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Christopher A Reilly - One of the best experts on this subject based on the ideXlab platform.
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capsaicinoid metabolism by the generalist helicoverpa armigera and specialist h assulta species and tissue differences
Pesticide Biochemistry and Physiology, 2020Co-Authors: Jiang Zhu, Christopher A Reilly, Kai Tian, Xinghui QiuAbstract:Helicoverpa armigera and H. assulta are two of the few insects that can feed on hot pepper fruits. Capsaicin and Dihydrocapsaicin (i.e., capsaicinoids) are the principal pungent compounds in hot peppers. To explore possible molecular mechanisms of adaptation that allow these two species to consume capsaicinoids, the capacity of the three detoxification tissues (fat body, midgut, and Malpighian tubule) of the two pests, to metabolically degrade capsaicin and Dihydrocapsaicin, was compared. The results showed that capsaicin and Dihydrocapsaicin were metabolized by crude enzyme preparations from all three tissues of the two pests. Five metabolites of capsaicin, and five metabolites of Dihydrocapsaicin were identified. Tissue and species differences in the degree of capsaicin and Dihydrocapsaicin metabolism were observed. The specialist H. assulta had an overall greater capacity to degrade the capsaicinoids compared to the generalist H. armigera. Further, the midgut was the most significant contributor to capsaicinoid metabolism. The notably high specific activity in Malpighian tubules of H. armigera also further highlights the significance of this organ in xenobiotic detoxification. Alkyl hydroxylation and dehydrogenation were the main pathways for the oxidative biotransformation of both capsaicin and Dihydrocapsaicin by cytochrome P450s. This study provides evidence that enhanced metabolic decomposition of capsaicinoids may be an adaptation explaining dietary preferences for Capsicum fruits by these two pests.
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effects of vehicle on the uptake and elimination kinetics of capsaicinoids in human skin in vivo
Toxicology and Applied Pharmacology, 2004Co-Authors: Lynn K Pershing, Judy L Corlett, Christopher A Reilly, Dennis J CrouchAbstract:While the physiologic and molecular effects of capsaicinoids have been extensively studied in various model systems by a variety of administration routes, little is known about the uptake and elimination kinetic profiles in human skin following topical exposure. The present study evaluated the uptake and elimination kinetics of capsaicinoids in human stratum corneum following a single topical exposure to 3% solutions containing 55% capsaicin, 35% Dihydrocapsaicin, and 10% other analogues prepared in three vehicles: mineral oil (MO), propylene glycol (PG), and isopropyl alcohol (IPA). Capsaicinoid solutions were evaluated simultaneously in a random application pattern on the volar forearms of 12 subjects using a small, single 150-microg dose. Capsaicin and Dihydrocapsaicin were recovered from human skin using commercial adhesive discs to harvest stratum corneum from treated sites. Capsaicinoids were extracted from the stratum corneum-adhesive discs and quantified by liquid chromatography/mass spectroscopy (LC/MS). Both capsaicinoids were detected in stratum corneum 1 min after application with all vehicles and achieved a pseudo-steady state shortly thereafter. IPA delivered three times greater capsaicin and Dihydrocapsaicin into the human stratum corneum than PG or MO at all time points investigated. The Cmax of capsaicin in IPA, PG, and MO was 16.1, 6.2, and 6.5 microg, respectively. The Dihydrocapsaicin content was 60% of capsaicin with all vehicles. The estimated T(half) of capsaicin and Dihydrocapsaicin in the three vehicles was similar (24 h). Thus, maximal cutaneous capsaicinoid concentrations were achieved quickly in the human stratum corneum and were concentration and vehicle dependent. In contrast, capsaicinoid half-life was long and vehicle independent.
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determination of capsaicin nonivamide and Dihydrocapsaicin in blood and tissue by liquid chromatography tandem mass spectrometry
Journal of Analytical Toxicology, 2002Co-Authors: Christopher A Reilly, Dennis J Crouch, Garold S Yost, A. A. Abd-el FatahAbstract:A sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the analysis of capsaicin, nonivamide, and Dihydrocapsaicin in blood and tissue has been developed. The method utilized a one-step liquid-liquid extraction that yielded an approximate 90% recovery of capsaicinoids from blood. Chomatographic separation of the capsaicinoids was achieved using a reversed-phase high-performance liquid chromatography column and a stepwise gradient of methanol and distilled water containing 0.1% (v/v) formic acid. Identification and quantitation of the capsaicinoids was achieved using electrospray ionization-tandem mass spectrometry monitoring the precursor-to-product-ion transitions for the internal standard octanoyl vanillamide (m/z 280 --> 137), capsaicin (m/z 306 --> 137), Dihydrocapsaicin (m/z 308 -->137), and nonivamide (m/z 294 --> 137). Calibration curves, 1.0 to 250 ng/mL, were constructed by plotting concentration versus peak-area ratio (analyte/internal standard) and fitting the data with a weighted quadratic equation. The accuracy of the assay ranged from 90% to 107% for all analytes. The intra-assay precision (%RSD) for capsaicin was 4% at 2.5 ng/mL, 3% at 10 ng/mL, and 7% at 100 ng/mL. The interassay precision (% RSD) for capsaicin was 6% at 2.5 ng/mL, 6% at 10 ng/mL, and 7% at 100 ng/mL. Similar values for inter- and intra-assay precision were obtained for nonivamide and Dihydrocapsaicin. This method was used to assay for capsaicinoids in blood and tissue samples collected from rats exposed to capsaicinoids via nose-only inhalation. The concentration of capsaicin in these samples ranged from < 1.0 to 90.4 ng/mL in the blood, < 5.0 to 167 pg/mg in the lung, and < 2.0 to 3.4 pg/mg in the liver.
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Determination of capsaicin, Dihydrocapsaicin, and nonivamide in self-defense weapons by liquid chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry
Journal of Chromatography A, 2001Co-Authors: Christopher A Reilly, Dennis J Crouch, Garold S Yost, A. A. Abd-el FatahAbstract:Sensitive and selective liquid chromatography–mass spectrometry (LC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS–MS) methods for the analysis of capsaicin, Dihydrocapsaicin, and nonivamide in pepper spray products have been developed. Chromatographic separation of the capsaicinoid analogues was achieved using a reversed-phase HPLC column and a stepwise gradient of methanol and distilled water containing 0.1% (v/v) formic acid. Identification and quantification of the capsaicinoids was achieved by electrospray ionization single-stage mass spectrometry monitoring the protonated molecules of the internal standard (m/z 280), capsaicin (m/z 306), Dihydrocapsaicin (m/z 308), and nonivamide (m/z 294) or by tandem mass spectrometry monitoring the appropriate precursor-to-product-ion transitions. The plot of concentration versus peak area ratio was linear over the range of 10–750 ng/ml using LC–MS and 10–500 ng/ml using LC–MS–MS. However, to accurately quantify the capsaicinoids in the pepper spray products calibration curves between 10 and 1000 ng were constructed and fit using a weighted quadratic equation. Using the quadratic curve, the accuracy of the assay ranged from 91 to 102% for all analytes. The intra-assay precision (RSD) for capsaicin was 2% at 25 ng/ml, 10% at 500 ng/ml, and 3% at 800 ng/ml. The inter-assay precision (RSD) for capsaicin was 6% at 25 ng/ml, 6% at 500 ng/ml, and 9% at 800 ng/ml. Similar values for inter- and intra-assay precision were experimentally obtained for both Dihydrocapsaicin and nonivamide. The analysis of selected pepper spray products demonstrated that the capsaicinoid concentration in the products ranged from 0.7 to 40.5 μg/μl.
A. A. Abd-el Fatah - One of the best experts on this subject based on the ideXlab platform.
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determination of capsaicin nonivamide and Dihydrocapsaicin in blood and tissue by liquid chromatography tandem mass spectrometry
Journal of Analytical Toxicology, 2002Co-Authors: Christopher A Reilly, Dennis J Crouch, Garold S Yost, A. A. Abd-el FatahAbstract:A sensitive and selective liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the analysis of capsaicin, nonivamide, and Dihydrocapsaicin in blood and tissue has been developed. The method utilized a one-step liquid-liquid extraction that yielded an approximate 90% recovery of capsaicinoids from blood. Chomatographic separation of the capsaicinoids was achieved using a reversed-phase high-performance liquid chromatography column and a stepwise gradient of methanol and distilled water containing 0.1% (v/v) formic acid. Identification and quantitation of the capsaicinoids was achieved using electrospray ionization-tandem mass spectrometry monitoring the precursor-to-product-ion transitions for the internal standard octanoyl vanillamide (m/z 280 --> 137), capsaicin (m/z 306 --> 137), Dihydrocapsaicin (m/z 308 -->137), and nonivamide (m/z 294 --> 137). Calibration curves, 1.0 to 250 ng/mL, were constructed by plotting concentration versus peak-area ratio (analyte/internal standard) and fitting the data with a weighted quadratic equation. The accuracy of the assay ranged from 90% to 107% for all analytes. The intra-assay precision (%RSD) for capsaicin was 4% at 2.5 ng/mL, 3% at 10 ng/mL, and 7% at 100 ng/mL. The interassay precision (% RSD) for capsaicin was 6% at 2.5 ng/mL, 6% at 10 ng/mL, and 7% at 100 ng/mL. Similar values for inter- and intra-assay precision were obtained for nonivamide and Dihydrocapsaicin. This method was used to assay for capsaicinoids in blood and tissue samples collected from rats exposed to capsaicinoids via nose-only inhalation. The concentration of capsaicin in these samples ranged from < 1.0 to 90.4 ng/mL in the blood, < 5.0 to 167 pg/mg in the lung, and < 2.0 to 3.4 pg/mg in the liver.
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Determination of capsaicin, Dihydrocapsaicin, and nonivamide in self-defense weapons by liquid chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry
Journal of Chromatography A, 2001Co-Authors: Christopher A Reilly, Dennis J Crouch, Garold S Yost, A. A. Abd-el FatahAbstract:Sensitive and selective liquid chromatography–mass spectrometry (LC–MS) and liquid chromatography–tandem mass spectrometry (LC–MS–MS) methods for the analysis of capsaicin, Dihydrocapsaicin, and nonivamide in pepper spray products have been developed. Chromatographic separation of the capsaicinoid analogues was achieved using a reversed-phase HPLC column and a stepwise gradient of methanol and distilled water containing 0.1% (v/v) formic acid. Identification and quantification of the capsaicinoids was achieved by electrospray ionization single-stage mass spectrometry monitoring the protonated molecules of the internal standard (m/z 280), capsaicin (m/z 306), Dihydrocapsaicin (m/z 308), and nonivamide (m/z 294) or by tandem mass spectrometry monitoring the appropriate precursor-to-product-ion transitions. The plot of concentration versus peak area ratio was linear over the range of 10–750 ng/ml using LC–MS and 10–500 ng/ml using LC–MS–MS. However, to accurately quantify the capsaicinoids in the pepper spray products calibration curves between 10 and 1000 ng were constructed and fit using a weighted quadratic equation. Using the quadratic curve, the accuracy of the assay ranged from 91 to 102% for all analytes. The intra-assay precision (RSD) for capsaicin was 2% at 25 ng/ml, 10% at 500 ng/ml, and 3% at 800 ng/ml. The inter-assay precision (RSD) for capsaicin was 6% at 25 ng/ml, 6% at 500 ng/ml, and 9% at 800 ng/ml. Similar values for inter- and intra-assay precision were experimentally obtained for both Dihydrocapsaicin and nonivamide. The analysis of selected pepper spray products demonstrated that the capsaicinoid concentration in the products ranged from 0.7 to 40.5 μg/μl.
Ana Garcesclaver - One of the best experts on this subject based on the ideXlab platform.
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inheritance of capsaicin and Dihydrocapsaicin determined by hplc esi ms in an intraspecific cross of capsicum annuum l
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Ana Garcesclaver, Ramiro Gilortega, And Ana Alvarezfernandez, Maria Soledad ArnedoandresAbstract:The quantitative inheritance of capsaicin and Dihydrocapsaicin contents in fruits has been studied in an intraspecific cross of Capsicum annuum L. across two different environments, namely, fruits developed in spring and summer. A liquid chromatography-electrospray ionization/time-of-flight mass spectrometry [HPLC-ESI/MS(TOF)] method was used to identify and quantify capsaicin and Dihydrocapsaicin in extracts of pepper fruits. The analytical method used was able to determine the pungency of genotypes that, using other methods, would have been classified as non-pungent. Capsaicin and Dihydrocapsaicin contents varied largely among families, and families did not respond similarly in producing these capsaicinoids when their fruits were grown in spring and summer, with some families showing no increase, whereas in others, the increase was more than 2-fold. Heterosis for the pungency trait, assessed by the capsaicin and Dihydrocapsaicin contents in fruits, was found, indicating the existence of epistasis, over-dominance, or dominance complementation. Non-pungent parent alleles contributed to the capsaicin and Dihydrocapsaicin contents since transgressive segregation did occur. Furthermore, the type of gene action varied between capsaicin and Dihydrocapsaicin, and a seasonal effect during fruit development could affect gene action.
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determination of capsaicin and Dihydrocapsaicin in capsicum fruits by liquid chromatography electrospray time of flight mass spectrometry
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Ana Garcesclaver, Ramiro Gilortega, Maria Soledad Arnedoandres, Javier Abadia, Ana AlvarezfernandezAbstract:A simple, highly selective, sensitive, and reproducible liquid chromatography-electrospray ionization/time-of-flight mass spectrometry method has been developed for the direct and simultaneous determination of capsaicin and Dihydrocapsaicin in Capsicum fruit extracts. Capsaicin and Dihydrocapsaicin are the two major members of the so-called capsaicinoid family, which includes other minor analogues, and usually account for at least 90% of the pungency trait in Capsicum fruits. Chromatographic separation of capsaicin and Dihydrocapsaicin was achieved with a reversed-phase chromatography column, using a gradient of methanol and water. Quantification was done using as an internal standard (4,5-dimethoxybenzyl)-4-methyloctamide, a synthetic capsaicin analogue not found in nature. Analytes were base-peak resolved in less than 16 min, and limits of detection were 20 pmol for capsaicin and 4 pmol for Dihydrocapsaicin. The intraday repeatability values were lower than 0.5 and 12% for retention time and peak area, respectively, whereas the interday repeatability values were lower than 0.6 and 14% for retention time and peak area, respectively. Analyte recoveries found were 86 and 93% for capsaicin and Dihydrocapsaicin, respectively. The method developed has been applied to the identification and quantification of capsaicin and Dihydrocapsaicin in fruit extracts from different Capsicum genotypes, and concentrations found ranged from 2 to 6639 mg kg(-1).
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determination of capsaicin and Dihydrocapsaicin in capsicum fruits by liquid chromatography electrospray time of flight mass spectrometry
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Ana Garcesclaver, Ramiro Gilortega, Maria Soledad Arnedoandres, Javier Abadia, Ana AlvarezfernandezAbstract:A simple, highly selective, sensitive, and reproducible liquid chromatography−electrospray ionization/time-of-flight mass spectrometry method has been developed for the direct and simultaneous determination of capsaicin and Dihydrocapsaicin in Capsicum fruit extracts. Capsaicin and Dihydrocapsaicin are the two major members of the so-called capsaicinoid family, which includes other minor analogues, and usually account for at least 90% of the pungency trait in Capsicum fruits. Chromatographic separation of capsaicin and Dihydrocapsaicin was achieved with a reversed-phase chromatography column, using a gradient of methanol and water. Quantification was done using as an internal standard (4,5-dimethoxybenzyl)-4-methyloctamide, a synthetic capsaicin analogue not found in nature. Analytes were base-peak resolved in less than 16 min, and limits of detection were 20 pmol for capsaicin and 4 pmol for Dihydrocapsaicin. The intraday repeatability values were lower than 0.5 and 12% for retention time and peak area, ...
Ana Alvarezfernandez - One of the best experts on this subject based on the ideXlab platform.
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determination of capsaicin and Dihydrocapsaicin in capsicum fruits by liquid chromatography electrospray time of flight mass spectrometry
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Ana Garcesclaver, Ramiro Gilortega, Maria Soledad Arnedoandres, Javier Abadia, Ana AlvarezfernandezAbstract:A simple, highly selective, sensitive, and reproducible liquid chromatography-electrospray ionization/time-of-flight mass spectrometry method has been developed for the direct and simultaneous determination of capsaicin and Dihydrocapsaicin in Capsicum fruit extracts. Capsaicin and Dihydrocapsaicin are the two major members of the so-called capsaicinoid family, which includes other minor analogues, and usually account for at least 90% of the pungency trait in Capsicum fruits. Chromatographic separation of capsaicin and Dihydrocapsaicin was achieved with a reversed-phase chromatography column, using a gradient of methanol and water. Quantification was done using as an internal standard (4,5-dimethoxybenzyl)-4-methyloctamide, a synthetic capsaicin analogue not found in nature. Analytes were base-peak resolved in less than 16 min, and limits of detection were 20 pmol for capsaicin and 4 pmol for Dihydrocapsaicin. The intraday repeatability values were lower than 0.5 and 12% for retention time and peak area, respectively, whereas the interday repeatability values were lower than 0.6 and 14% for retention time and peak area, respectively. Analyte recoveries found were 86 and 93% for capsaicin and Dihydrocapsaicin, respectively. The method developed has been applied to the identification and quantification of capsaicin and Dihydrocapsaicin in fruit extracts from different Capsicum genotypes, and concentrations found ranged from 2 to 6639 mg kg(-1).
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determination of capsaicin and Dihydrocapsaicin in capsicum fruits by liquid chromatography electrospray time of flight mass spectrometry
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Ana Garcesclaver, Ramiro Gilortega, Maria Soledad Arnedoandres, Javier Abadia, Ana AlvarezfernandezAbstract:A simple, highly selective, sensitive, and reproducible liquid chromatography−electrospray ionization/time-of-flight mass spectrometry method has been developed for the direct and simultaneous determination of capsaicin and Dihydrocapsaicin in Capsicum fruit extracts. Capsaicin and Dihydrocapsaicin are the two major members of the so-called capsaicinoid family, which includes other minor analogues, and usually account for at least 90% of the pungency trait in Capsicum fruits. Chromatographic separation of capsaicin and Dihydrocapsaicin was achieved with a reversed-phase chromatography column, using a gradient of methanol and water. Quantification was done using as an internal standard (4,5-dimethoxybenzyl)-4-methyloctamide, a synthetic capsaicin analogue not found in nature. Analytes were base-peak resolved in less than 16 min, and limits of detection were 20 pmol for capsaicin and 4 pmol for Dihydrocapsaicin. The intraday repeatability values were lower than 0.5 and 12% for retention time and peak area, ...
Maria Soledad Arnedoandres - One of the best experts on this subject based on the ideXlab platform.
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inheritance of capsaicin and Dihydrocapsaicin determined by hplc esi ms in an intraspecific cross of capsicum annuum l
Journal of Agricultural and Food Chemistry, 2007Co-Authors: Ana Garcesclaver, Ramiro Gilortega, And Ana Alvarezfernandez, Maria Soledad ArnedoandresAbstract:The quantitative inheritance of capsaicin and Dihydrocapsaicin contents in fruits has been studied in an intraspecific cross of Capsicum annuum L. across two different environments, namely, fruits developed in spring and summer. A liquid chromatography-electrospray ionization/time-of-flight mass spectrometry [HPLC-ESI/MS(TOF)] method was used to identify and quantify capsaicin and Dihydrocapsaicin in extracts of pepper fruits. The analytical method used was able to determine the pungency of genotypes that, using other methods, would have been classified as non-pungent. Capsaicin and Dihydrocapsaicin contents varied largely among families, and families did not respond similarly in producing these capsaicinoids when their fruits were grown in spring and summer, with some families showing no increase, whereas in others, the increase was more than 2-fold. Heterosis for the pungency trait, assessed by the capsaicin and Dihydrocapsaicin contents in fruits, was found, indicating the existence of epistasis, over-dominance, or dominance complementation. Non-pungent parent alleles contributed to the capsaicin and Dihydrocapsaicin contents since transgressive segregation did occur. Furthermore, the type of gene action varied between capsaicin and Dihydrocapsaicin, and a seasonal effect during fruit development could affect gene action.
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determination of capsaicin and Dihydrocapsaicin in capsicum fruits by liquid chromatography electrospray time of flight mass spectrometry
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Ana Garcesclaver, Ramiro Gilortega, Maria Soledad Arnedoandres, Javier Abadia, Ana AlvarezfernandezAbstract:A simple, highly selective, sensitive, and reproducible liquid chromatography-electrospray ionization/time-of-flight mass spectrometry method has been developed for the direct and simultaneous determination of capsaicin and Dihydrocapsaicin in Capsicum fruit extracts. Capsaicin and Dihydrocapsaicin are the two major members of the so-called capsaicinoid family, which includes other minor analogues, and usually account for at least 90% of the pungency trait in Capsicum fruits. Chromatographic separation of capsaicin and Dihydrocapsaicin was achieved with a reversed-phase chromatography column, using a gradient of methanol and water. Quantification was done using as an internal standard (4,5-dimethoxybenzyl)-4-methyloctamide, a synthetic capsaicin analogue not found in nature. Analytes were base-peak resolved in less than 16 min, and limits of detection were 20 pmol for capsaicin and 4 pmol for Dihydrocapsaicin. The intraday repeatability values were lower than 0.5 and 12% for retention time and peak area, respectively, whereas the interday repeatability values were lower than 0.6 and 14% for retention time and peak area, respectively. Analyte recoveries found were 86 and 93% for capsaicin and Dihydrocapsaicin, respectively. The method developed has been applied to the identification and quantification of capsaicin and Dihydrocapsaicin in fruit extracts from different Capsicum genotypes, and concentrations found ranged from 2 to 6639 mg kg(-1).
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determination of capsaicin and Dihydrocapsaicin in capsicum fruits by liquid chromatography electrospray time of flight mass spectrometry
Journal of Agricultural and Food Chemistry, 2006Co-Authors: Ana Garcesclaver, Ramiro Gilortega, Maria Soledad Arnedoandres, Javier Abadia, Ana AlvarezfernandezAbstract:A simple, highly selective, sensitive, and reproducible liquid chromatography−electrospray ionization/time-of-flight mass spectrometry method has been developed for the direct and simultaneous determination of capsaicin and Dihydrocapsaicin in Capsicum fruit extracts. Capsaicin and Dihydrocapsaicin are the two major members of the so-called capsaicinoid family, which includes other minor analogues, and usually account for at least 90% of the pungency trait in Capsicum fruits. Chromatographic separation of capsaicin and Dihydrocapsaicin was achieved with a reversed-phase chromatography column, using a gradient of methanol and water. Quantification was done using as an internal standard (4,5-dimethoxybenzyl)-4-methyloctamide, a synthetic capsaicin analogue not found in nature. Analytes were base-peak resolved in less than 16 min, and limits of detection were 20 pmol for capsaicin and 4 pmol for Dihydrocapsaicin. The intraday repeatability values were lower than 0.5 and 12% for retention time and peak area, ...