim sp. (ER3), were isolated from cucumber leaves previously treated with metalaxyl using enrichment technique. These isolates were evaluated for detoxification of metalaxyl at the recommended dose level in aquatic system. The effect of pH and temperature on the growth ability of the tested isolates was also investigated by measuring the intracellular protein and mycelia dry weight for bacterial and fungal isolates, respectively. Moreover, the toxicity of metalaxyl after 28 d of treatment with the tested isolates was evaluated to confirm the complete removal of any toxic materials (metalaxyl and its metabolites). The results showed that the optimum degree pH for the growth of metalaxyl degrading isolates (bacterial and fungal isolates) was 7. The temperature 30℃ appeared to be the optimum degree for the growth of either fungal or bacterial isolates. The results showed that Pseudomonas sp. (ER2) was the most effective isolate in metalaxyl degradation followed by Aspergillus niger (ER6), Cladosporium herbarum (ER4) and Penicilluim sp. (ER3), respectively. There is no toxicity of metalaxyl detected in the supematant after 28 d of treatment with Pseudomonas sp. (ER2). The results suggest that bioremediation by Pseudomonas sp. (ER2) isolate was considered to be effective method for detoxification of metalaxyl in aqueous media.
文摘This study was mainly made on the role of energy revisers in cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) countered with imidacloprid and thiametoxam. We measured used energy, available energy and the content of total energy in three strains of cotton aphid which were from very resistant to neonicotinoid, sup to semi-sensitive and sensitive speccies, respectively. It was observed changes in energy resources rate in all of the aphid strains at which each substrate was metabolized under stress. Our findings indicated among energy sources, total lipid in susceptible strain was increased in counter of spraying and it was decreased in resistance and semi sensitive strains. Whereas, total protein was decreased in all of the strains encountering with neonicotiniod stress. Total glycogen was increased significantly in different aphid strains and sugar was decreased in countered of spraying.
文摘In this study, the susceptibility of three populations of cotton aphid, Aph& gossypii Glover (Hemiptera:Aphididae) was assayed to imidacloprid (35SC) and thiametoxam (50WG). The involvement of metabolic enzymes in the resistance strain of cotton aphid to the neonicotinoids was determined by the biochemical biomarkers and the resistance mechanism was determined as CaE. In another study, three different bioassay experiments were designed for detecting the susceptibility of cotton aphid to imidacloprid and thiametoxam and the effect of these two insecticides on the enzymatic activity of cotton aphid was assessed in the adult aphids treated with three different bioassay methods using a modified version of the FAO dip test, residue bioassay procedure and starvation method. Our findings suggested that the type of bioassay methods is very important when aphids' populations assess for the resistance against the neonicotinod insecticides. It has shown the starvation method is the most reliable method compared with other methods.
文摘Three populations of Aphis gossypii of distinct susceptibility to neonicotinoids show differences in the accumulation and mobilization of energy reserves, what may allow the production of their defensive tools against two neonicotinoid insecticides without impairing their reproductive performance. Bioassays were also carried out for these aphid populations. According to the results obtained, the Ag-R population showed resistant rate significantly higher than the other two populations. Levels of some biochemical characteristics were determined in the resistant, susceptible and semi susceptible populations of cotton aphid. The results obtained in the assays with biochemical parameters indicated significant differences in activity among the populations, with higher activity in using glycogen in the Ag-R population. The inverse activity trends oft (generation time) and DT (doubling time) in both resistant and susceptible populations, one showing fitness disadvantage without insecticide exposure and the other not showing it, may underlay the mitigation of insecticide resistance physiological costs observed in the Ag-R population.
文摘A study on the structure-activty relationship between (Z)-hexadec-9-enal (Z-9-16:Ald) and its analog was conducted by comparing the structures of the sex pheromone of cotton bollworm, Helicoverpa armigera (Hübner) with its fluorinated analog using computer molecular fitting. It is demonstrated that the structure of analog substituting for hydrogen atom on the terminal carbon atom is similar to Z-9-16:Ald. The EAG result showed that there is no signifi- cant difference in activities between Z-9-16:Ald and its fluorinated analog synthesized.
基金supported by the Fund of National Research Centre,Egypt.
文摘Alibrary of novel spiro[pyrazole-4,5′-isoxazoline]-5-one derivatives were designed and synthesized using a concise and efficient one-pot reaction protocol through 1,3-dipolar cycloaddition between 4-benzylidene-3-methyl-1-phenyl-^(1)H-pyrazol-5(4H)-one and chlorooximes.The synthesized derivatives were elucidated and characterized based on their spectroscopic data,including infrared spectrometry(IR),^(1)H NMR,^(13)C NMR,and elemental and mass spectral analysis.The synthesized compounds were evaluated for their antitumor inhibition potency against four human cancer cell lines,including human prostatic adenocarcinoma(PC3),human colorectal carcinoma(HCT116),human liver hepatocellular carcinoma(HepG2)and breast adenocarcinoma(MCF7).The outcomes were compared with the standard reference drug Doxorubicin.Among the synthesized chlorooximes,compounds 6d and 6e were the most active compounds on all cell lines.The spiro[pyrazole-4,5′-isoxazoline]-5-one derivatives 7a and 7c were active on the HepG2 liver cancer cell line.In comparison,compounds 7f and 7g were moderately active on the MCF7 cell line.The structure-activity relationship was explored for the synthesized compounds.Besides,in silico analysis of physicochemical,adsorption,distribution,metabolism,excretion and toxicity(ADMET)properties were done to determine the potential capacity of drug candidates.Molecular docking study onto the epidermal growth factor(EGF)tyrosine kinase receptor(3POZ)was done for the most active compounds to validate the reliability of in vitro anticancer screenings.