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John E Casida - One of the best experts on this subject based on the ideXlab platform.
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Cartap hydrolysis relative to its action at the insect nicotinic channel
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Pierluigi Caboni, Motohiro Tomizawa, John E CasidaAbstract:The insecticide Cartap is the bis(thiocarbamate) derivative of 2-(dimethylamino)propane-1,3-dithiol, which on oxidation forms the natural toxicant nereistoxin (NTX) [4-(dimethylamino)-1,2-dithiolane]. Both Cartap and NTX are ion channel blockers of the nicotinic acetylcholine receptor (nAChR). Cartap was originally proposed to act only after metabolic conversion to NTX and later suggested to block directly without activation. The present study uses a new approach to differentiate these hypotheses, that is, pH effects on channel-blocking activity and hydrolysis rates. As controls, mecamylamine (the classic channel blocker) and NTX are stable and similar in channel-blocking potency ([3H]thienylcyclohexylpiperidine binding assay, honeybee nAChR) at pH 6.1−8.4. In contrast, Cartap is >200-fold more effective at pH 7.4 than at pH 6.1, indicating that it undergoes hydrolytic activation. Cartap slowly hydrolyzes to Cartap monothiol at pH 6.1 but quickly forms the dithiol and some NTX at pH 7.4. The relationship ...
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Nereistoxin and Cartap Neurotoxicity Attributable to Direct Block of the Insect Nicotinic Receptor/Channel
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Motohiro Tomizawa, John E CasidaAbstract:Nereistoxin (NTX) (4-dimethylamino-1,2-dithiolane) is the naturally occurring prototype for Cartap [the bis(thiocarbamate) derivative of the NTX dithiol], which is generally regarded as a proinsecticide reverting to NTX. The aim of this study is to define the target site(s) for dithiolanes and dithiol esters. The affinity of [3H]NTX was not suitable for binding assays with honeybee (Apis mellifera) head membranes. However, NTX and Cartap are equally potent, direct-acting, and competitive displacers of [3H]thienylcyclohexylpiperidine binding at the noncompetitive blocker (NCB) site of the Apis nicotinic acetylcholine receptor (nAChR)/channel. NTX also binds at the Apis [3H]imidacloprid agonist site, but Cartap does not. As candidate metabolic pathways, sequential N-desmethylation and S-oxidation of NTX progressively reduce its potency at the NCB site and toxicity to houseflies. A P450 inhibitor reduces the toxicity of NTX and enhances it with Cartap. Surprisingly, Cartap is not just a pro-NTX but instead d...
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nereistoxin and Cartap neurotoxicity attributable to direct block of the insect nicotinic receptor channel
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Motohiro Tomizawa, John E CasidaAbstract:Nereistoxin (NTX) (4-dimethylamino-1,2-dithiolane) is the naturally occurring prototype for Cartap [the bis(thiocarbamate) derivative of the NTX dithiol], which is generally regarded as a proinsecticide reverting to NTX. The aim of this study is to define the target site(s) for dithiolanes and dithiol esters. The affinity of [3H]NTX was not suitable for binding assays with honeybee (Apis mellifera) head membranes. However, NTX and Cartap are equally potent, direct-acting, and competitive displacers of [3H]thienylcyclohexylpiperidine binding at the noncompetitive blocker (NCB) site of the Apis nicotinic acetylcholine receptor (nAChR)/channel. NTX also binds at the Apis [3H]imidacloprid agonist site, but Cartap does not. As candidate metabolic pathways, sequential N-desmethylation and S-oxidation of NTX progressively reduce its potency at the NCB site and toxicity to houseflies. A P450 inhibitor reduces the toxicity of NTX and enhances it with Cartap. Surprisingly, Cartap is not just a pro-NTX but instead d...
José Iannacone - One of the best experts on this subject based on the ideXlab platform.
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SELECTIVIDAD DEL INSECTICIDA Cartap EMPLEANDO BIOENSAYOS CON ORGANISMOS NO DESTINATARIOS SELECTIVITY OF THE Cartap INSECTICIDE EMPLOYING BIOASSAYS WITH NON TARGET ORGANISMS
2020Co-Authors: Ecología Aplicada, José Iannacone, Lorena AlvariñoAbstract:The aim of the current research was to evaluate Cartap (Bala® 50 SP) ecotoxicity on eight non target animal organisms: 1) Melanoides tuberculata (Muller, 1774) (Mollusca), 2) Emerita analoga (Stimpson, 1857) (Crustacea), 3) Chironomus calligraphus Goeldi, 1805 (Diptera), 4) Cyprinus carpio (Linne, 1758) (Osteichthyies), 5) Eisenia foetida (Savigny, 1826) (Annelida), 6) Podisus nigrispinus (Dallas, 1851) (Hemiptera), 7) Trichogramma fuentesi Torre, 1980 (Hymenoptera) and 8) Trichogrammatoidea bactrae Nagaraja. 1979 (Hymenoptera), and to evaluate selectivity of this insecticide. Acute toxicity parameters were mean lethal concentration (LC50) (mg o μg L), mean lethal dose (LD50) (mg o μg kg) and mean lethal time (TL50) (h). The sequence of sensibility to Cartap in the aquatic environment in terms of LC50 at 24 h exposure was: E. analoga > C. carpio > Ch. calligraphus > M. tuberculata. For E. foetida, with higher Cartap soil doses mortality was increased, and from 257 mg AI of Cartap kg onwards, diminishing wet weights were observed. In P. nigrispinus nymphs II, contact effects produced higher mortality than immersion effects. T. bactrae showed higher egg emergence sensibility than T. fuentesi. Cartap showed selectivity on seven of the eight species analyzed. Only E. analoga showed risks at the aquatic environmental level.
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EFECTOS ECOTOXICOLOGICOS DEL Cartap SOBRE POECILIA RETICULATA ''GUPPY'' (POECILIDAE) Y PARACHEIRODON INNESI ''NEON TETRA'' (CHARACIDAE) ECOTOXICOLOGICAL EFFECTS OF Cartap ON POECILIA RETICULATA ''GUPPY'' (POECILIDAE) AND PARACHEIRODON INNESI ''NEON T
2020Co-Authors: José Iannacone, Roxana Onofre, Olga HuanquiAbstract:The ecotoxicological impact of the carbamate insecticide Cartap (1,3 di (carbamoythio )-2-dimethyloaminopropan) used for agriculture pests and as mollusquicide of vectors of Public Health importance was evaluated, on two fish species of the continental aquatic ecosystem. Poecilia reticulata (Peters 1859) '' guppy" (Poecilidae) and Paracheirodon innesi (Myers 1936) '' Neon Tetra" (Characidae) were employed as non-target organisms in assays of short duration to determine the toxicological impact of Cartap. For both fish, percentage of mortality and two sublethal responses: increase of opercula movement and strange swim, were evaluated. In P. reticulata after 3 h exposure it was found a LC 50 (mean Lethal Concentration) of 6.75 mg'•L -1 and values of EC 50 (mean Effective Concentration) of
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selectividad del insecticida Cartap empleando bioensayos con organismos no destinatarios
Ecología Aplicada, 2016Co-Authors: José Iannacone, Lorena AlvariñoAbstract:El objetivo de la presente investigacion fue evaluar la ecotoxicidad del Cartap (Bala® 50 PS) sobre ocho organismos animales no destinatarios: 1) Melanoides tuberculata (Muller, 1774) (Mollusca), 2) Emerita analoga (Stimpson, 1857) (Crustacea), 3) Chironomus calligraphus Goeldi, 1805 (Diptera), 4) Cyprinus carpio (Linne, 1758) (Osteichyties), 5) Eisenia foetida (Savigny, 1826) (Annelida), 6) Podisus nigrispinus (Dallas, 1851) (Hemiptera), 7) Trichogramma fuentesi Torre, 1980 (Hymenoptera) y 8) Trichogrammatoidea bactrae Nagaraja, 1979 (Hymenoptera), y evaluar la selectividad de este insecticida. Los parametros de toxicidad aguda evaluados fueron la concentracion letal media (CL50) (mg o μg L-1), la dosis letal media (DL50) (mg o μg kg-1) y el tiempo letal medio (TL50) (h). La secuencia de sensibilidad al Cartap en el ambiente acuatico en terminos de CL50 a 24 h de exposicion fue: E. analoga > C. carpio > Ch. calligraphus > M. tuberculata. Para E. foetida, se encontro un incremento de la mortalidad con las dosis crecientes del Cartap en el suelo, y a partir de 257 mg IA de Cartap kg-1, se observo una disminucion del peso humedo. En las ninfas II de P. nigrispinus, el efecto de contacto produjo mayor mortalidad que el de inmersion. T. bactrae presento mayor sensibilidad en la emergencia de huevos que T. fuentesi. El Cartap mostro selectividad sobre siete de las ocho especies analizadas. Solo E. analoga presento un riesgo a nivel del ambiente acuatico.
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efectos ecotoxicologicos del Cartap sobre poecilia reticulata guppy poecilidae y paracheirodon innesi neon tetra characidae
Gayana, 2007Co-Authors: José Iannacone, Roxana Onofre, Olga HuanquiAbstract:Se evaluo el impacto ecotoxicologico del insecticida carbamico Cartap (1,3 di (carbamoytio)-2-dimetiloaminopropano) usado para el control de plagas agricolas y como molusquicida de vectores de importancia en Salud Publica, sobre dos especies de peces del ecosistema acuatico continental: Poecilia reticulata (Peters 1859) "guppy" (Poecilidae) y Paracheirodon innesi (Myers 1936) ``Neon Tetra" (Characidae). Ellos fueron utilizados como organismos no destinatarios en ensayos de corta duracion, para determinar el impacto toxicologico del Cartap. Para ambas especies de peces se evaluo el porcentaje de mortalidad, y dos respuestas subletales: el incremento del movimiento opercular y el nado extrano. A 3 h de exposicion para P. reticulata, se encontro un valor de CL50 (Concentracion letal media) de 6,75 mgL-1 y valores de CE50 (Concentracion efectiva media) de <7,55 y < 8,16 mgL-1 para el incremento del movimiento opercular y nado extrano, respectivamente. Para P. innesi, se encontro un valor de CL50 de <0,02 mgL-1 y valores de CE50 de < 0,01 y < 0,03 mgL-1, para el incremento del movimiento opercular y nado extrano, respectivamente. P. innesi fue mas sensible al Cartap que P. reticulata. Se calculo los cuocientes de riesgo (RQ) para la evaluacion del riesgo ambiental (ERA) de este insecticida sobre el ecosistema acuatico, indicando que P. innesi es mas adecuada que P. reticulata como herramienta ecotoxicologica para evaluar Cartap.
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efecto insecticida de cuatro extractos botanicos y del Cartap sobre la polilla de la papa phthorimaea operculella zeller lepidoptera gelechiidae en el peru
Entomotrópica: Revista internacional para el estudio de la entomología tropical, 2003Co-Authors: José Iannacone, Gerardo LamasAbstract:Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) es una plaga clave en el cultivo de papa en el Peru. Cuatro productos de origen botanico, la rotenona (Lonchocarpus nicou (Aublet) D C [Fabaceae]), la azadiractina (componente principal del nim, Azadirachta indica A. Juss [Meliaceae]), la lantana (Lantana camara L. [Verbenaceae]) y el molle (Schinus molle L. [Anacardiaceae]), asi como el plaguicida Cartap, fueron evaluados sobre huevecillos, larvas de primer estadio y adultos de P. operculella, en bioensayos de efectividad insecticida bajo condiciones de laboratorio. La eclosion de los huevos se vio afectada por la rotenona, el extracto hexanico al 10 % de lantana, el extracto acetonico al 10 % de molle, y el Cartap. La mortalidad de las larvas en los ensayos de ingestion fue afectada por la azadiractina desde 8 mg (IA) L-1, por la rotenona desde 400 mg (IA) L-1, por el Cartap a 1250 mg (IA) L-1 y por los tres extractos de lantana y de molle. La emergencia de pupas no fue afectada por ninguna de las sustancias quimicas empleadas. Ademas, ninguna de las sustancias quimicas empleadas causaron efectos estadisticamente significativos en el porcentaje de mortalidad de adultos de P. operculella, a excepcion del extracto acetonico al 10 % de molle y por Cartap. Se discute la posibilidad de empleo de estos insecticidas botanicos y el Cartap en un programa de Manejo Integrado de Plagas.
Yunfeng Chai - One of the best experts on this subject based on the ideXlab platform.
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dissipation pattern and safety evaluation of Cartap and its metabolites during tea planting tea manufacturing and brewing
Food Chemistry, 2020Co-Authors: Changling Jiang, Yunfeng Chai, Hongping ChenAbstract:Abstract There are few studies for risk assessment of Cartap and its metabolites, although Cartap is easily transformed into metabolites which could induce higher toxicity. This study aimed to investigate the dissipation pattern of Cartap and its metabolites during tea planting, manufacturing and brewing for evaluating the safety of Cartap pesticide. Cartap metabolites were identified using Q-Exactive Orbitrap mass spectrometry. Half-lives of Cartap in fresh tea leaves ranged from 0.49 to 0.59 days. Cartap decreased rapidly with time, and it was degraded into nereistoxin and Cartap monothiol during tea production chain. Cartap monothiol residues dissipated rapidly by 98% in three days during tea planting. Nereistoxin had a longer residual period than Cartap and it dominated the total residue in made tea after tea manufacturing. Transfer rates of nereistoxin during tea brewing ranged from 78.24% to 121.56%. Therefore, we suggested sum of Cartap and nereistoxin residues as maximum residual limits in tea.
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simultaneous determination of Cartap and its metabolite in tea using hydrophilic interaction chromatography tandem mass spectrometry and the combination of dispersive solid phase extraction and solid phase extraction
Journal of Chromatography A, 2019Co-Authors: Hongping Chen, Yunfeng ChaiAbstract:Abstract Risk assessment of Cartap residue in tea should include the exposure of Cartap and its metabolite due to rapid degradation of Cartap into nereistoxin. Herein, a reliable method for determination of Cartap and nereistoxin in tea was developed by hydrophilic interaction chromatography tandem mass spectrometry. Target compounds were extracted with water containing 1% formic acid and 5 mM ammonium formate. The use of dichloromethane effectively removed caffeine. Tea extracts were cleaned up by dispersive adsorbents of octadecylsilane and strong anion exchanger, then further purified using hydrophilic lipophilic balanced solid phase extraction cartridge. Isotopic internal standard was employed to calibrate the loss of analytes during sample preparation and compensate matrix effects. Method validation illustrated excellent linearity, with correlation coefficients (R2) higher than 0.999. Satisfactory recoveries of target compounds spiked in green tea, black tea and oolong tea ranged from 87.6% to 119.9% with intra- and inter-day precisions below 20%. Limits of quantification of Cartap and nereistoxin were 10.0 μg kg−1, and limits of detection were 2.0 μg kg−1 for Cartap and 4.0 μg kg−1 for nereistoxin. The developed method was applied to determine Cartap and nereistoxin in thirty tea samples.
Motohiro Tomizawa - One of the best experts on this subject based on the ideXlab platform.
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Cartap hydrolysis relative to its action at the insect nicotinic channel
Journal of Agricultural and Food Chemistry, 2004Co-Authors: Pierluigi Caboni, Motohiro Tomizawa, John E CasidaAbstract:The insecticide Cartap is the bis(thiocarbamate) derivative of 2-(dimethylamino)propane-1,3-dithiol, which on oxidation forms the natural toxicant nereistoxin (NTX) [4-(dimethylamino)-1,2-dithiolane]. Both Cartap and NTX are ion channel blockers of the nicotinic acetylcholine receptor (nAChR). Cartap was originally proposed to act only after metabolic conversion to NTX and later suggested to block directly without activation. The present study uses a new approach to differentiate these hypotheses, that is, pH effects on channel-blocking activity and hydrolysis rates. As controls, mecamylamine (the classic channel blocker) and NTX are stable and similar in channel-blocking potency ([3H]thienylcyclohexylpiperidine binding assay, honeybee nAChR) at pH 6.1−8.4. In contrast, Cartap is >200-fold more effective at pH 7.4 than at pH 6.1, indicating that it undergoes hydrolytic activation. Cartap slowly hydrolyzes to Cartap monothiol at pH 6.1 but quickly forms the dithiol and some NTX at pH 7.4. The relationship ...
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Nereistoxin and Cartap Neurotoxicity Attributable to Direct Block of the Insect Nicotinic Receptor/Channel
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Motohiro Tomizawa, John E CasidaAbstract:Nereistoxin (NTX) (4-dimethylamino-1,2-dithiolane) is the naturally occurring prototype for Cartap [the bis(thiocarbamate) derivative of the NTX dithiol], which is generally regarded as a proinsecticide reverting to NTX. The aim of this study is to define the target site(s) for dithiolanes and dithiol esters. The affinity of [3H]NTX was not suitable for binding assays with honeybee (Apis mellifera) head membranes. However, NTX and Cartap are equally potent, direct-acting, and competitive displacers of [3H]thienylcyclohexylpiperidine binding at the noncompetitive blocker (NCB) site of the Apis nicotinic acetylcholine receptor (nAChR)/channel. NTX also binds at the Apis [3H]imidacloprid agonist site, but Cartap does not. As candidate metabolic pathways, sequential N-desmethylation and S-oxidation of NTX progressively reduce its potency at the NCB site and toxicity to houseflies. A P450 inhibitor reduces the toxicity of NTX and enhances it with Cartap. Surprisingly, Cartap is not just a pro-NTX but instead d...
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nereistoxin and Cartap neurotoxicity attributable to direct block of the insect nicotinic receptor channel
Journal of Agricultural and Food Chemistry, 2003Co-Authors: Motohiro Tomizawa, John E CasidaAbstract:Nereistoxin (NTX) (4-dimethylamino-1,2-dithiolane) is the naturally occurring prototype for Cartap [the bis(thiocarbamate) derivative of the NTX dithiol], which is generally regarded as a proinsecticide reverting to NTX. The aim of this study is to define the target site(s) for dithiolanes and dithiol esters. The affinity of [3H]NTX was not suitable for binding assays with honeybee (Apis mellifera) head membranes. However, NTX and Cartap are equally potent, direct-acting, and competitive displacers of [3H]thienylcyclohexylpiperidine binding at the noncompetitive blocker (NCB) site of the Apis nicotinic acetylcholine receptor (nAChR)/channel. NTX also binds at the Apis [3H]imidacloprid agonist site, but Cartap does not. As candidate metabolic pathways, sequential N-desmethylation and S-oxidation of NTX progressively reduce its potency at the NCB site and toxicity to houseflies. A P450 inhibitor reduces the toxicity of NTX and enhances it with Cartap. Surprisingly, Cartap is not just a pro-NTX but instead d...
Olga Huanqui - One of the best experts on this subject based on the ideXlab platform.
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EFECTOS ECOTOXICOLOGICOS DEL Cartap SOBRE POECILIA RETICULATA ''GUPPY'' (POECILIDAE) Y PARACHEIRODON INNESI ''NEON TETRA'' (CHARACIDAE) ECOTOXICOLOGICAL EFFECTS OF Cartap ON POECILIA RETICULATA ''GUPPY'' (POECILIDAE) AND PARACHEIRODON INNESI ''NEON T
2020Co-Authors: José Iannacone, Roxana Onofre, Olga HuanquiAbstract:The ecotoxicological impact of the carbamate insecticide Cartap (1,3 di (carbamoythio )-2-dimethyloaminopropan) used for agriculture pests and as mollusquicide of vectors of Public Health importance was evaluated, on two fish species of the continental aquatic ecosystem. Poecilia reticulata (Peters 1859) '' guppy" (Poecilidae) and Paracheirodon innesi (Myers 1936) '' Neon Tetra" (Characidae) were employed as non-target organisms in assays of short duration to determine the toxicological impact of Cartap. For both fish, percentage of mortality and two sublethal responses: increase of opercula movement and strange swim, were evaluated. In P. reticulata after 3 h exposure it was found a LC 50 (mean Lethal Concentration) of 6.75 mg'•L -1 and values of EC 50 (mean Effective Concentration) of
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efectos ecotoxicologicos del Cartap sobre poecilia reticulata guppy poecilidae y paracheirodon innesi neon tetra characidae
Gayana, 2007Co-Authors: José Iannacone, Roxana Onofre, Olga HuanquiAbstract:Se evaluo el impacto ecotoxicologico del insecticida carbamico Cartap (1,3 di (carbamoytio)-2-dimetiloaminopropano) usado para el control de plagas agricolas y como molusquicida de vectores de importancia en Salud Publica, sobre dos especies de peces del ecosistema acuatico continental: Poecilia reticulata (Peters 1859) "guppy" (Poecilidae) y Paracheirodon innesi (Myers 1936) ``Neon Tetra" (Characidae). Ellos fueron utilizados como organismos no destinatarios en ensayos de corta duracion, para determinar el impacto toxicologico del Cartap. Para ambas especies de peces se evaluo el porcentaje de mortalidad, y dos respuestas subletales: el incremento del movimiento opercular y el nado extrano. A 3 h de exposicion para P. reticulata, se encontro un valor de CL50 (Concentracion letal media) de 6,75 mgL-1 y valores de CE50 (Concentracion efectiva media) de <7,55 y < 8,16 mgL-1 para el incremento del movimiento opercular y nado extrano, respectivamente. Para P. innesi, se encontro un valor de CL50 de <0,02 mgL-1 y valores de CE50 de < 0,01 y < 0,03 mgL-1, para el incremento del movimiento opercular y nado extrano, respectivamente. P. innesi fue mas sensible al Cartap que P. reticulata. Se calculo los cuocientes de riesgo (RQ) para la evaluacion del riesgo ambiental (ERA) de este insecticida sobre el ecosistema acuatico, indicando que P. innesi es mas adecuada que P. reticulata como herramienta ecotoxicologica para evaluar Cartap.