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João B. Fernandes - One of the best experts on this subject based on the ideXlab platform.
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High-speed counter-current chromatographic isolation of Ricinine, an insecticide from Ricinus communis.
Journal of chromatography. A, 2009Co-Authors: Cristiane De Melo Cazal, Paulo C. Vieira, Jaqueline Raquel Batalhão, Vanessa De Cássia Domingues, Odair Corrêa Bueno, Edson Rodrigues Filho, Moacir Rossi Forim, Maria Fátima Das Graças Fernandes Da Silva, João B. FernandesAbstract:Abstract The alkaloid Ricinine, an insecticide for leaf-cutting ant ( Atta sexdens rubropilosa ), was obtained from Ricinus communis . A two-phase solvent system composed of CH 2 Cl 2 /EtOH/H 2 O (93:35:72, v/v/v) was used for high-speed counter-current chromatographic (HSCCC) isolation of Ricinine in high yield and with over 96% purity, as determined by liquid and gas chromatography–mass spectrometry (LC–MS and GC–MS). Identification of Ricinine was performed by comparison of 1 H NMR, 13 C NMR and LC–MS/MS data.
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Suscetibilidade de operárias e larvas de abelhas sociais em relação à ricinina Susceptibility of workers and larvae of social bees in relation to Ricinine
Fundação Zoobotânica do Rio Grande do Sul, 2009Co-Authors: Débora C. Rother, Tiago F. Souza, Osmar Malaspina, Odair C. Bueno, Maria De Fátima Das G. F. Da Silva, Paulo C. Vieira, João B. FernandesAbstract:Muitas substâncias de origem vegetal podem ser tóxicas ou apresentar potencial inseticida. Com o objetivo de diminuir a problemática da poluição ambiental alguns estudos vêm tentando substituir os inseticidas artificiais pelos inseticidas botânicos. Ricinus communis (Euphorbiaceae) apresenta uma grande variedade de substâncias sendo a ricinina o principal componente tóxico. Considerando que as abelhas são insetos benéficos por atuarem como agentes polinizadores das plantas, este estudo teve por objetivo avaliar o efeito tóxico da ricinina para as operárias e larvas de Apis mellifera (Linnaeus, 1758) (Hymenoptera, Apidae) e Scaptotrigona postica (Latreille, 1907) (Hymenoptera, Meliponini). Para isso, foram realizados testes de ingestão em operárias confinadas recebendo ricinina incorporada à dieta e testes de aplicação tópica com a substância solubilizada em metanol e aplicada no pronoto das abelhas com auxílio de uma microseringa. Para as larvas foram realizados testes de ingestão e calculada sua taxa de mortalidade. Os resultados mostram atividade tóxica significativa (p < 0.0001) da ricinina nas abelhas adultas das duas espécies para a concentração 0,1% nos testes de ingestão e 0,2% nos testes de aplicação tópica. Outrossim, uma elevada porcentagem de larvas foi afetada negativamente pela ricinina logo nos primeiros dias de vida para todas as concentrações testadas (0,25%, 0,5% e 1%).Many substances of vegetal origin can be toxic or present an insecticidal potential. With the aim of decreasing the environment pollution problem, a few studies are trying to substitute synthetic insecticides with botanical ones. Ricinus communis (Euphorbiaceae) presents a great variety of substances, being the Ricinine the main toxic component. Considering that bees are useful as pollinator agents of plants, this study evaluates toxicity potential of Ricinine on workers and larvae of Apis mellifera (Linnaeus, 1758) (Hymenoptera, Apidae) and Scaptotrigona postica (Latreille, 1907) (Hymenoptera, Meliponini). In order to determine Ricinine toxicity, ingestion tests were carried out with isolated workers bees that received Ricinine on its diet. Furthermore, for topic tests, solutions of Ricinine in methanol were applied on pronotum of worker bees with an "Agla" brand micrometer syringe outfit. For larvae of bees, ingestion tests were used and mortality rates were calculated. According to the results, it was detected a significant toxic activity (p < 0.0001) of Ricinine on the workers of the two bee species at concentrations of 0.1% in the ingestion tests and 0.2% in the topic tests. For all concentrations (0.25%, 0.5% and 1%), a high percentage of larvae bees was negatively affected by Ricinine on the first days of life
Rudolph C Johnson - One of the best experts on this subject based on the ideXlab platform.
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quantification of Ricinine and abrine in human plasma by hplc ms ms biomarkers of exposure to ricin and abrin
Journal of Analytical Toxicology, 2018Co-Authors: Samantha L Isenberg, Jerry D Thomas, Melissa D Carter, Michael A Miller, Aleksandra I Noras, Mike A Mojica, Sean T Carlsen, Chinthaka P Bulathsinghala, Rudolph C JohnsonAbstract:Ricin and abrin are toxic ribosome-inactivating proteins found in plants. Exposure to these toxins can be detected using the biomarkers Ricinine and abrine, which are present in the same plant sources as the toxins. The concentration of the biomarkers in urine and blood will be dependent upon the purification of abrin or ricin, the route of exposure, and the length of time between exposure and sample collection. Here, we present the first diagnostic assay for the simultaneous quantification of both Ricinine and abrine in blood matrices. Furthermore, this is the first-ever method for the detection of abrine in blood products. Samples were processed by isotope-dilution, solid-phase extraction, protein precipitation and quantification by HPLC-MS-MS. This analytical method detects abrine from 5.00 to 500 ng/mL and Ricinine from 0.300 to 300 ng/mL with coefficients of determination of 0.996 ± 0.003 and 0.998 ± 0.002 (n = 22), respectively. Quality control material accuracy was determined to have <10% relative error, and precision was within 19% relative standard deviation. The assay's time-to-first result is three hours including sample preparation. Furthermore, the method was applied for the quantification of Ricinine in the blood of a patient who had intentionally ingested castor beans to demonstrate the test was fit-for-purpose. This assay was designed to support the diagnosis of ricin and abrin exposures in public health investigations.
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Quantification of Ricinine and Abrine in Human Plasma by HPLC-MS-MS: Biomarkers of Exposure to Ricin and Abrin.
Journal of analytical toxicology, 2018Co-Authors: Samantha L Isenberg, Jerry D Thomas, Melissa D Carter, Michael A Miller, Aleksandra I Noras, Mike A Mojica, Sean T Carlsen, Chinthaka P Bulathsinghala, Rudolph C JohnsonAbstract:Ricin and abrin are toxic ribosome-inactivating proteins found in plants. Exposure to these toxins can be detected using the biomarkers Ricinine and abrine, which are present in the same plant sources as the toxins. The concentration of the biomarkers in urine and blood will be dependent upon the purification of abrin or ricin, the route of exposure, and the length of time between exposure and sample collection. Here, we present the first diagnostic assay for the simultaneous quantification of both Ricinine and abrine in blood matrices. Furthermore, this is the first-ever method for the detection of abrine in blood products. Samples were processed by isotope-dilution, solid-phase extraction, protein precipitation and quantification by HPLC-MS-MS. This analytical method detects abrine from 5.00 to 500 ng/mL and Ricinine from 0.300 to 300 ng/mL with coefficients of determination of 0.996 ± 0.003 and 0.998 ± 0.002 (n = 22), respectively. Quality control material accuracy was determined to have
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analysis of a ricin biomarker Ricinine in 989 individual human urine samples
Journal of Analytical Toxicology, 2013Co-Authors: Christopher T Pittman, Elizabeth I Hamelin, John M Guido, Thomas A Blake, Rudolph C JohnsonAbstract:Ricinine (3-cyano-4-methoxy-N-methyl-2-pyridone) is a urinary biomarker that can be measured to confirm human exposure to castor bean products such as ricin. Because many consumer products contain castor oil, another castor bean product, Ricinine may be detectable in the general population. The following study characterized urinary Ricinine concentrations from 989 individuals who were presumed to be unexposed to ricin. An automated diagnostic method was utilized to simplify the analysis of this large sample set. Sample preparation included a 96-well polystyrene divinylbenzene high throughput extraction and preconcentration step. Purified samples were analyzed by an efficient dual column, reversed-phase liquid chromatography separation and 13 C-isotope dilution tandem mass spectrometry. In this convenience sample set, only 1.2% of the urine specimens had detectable amounts of Ricinine, randomly distributed between 0.186 and 4.15 ng/mL.
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Stability of Ricinine, abrine, and alpha-amanitin in finished tap water
Analytical Methods, 2013Co-Authors: Jennifer S. Knaack, Christopher T Pittman, Joe V. Wooten, Justin T. Jacob, Matthew L. Magnuson, Erin E. Silvestri, Rudolph C JohnsonAbstract:Ricinine and abrine are potential indicators of drinking water contamination by ricin and abrin, respectively. Simultaneous detection of Ricinine and abrine, along with α-amanitin, another potential biotoxin water contaminant, is reportable through the use of automated sample preparation via solid phase extraction and detection using liquid chromatography/tandem-mass spectrometry. Performance of the method was characterized over eight analytical batches with quality control samples analyzed over 10 days. For solutions of analytes prepared with appropriate preservatives, the minimum reporting level (MRL) was 0.50 μg L−1 for Ricinine and abrine and 2.0 μg L−1 for α-amanitin. Among the analytes, the accuracy of the analysis ranged between 93 and 100% at concentrations of 1–2.5x the MRL, with analytical precision ranging from 4 to 8%. Five drinking waters representing a range of water quality parameters and disinfection practices were fortified with the analytes and analyzed over a 28 day period to determine their storage stability in these waters. The analytical signal from Ricinine was observed to be stable for 28 days after being spiked into all tap waters investigated. The analytical signal for abrine and α-amanitin decreased within 5 h after these analytes were spiked into some drinking waters, but afterwards, remained stable for 28 days. The magnitude of the decrease correlated with common water quality parameters potentially related to sorption of contaminants onto dissolved and colloidal components within the particular water. Even with the decrease, the detectability offered by the method may be 100–1000 times greater than potential toxicological benchmarks, suggesting the utility of the method for all three analytes, with additional quality control precautions for abrine and α-amanitin.
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evaluation of Ricinine a ricin biomarker from a non lethal castor bean ingestion
Journal of Analytical Toxicology, 2012Co-Authors: Elizabeth I Hamelin, Rudolph C Johnson, John D Osterloh, David J Howard, Jerry D ThomasAbstract:A case is presented of the attempted suicide of a 58-year-old man using castor beans. The patient came to the emergency room complaining of nausea, vomiting and diarrhea for nine hours following the ingestion of six castor beans. Urine samples were taken throughout the hospital stay and submitted to the Centers for Disease Control and Prevention for analysis of Ricinine, a castor bean component. The samples were found to be positive for Ricinine, with a maximum concentration of 674 µg/g-creatinine excreted approximately 23 h post-exposure. Subsequent samples demonstrated lower Ricinine concentrations, with the final sample taken at 62 h post-exposure at a concentration of 135 µg/g-creatinine of Ricinine. The estimated urinary excretion half-life was approximately 15 h and the recovery of Ricinine in the urine over the three days was estimated to be less than 10%. The patient fully recovered with supportive care and was discharged from the hospital six days after admission.
Micong Jin - One of the best experts on this subject based on the ideXlab platform.
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dispersive solid phase extraction followed by high performance liquid chromatography tandem mass spectrometry for the determination of Ricinine in cooking oil
Food Chemistry, 2014Co-Authors: Meiqiang Cai, Xiaohong Chen, Xiaoqing Wei, Sheng-dong Pan, Yong-gang Zhao, Micong JinAbstract:A rapid and accurate method by liquid chromatography/tandem mass spectrometry (LC-MS/MS) using positive electrospray was established for the determination of Ricinine in cooking oils. The homogenized samples, spiked with (13)C6-labelled Ricinine as an internal standard, were extracted using ethanol/water (20:80, v/v) and purified by dispersive solid-phase extraction (dSPE) using primary-secondary amine (PSA) and C18 as adsorbents. The extract was separated in a short C18 reversed-phase column using methanol/water (25:75, v/v) as the mobile phase and detected in multiple reaction monitoring (MRM) mode with the absolute matrix effect of 93.2-102.2%. The alkali-metal adduct ions were discussed and the mass/mass fragmentation pathway was explained. Ricinine showed good linearity in the range of 0.5-50.0 μg/kg with the limit of quantitation 0.5 μg/kg. The recoveries were between 86.0% and 98.3% with the intra- and inter-day RSDs of 2.6-7.0%, 5.5-10.8%, respectively. This method could be applied to the rapid quantification of Ricinine in cooking oils.
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Dispersive solid-phase extraction followed by high-performance liquid chromatography/tandem mass spectrometry for the determination of Ricinine in cooking oil
Food chemistry, 2014Co-Authors: Meiqiang Cai, Xiaohong Chen, Xiaoqing Wei, Sheng-dong Pan, Yong-gang Zhao, Micong JinAbstract:A rapid and accurate method by liquid chromatography/tandem mass spectrometry (LC-MS/MS) using positive electrospray was established for the determination of Ricinine in cooking oils. The homogenized samples, spiked with (13)C6-labelled Ricinine as an internal standard, were extracted using ethanol/water (20:80, v/v) and purified by dispersive solid-phase extraction (dSPE) using primary-secondary amine (PSA) and C18 as adsorbents. The extract was separated in a short C18 reversed-phase column using methanol/water (25:75, v/v) as the mobile phase and detected in multiple reaction monitoring (MRM) mode with the absolute matrix effect of 93.2-102.2%. The alkali-metal adduct ions were discussed and the mass/mass fragmentation pathway was explained. Ricinine showed good linearity in the range of 0.5-50.0 μg/kg with the limit of quantitation 0.5 μg/kg. The recoveries were between 86.0% and 98.3% with the intra- and inter-day RSDs of 2.6-7.0%, 5.5-10.8%, respectively. This method could be applied to the rapid quantification of Ricinine in cooking oils.
Claudio Da Cunha - One of the best experts on this subject based on the ideXlab platform.
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Amino acid and monoamine alterations in the cerebral cortex and hippocampus of mice submitted to Ricinine-induced seizures
Pharmacology biochemistry and behavior, 2002Co-Authors: Anete C. Ferraz, Esper A. Cavalheiro, Brás Heleno De Oliveira, Janete Aparecida Anselmo-franci, Sandra Regina Perosa, Eduardo Ferreira Castro-neto, M.i. Bellissimo, Maria Da Graça Naffah-mazzacoratti, Claudio Da CunhaAbstract:The alkaloid Ricinine isolated from the plant Ricinus communis, when administered to mice at high doses, induces clonic seizures accompanied by electroencephalographic alterations in the cerebral cortex and hippocampus. The lethal nature of Ricinine-induced seizures is considered to be a good model for the study of the events that cause death during clonic seizures, particularly those related to respiratory spasms. The initial signs (pre-seizure period) were marked by exophthalmus and decreased locomotor behavior. Animals killed during the preseizure period presented an increased utilization rate (HVA/DA) of dopamine (DA), an increased concentration of noradrenaline (NA), and a decreased concentration of glutamate (Glu), glutamine (Gln), taurine (Tau), and serotonin (5-HT) in the cerebral cortex. The seizure period is characterized by the occurrence of hind limb myoclonus and respiratory spasms, which are followed by death. Alterations in the cerebral cortex concentration of these neurotransmitters persisted during the seizure period. These alterations are only partially observed in the hippocampus, mainly during the seizure period. The present results suggest that an increased release of Glu in the cerebral cortex can be implicated in the genesis of the Ricinine-induced seizure and that it triggers many anticonvulsive mechanisms, like the release of Tau, DA, 5-HT, and NA.
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Ricinine-elicited seizures. A novel chemical model of convulsive seizures.
Pharmacology biochemistry and behavior, 2000Co-Authors: Anete C. Ferraz, Luiz Fernando Pereira, Rafaela L. Ribeiro, Claudia Wolfman, Jorge H. Medina, Fulvio A. Scorza, Neide Ferreira Dos Santos, Esper A. Cavalheiro, Claudio Da CunhaAbstract:The present investigation introduces Ricinine-elicited seizures as a novel chemical model of convulsive seizure. Ricinine, a neutral alkaloid obtained from the plant Ricinus communis, induces seizures when administered to mice at doses higher than 20 mg/kg. Animals presenting seizures showed a marked preconvulsive phase followed by short duration hind limb myoclonus, respiratory spasms, and death. The lethal nature of Ricinine seizures is also pointed out as a good model to study the events causing death in clonic seizures, particularly those related to respiratory spasms, which are also observed in some types of human epilepsy. The behavioral signs of Ricinine-elicited seizures are accompanied by electrographic alterations more evident during the preconvulsive phase in the cerebral cortex and more intense during the ictal phase both in the cortex and in the hippocampus. The Ricinine-elicited seizures may be inhibited by diazepam but not by phenobarbital, phenytoin, or ethosuximide. Micromolar concentrations of Ricinine cause a small decrease in the binding of [3H]-flunitrazepam to cerebral cortex membranes, but do not alter the binding of other radioligands to AMPA, 5-HT(1A), muscarinic, and alpha(1)-adrenergic receptors. Although Ricinine presents a cyanide radical, only higher doses of Ricinine (4 mM) caused a small impairment of mitochondrial respiration. These results suggest that the mechanism of action of Ricinine probably involves the benzodiazepine site in the GABA(A) receptor. This may represent a new mechanism of drug-elicited seizures that may contribute to a better understanding of epilepsy and to new therapeutic approaches to this disease.
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Pharmacological Evaluation of Ricinine, a Central Nervous System Stimulant Isolated from Ricinus communis
Pharmacology biochemistry and behavior, 1999Co-Authors: Anete C. Ferraz, Miriam Elizabeth Mendes Angelucci, Mariana L Da Costa, Ilza R Batista, Brás Heleno De Oliveira, Claudio Da CunhaAbstract:The extract of the pericarp of castor bean (Ricinus communis) showed some typical central nervous system stimulant effects when administered to mice. The animals became exophthalmic, presented tremors and clonic seizures and died a few minutes after receiving larger doses of the extract. At lower doses the extract improved memory consolidation and showed some neuroleptic-like properties, such as a decrease in exploratory behavior and catalepsy. The memory-improving effect and the seizure-eliciting properties of the extract were also observed with the administration of Ricinine, a neutral alkaloid isolated from the extract. However, the neuroleptic-like properties of the extract were not observed with Ricinine. As the therapeutic index of Ricinine is of the order of 200, the compound may be considered as a promising cognition-enhancing drug that may be used for the treatment of human amnesias.
Paulo C. Vieira - One of the best experts on this subject based on the ideXlab platform.
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High-speed counter-current chromatographic isolation of Ricinine, an insecticide from Ricinus communis.
Journal of chromatography. A, 2009Co-Authors: Cristiane De Melo Cazal, Paulo C. Vieira, Jaqueline Raquel Batalhão, Vanessa De Cássia Domingues, Odair Corrêa Bueno, Edson Rodrigues Filho, Moacir Rossi Forim, Maria Fátima Das Graças Fernandes Da Silva, João B. FernandesAbstract:Abstract The alkaloid Ricinine, an insecticide for leaf-cutting ant ( Atta sexdens rubropilosa ), was obtained from Ricinus communis . A two-phase solvent system composed of CH 2 Cl 2 /EtOH/H 2 O (93:35:72, v/v/v) was used for high-speed counter-current chromatographic (HSCCC) isolation of Ricinine in high yield and with over 96% purity, as determined by liquid and gas chromatography–mass spectrometry (LC–MS and GC–MS). Identification of Ricinine was performed by comparison of 1 H NMR, 13 C NMR and LC–MS/MS data.
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Suscetibilidade de operárias e larvas de abelhas sociais em relação à ricinina Susceptibility of workers and larvae of social bees in relation to Ricinine
Fundação Zoobotânica do Rio Grande do Sul, 2009Co-Authors: Débora C. Rother, Tiago F. Souza, Osmar Malaspina, Odair C. Bueno, Maria De Fátima Das G. F. Da Silva, Paulo C. Vieira, João B. FernandesAbstract:Muitas substâncias de origem vegetal podem ser tóxicas ou apresentar potencial inseticida. Com o objetivo de diminuir a problemática da poluição ambiental alguns estudos vêm tentando substituir os inseticidas artificiais pelos inseticidas botânicos. Ricinus communis (Euphorbiaceae) apresenta uma grande variedade de substâncias sendo a ricinina o principal componente tóxico. Considerando que as abelhas são insetos benéficos por atuarem como agentes polinizadores das plantas, este estudo teve por objetivo avaliar o efeito tóxico da ricinina para as operárias e larvas de Apis mellifera (Linnaeus, 1758) (Hymenoptera, Apidae) e Scaptotrigona postica (Latreille, 1907) (Hymenoptera, Meliponini). Para isso, foram realizados testes de ingestão em operárias confinadas recebendo ricinina incorporada à dieta e testes de aplicação tópica com a substância solubilizada em metanol e aplicada no pronoto das abelhas com auxílio de uma microseringa. Para as larvas foram realizados testes de ingestão e calculada sua taxa de mortalidade. Os resultados mostram atividade tóxica significativa (p < 0.0001) da ricinina nas abelhas adultas das duas espécies para a concentração 0,1% nos testes de ingestão e 0,2% nos testes de aplicação tópica. Outrossim, uma elevada porcentagem de larvas foi afetada negativamente pela ricinina logo nos primeiros dias de vida para todas as concentrações testadas (0,25%, 0,5% e 1%).Many substances of vegetal origin can be toxic or present an insecticidal potential. With the aim of decreasing the environment pollution problem, a few studies are trying to substitute synthetic insecticides with botanical ones. Ricinus communis (Euphorbiaceae) presents a great variety of substances, being the Ricinine the main toxic component. Considering that bees are useful as pollinator agents of plants, this study evaluates toxicity potential of Ricinine on workers and larvae of Apis mellifera (Linnaeus, 1758) (Hymenoptera, Apidae) and Scaptotrigona postica (Latreille, 1907) (Hymenoptera, Meliponini). In order to determine Ricinine toxicity, ingestion tests were carried out with isolated workers bees that received Ricinine on its diet. Furthermore, for topic tests, solutions of Ricinine in methanol were applied on pronotum of worker bees with an "Agla" brand micrometer syringe outfit. For larvae of bees, ingestion tests were used and mortality rates were calculated. According to the results, it was detected a significant toxic activity (p < 0.0001) of Ricinine on the workers of the two bee species at concentrations of 0.1% in the ingestion tests and 0.2% in the topic tests. For all concentrations (0.25%, 0.5% and 1%), a high percentage of larvae bees was negatively affected by Ricinine on the first days of life
