[ Objective] The paper was to prepare bifenthrin nanoemulsions, and to characterize its property. [ Method ] Oil in water type of bifenthrin nanoemul- sions was prepared using emulsion phase transition method at const...[ Objective] The paper was to prepare bifenthrin nanoemulsions, and to characterize its property. [ Method ] Oil in water type of bifenthrin nanoemul- sions was prepared using emulsion phase transition method at constant temperature of 25℃. The formation mechanism of nanoemulsions was investigated, and the property of bffenthrin nanoemulsions was characterized by dynamic light scattering（DIS）, transmission electron microscopy （TEM）, contact angle meter, interfa- cial tension meter and high performance liquid chromatogTaphy （HPLC）. [ Result ] Phase transition occurred during the formation progress of bifenthrin nanoemul- sions ; the particles of nancomulsions system was spherical, and the particle size was mainly distributed in the range of 25 -30 ran; the contact angle on paraffin was less than 90° with good wetting effect; the surface tension was less than 40 mN/m, and the emulsification effect was also good, so the utilization rate of bifenthrin nancomulsions was improved. HPLC results showed that bffenthrin was not easy to decompose or precipitate with good stability. [ Conclusion] The result provided basis for the preparation of new types of insecticides.展开更多
With the increasing use of synthetic pyrethroids （SPs）, the significance of ecological safety and health risk is an emerging concern, In this study, we evaluated the chronic aquatic toxicity of eis-bifenthrin （cis...With the increasing use of synthetic pyrethroids （SPs）, the significance of ecological safety and health risk is an emerging concern, In this study, we evaluated the chronic aquatic toxicity of eis-bifenthrin （cis-BF） in Daphnia magna and its cytotoxicity in Chinese hamster ovary （CHO） cells as well as human cervical carcinoma （Hela） ceils. Chronic aquatic toxicity tests showed that cis-BF could significantly affect the reproduction of D. magna. The lowest observed effective concentration and the non-observed effective concentration of cis-BF to D. magna were 0.02 and 0.01 μg/L, respectively, and the chronic value was 0.014 μg/L. The intrinsic rate of natural increase was significantly decreased （p 〈 0.05） to 0.02 μg/L. The cytotoxicity assay demonstrated that cis-BF decreased cell viability in CHO and Hela cells in a concentration- and time-dependent manner. The IC50 values for Hela and CHO cells were 4.0 × 10^-5 and 3.2 × 10^-5 mol/L, respectively. Together, these results indicated that cis-BF induced chronic toxicity in both aquatic invertebrate animals and mammalian cells. These findings assist in understanding the impact of SPs on health and environmental safety. Considering the wide spectrum of SPs, a more comprehensive understanding of the negative effects is indispensible for planning future application and regulation of these pesticides.展开更多
The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L r...The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L respectively. And the LOEC and NOEC of bifenthrin were 0.02 and 0.004 μg/L respectively. The recovery test of bifenthrin on Daphnia magna was presented. Daphnia magna(F 0 generation) were exposed during 21 d to different bifenthrin concentrations. Offspring(animals from the first and third brood: F 1(1st) and F 1(3rd), respectively) were transferred to a free pesticide medium during a 21 d recovery period. In this recovery study, survival, growth, reproduction(mean total young per female, onset of reproduction and number broods per female) and the intrinsic rate of natural increase (r) were assessed as parameters. Reproduction such as number of young per female as well as length was still reduced in F 1(1st) generation daphnids from parentals(F 0) exposed to the bifenthrin. However F 1(3rd) individuals from parentals exposed to pesticide concentrations were able to restore reproduction when a recovery period of 21 d was allowed, but the length of F 1(3rd) from parentals exposed to the 0.5 and 0.75 μg/L bifenthrin concentration was still significantly effected(P<0.05).展开更多
Bifenthrin（BF） is a pyrethroid insecticide that is widely used in agriculture, horticulture, and for residential purposes. However, few studies addressing the reproductive toxicity of BF on fishes are available. The...Bifenthrin（BF） is a pyrethroid insecticide that is widely used in agriculture, horticulture, and for residential purposes. However, few studies addressing the reproductive toxicity of BF on fishes are available. The present study was conducted to investigate the effects of BF on testicular development in Sebastiscus marmoratus and to gain insight into its mechanism. After exposure to 1, 10 and 100 ng/L BF for 50 days, there was a reduced number of mature sperm and an abundance of the late stages of spermatocysts in the testes. The levels of 17β-estradiol and testosterone were decreased significantly after BF exposure. The activity of caspase-3 was increased in a dosedependent manner after BF exposure, TUNEL assay indicated that BF exposure resulted in the occurrence of apoptosis in the testes, which might be main reason for the inhibition of spermatogenesis.展开更多
Bifenthrin is an insecticide which is used to control insects, mites, and ticks. It poses a solemn en-vironmental threat and health risk to living organisms. It may be bioaccumulated or biomagnified at different troph...Bifenthrin is an insecticide which is used to control insects, mites, and ticks. It poses a solemn en-vironmental threat and health risk to living organisms. It may be bioaccumulated or biomagnified at different trophic levels in the food chain by biota. Microbes are hidden creature of earth’s biodiversity. For isolation of bifenthrin degrading bacteria, rhizospheric soil samples of plants like Pisum sativum, Triticun aestvum, Chenopodium album were taken from tannery solid waste, Kasur, Pakistan. Enrichment culture techniques were used for the isolation of bacterial strains that showed luxurious growth on minimal growth media with bifenthrin dose was selected for biodegradation study. Bacteria were further screened out based on their morphological, biochemical parameters and degradation efficiency. Furthermore the effect of different growth factors like temperature, pH, inoculum concencentration, minimal inhibitory concentration of heavy metals and antibiotics were also studied. Bacterial strains of Xanthomonas and Bacillus sp. were identified as efficient degrading microbes. Maximum bifenthrin utilization were observed at 25°C (pH 7), with 500 μL inoculum of Bacillus sp., while Xanthomonas sp. gave optimm utilization at 30°C (pH 7) at the same inoculum volume of bacteria. The Rf values of Bacillus sp. and Xanthomonas sp. were 0.91 and 0.90 respectively, which indicated their potential to metabolize bifenthrin into nontoxic forms. These strains can be used to clean up the sites polluted with pesticides and tannery wastes when present in rhizosphere of plants.展开更多
Rhizodegradation is a process by which plant-supplied substrates stimulate microbial populations in plant root zones (rhizospheres) to cause removal of undesirable levels of contaminants in soil. This study characteri...Rhizodegradation is a process by which plant-supplied substrates stimulate microbial populations in plant root zones (rhizospheres) to cause removal of undesirable levels of contaminants in soil. This study characterized rhizodegradation of the insecticide bifenthrin in Armour silt loam and Sullivan fine sandy loam soils that were planted with switchgrass, big bluestem, and alfalfa. After six weeks in soils, plate dilution frequency assays (PDFA) of bacterial populations were higher in all planted soils than in unplanted ones. Planted Sullivan soils contained higher bacteria than corresponding Armour soils and alfalfa rhizospheres of both soil types contained highest bacteria. Bacterial populations generally increased between week 6 and week 10, before declining in each treatment at week 12. Carbon utilization patterns (CUP) of bacterial communities, measured as color development on BIOLOG plates, were higher in planted soils than in unplanted ones. Principal Component Analysis (PCA) constructed patterns based on different extents of color development;these patterns were used to relate microbial communities in the different treatments. Gas chromatography (GC-ECD) showed that significantly more bifenthrin dissipated in planted soils than unplanted ones. Different levels of bifenthrin were recovered in planted soils but the differences were generally not significant. Data are being evaluated further to provide a basis for the development of strategies for enhancing rhizodegradation of soils contaminated with bifenthrin.展开更多
[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A ...[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A total of 4 field trials were conducted in Guangdong Province,including 1%bifenthrin·thiamethoxam GR applied at the doses of 3,4 and 5 kg/667 m^(2),and 3%phoxim GR applied at the dose of 4 kg/667 m^(2).[Results]1%Bifenthrin·thiamethoxam GR applied at the dose of 5 kg/667 m^(2)had excellent control effects on sweet potato weevil,with an average control effect of 77.60%,which was significantly higher than that of 3%phoxim GR applied at the dose of 4 kg/667 m^(2)(48.52%).And the average yield increase rate of sweet potato treated with 1%bifenthrin·thiamethoxam GR reached 24.79%,significantly higher than 12.37%in the control group.[Conclusions]1%Bifenthrin·thiamethoxam GR should be evenly distributed on the ridge surface near sweet potato within 5-7 d after planting,and the recommended dosage is 5 kg/667 m^(2),which will have good control effect on sweet potato weevil and increase the yield of sweet potato.展开更多
Bifenthrin(BF) is an important type I synthetic fluorinated pyrethroid insecticide and acaricide.Previous investigations have indicated that the metabolisms of BF in human cells were through oxidative processes,and cy...Bifenthrin(BF) is an important type I synthetic fluorinated pyrethroid insecticide and acaricide.Previous investigations have indicated that the metabolisms of BF in human cells were through oxidative processes,and cytotoxicity was induced by the oxidative stress.In this study,the protective effects of EGCG,which is a major individual of green tea polyphenols,on the human embryonic lung fibroblast cell line HFL-I exposed to BF were investigated.The results showed that BF could induce oxidative stress leading to cytotoxicity in HFL-I cells.The pretreatment of EGCG at low concentrations significantly recovered the cell viability and morphology,inhibited excess generation of ROS,enhanced antioxidant enzyme activities and avoided loss of mitochondrial membrane potential.The results suggested that EGCG might eliminate the BF-induced damage in HFL-I cells.展开更多
基金Supported by Key Project of Science and Technology Plant of Haikou City(2009-043)Research Project of Hainan University (hd09xm78)~~
文摘[ Objective] The paper was to prepare bifenthrin nanoemulsions, and to characterize its property. [ Method ] Oil in water type of bifenthrin nanoemul- sions was prepared using emulsion phase transition method at constant temperature of 25℃. The formation mechanism of nanoemulsions was investigated, and the property of bffenthrin nanoemulsions was characterized by dynamic light scattering（DIS）, transmission electron microscopy （TEM）, contact angle meter, interfa- cial tension meter and high performance liquid chromatogTaphy （HPLC）. [ Result ] Phase transition occurred during the formation progress of bifenthrin nanoemul- sions ; the particles of nancomulsions system was spherical, and the particle size was mainly distributed in the range of 25 -30 ran; the contact angle on paraffin was less than 90° with good wetting effect; the surface tension was less than 40 mN/m, and the emulsification effect was also good, so the utilization rate of bifenthrin nancomulsions was improved. HPLC results showed that bffenthrin was not easy to decompose or precipitate with good stability. [ Conclusion] The result provided basis for the preparation of new types of insecticides.
基金supported by the National Natural Science Foundations of China (No. 20877071, 20837002)the National Basic Research Program (973) of China (No.2009CB421603)
文摘With the increasing use of synthetic pyrethroids （SPs）, the significance of ecological safety and health risk is an emerging concern, In this study, we evaluated the chronic aquatic toxicity of eis-bifenthrin （cis-BF） in Daphnia magna and its cytotoxicity in Chinese hamster ovary （CHO） cells as well as human cervical carcinoma （Hela） ceils. Chronic aquatic toxicity tests showed that cis-BF could significantly affect the reproduction of D. magna. The lowest observed effective concentration and the non-observed effective concentration of cis-BF to D. magna were 0.02 and 0.01 μg/L, respectively, and the chronic value was 0.014 μg/L. The intrinsic rate of natural increase was significantly decreased （p 〈 0.05） to 0.02 μg/L. The cytotoxicity assay demonstrated that cis-BF decreased cell viability in CHO and Hela cells in a concentration- and time-dependent manner. The IC50 values for Hela and CHO cells were 4.0 × 10^-5 and 3.2 × 10^-5 mol/L, respectively. Together, these results indicated that cis-BF induced chronic toxicity in both aquatic invertebrate animals and mammalian cells. These findings assist in understanding the impact of SPs on health and environmental safety. Considering the wide spectrum of SPs, a more comprehensive understanding of the negative effects is indispensible for planning future application and regulation of these pesticides.
文摘The acute and chronic toxic effects of bifenthrin on Daphnia magna were studied. The results showed that 24 h-EC 50 , 48 h-LC 50 and 96 h-LC 50 of bifenthrin on D. magna were 3.24, 12.40 and 1.40 μg/L respectively. And the LOEC and NOEC of bifenthrin were 0.02 and 0.004 μg/L respectively. The recovery test of bifenthrin on Daphnia magna was presented. Daphnia magna(F 0 generation) were exposed during 21 d to different bifenthrin concentrations. Offspring(animals from the first and third brood: F 1(1st) and F 1(3rd), respectively) were transferred to a free pesticide medium during a 21 d recovery period. In this recovery study, survival, growth, reproduction(mean total young per female, onset of reproduction and number broods per female) and the intrinsic rate of natural increase (r) were assessed as parameters. Reproduction such as number of young per female as well as length was still reduced in F 1(1st) generation daphnids from parentals(F 0) exposed to the bifenthrin. However F 1(3rd) individuals from parentals exposed to pesticide concentrations were able to restore reproduction when a recovery period of 21 d was allowed, but the length of F 1(3rd) from parentals exposed to the 0.5 and 0.75 μg/L bifenthrin concentration was still significantly effected(P<0.05).
基金The Natural Science Foundation of Fujian Province under contract No.2013N0029the Provincial Colleges and Universities in Fujian Province Department of Education Scientific Research Fund under contract No.JK2012061
文摘Bifenthrin（BF） is a pyrethroid insecticide that is widely used in agriculture, horticulture, and for residential purposes. However, few studies addressing the reproductive toxicity of BF on fishes are available. The present study was conducted to investigate the effects of BF on testicular development in Sebastiscus marmoratus and to gain insight into its mechanism. After exposure to 1, 10 and 100 ng/L BF for 50 days, there was a reduced number of mature sperm and an abundance of the late stages of spermatocysts in the testes. The levels of 17β-estradiol and testosterone were decreased significantly after BF exposure. The activity of caspase-3 was increased in a dosedependent manner after BF exposure, TUNEL assay indicated that BF exposure resulted in the occurrence of apoptosis in the testes, which might be main reason for the inhibition of spermatogenesis.
文摘Bifenthrin is an insecticide which is used to control insects, mites, and ticks. It poses a solemn en-vironmental threat and health risk to living organisms. It may be bioaccumulated or biomagnified at different trophic levels in the food chain by biota. Microbes are hidden creature of earth’s biodiversity. For isolation of bifenthrin degrading bacteria, rhizospheric soil samples of plants like Pisum sativum, Triticun aestvum, Chenopodium album were taken from tannery solid waste, Kasur, Pakistan. Enrichment culture techniques were used for the isolation of bacterial strains that showed luxurious growth on minimal growth media with bifenthrin dose was selected for biodegradation study. Bacteria were further screened out based on their morphological, biochemical parameters and degradation efficiency. Furthermore the effect of different growth factors like temperature, pH, inoculum concencentration, minimal inhibitory concentration of heavy metals and antibiotics were also studied. Bacterial strains of Xanthomonas and Bacillus sp. were identified as efficient degrading microbes. Maximum bifenthrin utilization were observed at 25°C (pH 7), with 500 μL inoculum of Bacillus sp., while Xanthomonas sp. gave optimm utilization at 30°C (pH 7) at the same inoculum volume of bacteria. The Rf values of Bacillus sp. and Xanthomonas sp. were 0.91 and 0.90 respectively, which indicated their potential to metabolize bifenthrin into nontoxic forms. These strains can be used to clean up the sites polluted with pesticides and tannery wastes when present in rhizosphere of plants.
文摘Rhizodegradation is a process by which plant-supplied substrates stimulate microbial populations in plant root zones (rhizospheres) to cause removal of undesirable levels of contaminants in soil. This study characterized rhizodegradation of the insecticide bifenthrin in Armour silt loam and Sullivan fine sandy loam soils that were planted with switchgrass, big bluestem, and alfalfa. After six weeks in soils, plate dilution frequency assays (PDFA) of bacterial populations were higher in all planted soils than in unplanted ones. Planted Sullivan soils contained higher bacteria than corresponding Armour soils and alfalfa rhizospheres of both soil types contained highest bacteria. Bacterial populations generally increased between week 6 and week 10, before declining in each treatment at week 12. Carbon utilization patterns (CUP) of bacterial communities, measured as color development on BIOLOG plates, were higher in planted soils than in unplanted ones. Principal Component Analysis (PCA) constructed patterns based on different extents of color development;these patterns were used to relate microbial communities in the different treatments. Gas chromatography (GC-ECD) showed that significantly more bifenthrin dissipated in planted soils than unplanted ones. Different levels of bifenthrin were recovered in planted soils but the differences were generally not significant. Data are being evaluated further to provide a basis for the development of strategies for enhancing rhizodegradation of soils contaminated with bifenthrin.
文摘[Objectives]The paper was to verify the field efficacy of 1%bifenthrin·thiamethoxam GR replacing organophosphorus GR against sweet potato weevil and its impact on the yield and quality of sweet potato.[Methods]A total of 4 field trials were conducted in Guangdong Province,including 1%bifenthrin·thiamethoxam GR applied at the doses of 3,4 and 5 kg/667 m^(2),and 3%phoxim GR applied at the dose of 4 kg/667 m^(2).[Results]1%Bifenthrin·thiamethoxam GR applied at the dose of 5 kg/667 m^(2)had excellent control effects on sweet potato weevil,with an average control effect of 77.60%,which was significantly higher than that of 3%phoxim GR applied at the dose of 4 kg/667 m^(2)(48.52%).And the average yield increase rate of sweet potato treated with 1%bifenthrin·thiamethoxam GR reached 24.79%,significantly higher than 12.37%in the control group.[Conclusions]1%Bifenthrin·thiamethoxam GR should be evenly distributed on the ridge surface near sweet potato within 5-7 d after planting,and the recommended dosage is 5 kg/667 m^(2),which will have good control effect on sweet potato weevil and increase the yield of sweet potato.
文摘Bifenthrin(BF) is an important type I synthetic fluorinated pyrethroid insecticide and acaricide.Previous investigations have indicated that the metabolisms of BF in human cells were through oxidative processes,and cytotoxicity was induced by the oxidative stress.In this study,the protective effects of EGCG,which is a major individual of green tea polyphenols,on the human embryonic lung fibroblast cell line HFL-I exposed to BF were investigated.The results showed that BF could induce oxidative stress leading to cytotoxicity in HFL-I cells.The pretreatment of EGCG at low concentrations significantly recovered the cell viability and morphology,inhibited excess generation of ROS,enhanced antioxidant enzyme activities and avoided loss of mitochondrial membrane potential.The results suggested that EGCG might eliminate the BF-induced damage in HFL-I cells.
