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Theresa M. Schreier - One of the best experts on this subject based on the ideXlab platform.
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depletion of Isoeugenol residues from the fillet tissue of aqui s exposed rainbow trout oncorhynchus mykiss
Aquaculture, 2009Co-Authors: Jeffery R. Meinertz, Theresa M. SchreierAbstract:Abstract There is a critical need in U.S. public aquaculture and fishery management for an approved sedative that allows for the immediate release of fish after sedation. AQUI-STM is a fish anesthetic/sedative approved for use in several countries and until recently was being developed in the U.S. as a sedative for immediate release of fish after sedation. The U.S. National Toxicology Program reported that Isoeugenol (the active ingredient in AQUI-STM) exposed male mice showed clear evidence of carcinogenicity, therefore efforts within the U.S. Department of Interior to develop AQUI-STM as a sedative that allows for immediate release ceased. Despite the ruling, AQUI-STM still has the potential to be approved as an anesthetic with a short withdrawal time. Among the data required to gain approval for use in the U.S. are data describing the composition and depletion of all AQUI-STM residues from fish fillet tissue. A total residue depletion study for AQUI-STM was conducted by exposing market-sized rainbow trout, Oncorhynchus mykiss (mean weight, 502.7 ± 54 g; s.d.) to 8.9 mg/L of 14C-[URL]-Isoeugenol for 60 min in 17 °C water. The 14C-[URL]-Isoeugenol was mixed with a surfactant resulting in a mixture that mimicked AQUI-STM. Groups of fish (n = 6) were sampled immediately after the exposure (0-h sample group) and at 0.5, 1, 2, and 4 h thereafter. Total Isoeugenol-equivalent residue concentrations in the fillet tissue were determined by oxidizing triplicate subsamples of homogenized skin-on fillet tissue from each fish to 14CO2 and enumerating the radioactivity by static liquid scintillation counting. Isoeugenol concentrations in fillet tissue were determined by extracting homogenized fillet tissue with solvents and determining the Isoeugenol concentrations in the extracts with high performance liquid chromatography techniques. The mean total Isoeugenol-equivalent residue concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 55.4, 32.0, 19.8, 11.3, and 4.9 µg/g, respectively. The primary chemical residue in fillet tissue from all exposed fish was Isoeugenol. The mean Isoeugenol concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 48.9, 26.5, 15.3, 7.2, and 2.2 µg/g, respectively. The percents of the total radioactivity classified as Isoeugenol in the 0, 0.5, 1, 2, and 4-h tissue extracts were 95, 73, 73, 64, and 48%, respectively.
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Depletion of Isoeugenol residues from the fillet tissue of AQUI-S™ exposed rainbow trout ( Oncorhynchus mykiss )
Aquaculture, 2009Co-Authors: Jeffery R. Meinertz, Theresa M. SchreierAbstract:Abstract There is a critical need in U.S. public aquaculture and fishery management for an approved sedative that allows for the immediate release of fish after sedation. AQUI-S TM is a fish anesthetic/sedative approved for use in several countries and until recently was being developed in the U.S. as a sedative for immediate release of fish after sedation. The U.S. National Toxicology Program reported that Isoeugenol (the active ingredient in AQUI-S TM ) exposed male mice showed clear evidence of carcinogenicity, therefore efforts within the U.S. Department of Interior to develop AQUI-S TM as a sedative that allows for immediate release ceased. Despite the ruling, AQUI-S TM still has the potential to be approved as an anesthetic with a short withdrawal time. Among the data required to gain approval for use in the U.S. are data describing the composition and depletion of all AQUI-S TM residues from fish fillet tissue. A total residue depletion study for AQUI-S TM was conducted by exposing market-sized rainbow trout, Oncorhynchus mykiss (mean weight, 502.7 ± 54 g; s.d.) to 8.9 mg/L of 14 C-[URL]-Isoeugenol for 60 min in 17 °C water. The 14 C-[URL]-Isoeugenol was mixed with a surfactant resulting in a mixture that mimicked AQUI-S TM . Groups of fish ( n = 6) were sampled immediately after the exposure (0-h sample group) and at 0.5, 1, 2, and 4 h thereafter. Total Isoeugenol-equivalent residue concentrations in the fillet tissue were determined by oxidizing triplicate subsamples of homogenized skin-on fillet tissue from each fish to 14 CO 2 and enumerating the radioactivity by static liquid scintillation counting. Isoeugenol concentrations in fillet tissue were determined by extracting homogenized fillet tissue with solvents and determining the Isoeugenol concentrations in the extracts with high performance liquid chromatography techniques. The mean total Isoeugenol-equivalent residue concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 55.4, 32.0, 19.8, 11.3, and 4.9 µg/g, respectively. The primary chemical residue in fillet tissue from all exposed fish was Isoeugenol. The mean Isoeugenol concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 48.9, 26.5, 15.3, 7.2, and 2.2 µg/g, respectively. The percents of the total radioactivity classified as Isoeugenol in the 0, 0.5, 1, 2, and 4-h tissue extracts were 95, 73, 73, 64, and 48%, respectively.
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Evaluation of a method for determining concentrations of Isoeugenol, an AQUI-S residue, in fillet tissue from freshwater fish species.
Journal of AOAC International, 2008Co-Authors: Jeffery R. Meinertz, Theresa M. Schreier, Jeffry A. BernardyAbstract:AQUI-S is a fish anesthetic/sedative that is approved for use in a number of countries throughout the world and has the potential for use in the United States. The active ingredient in AQUI-S is Isoeugenol. A method for determining Isoeugenol concentrations in edible fillet tissue is needed for regulatory purposes, including surveillance and potential use in studies fulfilling human food safety data requirements if U.S. Food and Drug Administration approval is pursued. A method was developed and evaluated for determining Isoeugenol concentrations in fillet tissue using relatively common procedures and equipment. The method produced accurate and precise results with fillet tissue from 10 freshwater fish species. The percentage of Isoeugenol recovered from samples fortified with Isoeugenol at nominal concentrations of 1, 50, and 100 microg/g for all species was always >80 and
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evaluation of a method for determining concentrations of Isoeugenol an aqui s residue in fillet tissue from freshwater fish species
Journal of AOAC International, 2008Co-Authors: Jeffery R. Meinertz, Theresa M. Schreier, Jeffry A. BernardyAbstract:AQUI-S is a fish anesthetic/sedative that is approved for use in a number of countries throughout the world and has the potential for use in the United States. The active ingredient in AQUI-S is Isoeugenol. A method for determining Isoeugenol concentrations in edible fillet tissue is needed for regulatory purposes, including surveillance and potential use in studies fulfilling human food safety data requirements if U.S. Food and Drug Administration approval is pursued. A method was developed and evaluated for determining Isoeugenol concentrations in fillet tissue using relatively common procedures and equipment. The method produced accurate and precise results with fillet tissue from 10 freshwater fish species. The percentage of Isoeugenol recovered from samples fortified with Isoeugenol at nominal concentrations of 1, 50, and 100 microg/g for all species was always >80 and <97%. Within-day precision for samples fortified at those same concentrations was < or =10%, and day-to-day precision was < or =4.0%. Method precision with fillet tissue containing biologically incurred Isoeugenol was < or =8.1%. There were no or minimal chromatographic interferences in control fillet tissue extracts from 9 of the 10 species. The method detection limits for all but one species ranged from 0.004 to 0.014 microg/g, and the quantitation limits ranged from 0.012 to 0.048 microg/g.
Jeffery R. Meinertz - One of the best experts on this subject based on the ideXlab platform.
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depletion of Isoeugenol residues from the fillet tissue of aqui s exposed rainbow trout oncorhynchus mykiss
Aquaculture, 2009Co-Authors: Jeffery R. Meinertz, Theresa M. SchreierAbstract:Abstract There is a critical need in U.S. public aquaculture and fishery management for an approved sedative that allows for the immediate release of fish after sedation. AQUI-STM is a fish anesthetic/sedative approved for use in several countries and until recently was being developed in the U.S. as a sedative for immediate release of fish after sedation. The U.S. National Toxicology Program reported that Isoeugenol (the active ingredient in AQUI-STM) exposed male mice showed clear evidence of carcinogenicity, therefore efforts within the U.S. Department of Interior to develop AQUI-STM as a sedative that allows for immediate release ceased. Despite the ruling, AQUI-STM still has the potential to be approved as an anesthetic with a short withdrawal time. Among the data required to gain approval for use in the U.S. are data describing the composition and depletion of all AQUI-STM residues from fish fillet tissue. A total residue depletion study for AQUI-STM was conducted by exposing market-sized rainbow trout, Oncorhynchus mykiss (mean weight, 502.7 ± 54 g; s.d.) to 8.9 mg/L of 14C-[URL]-Isoeugenol for 60 min in 17 °C water. The 14C-[URL]-Isoeugenol was mixed with a surfactant resulting in a mixture that mimicked AQUI-STM. Groups of fish (n = 6) were sampled immediately after the exposure (0-h sample group) and at 0.5, 1, 2, and 4 h thereafter. Total Isoeugenol-equivalent residue concentrations in the fillet tissue were determined by oxidizing triplicate subsamples of homogenized skin-on fillet tissue from each fish to 14CO2 and enumerating the radioactivity by static liquid scintillation counting. Isoeugenol concentrations in fillet tissue were determined by extracting homogenized fillet tissue with solvents and determining the Isoeugenol concentrations in the extracts with high performance liquid chromatography techniques. The mean total Isoeugenol-equivalent residue concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 55.4, 32.0, 19.8, 11.3, and 4.9 µg/g, respectively. The primary chemical residue in fillet tissue from all exposed fish was Isoeugenol. The mean Isoeugenol concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 48.9, 26.5, 15.3, 7.2, and 2.2 µg/g, respectively. The percents of the total radioactivity classified as Isoeugenol in the 0, 0.5, 1, 2, and 4-h tissue extracts were 95, 73, 73, 64, and 48%, respectively.
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Depletion of Isoeugenol residues from the fillet tissue of AQUI-S™ exposed rainbow trout ( Oncorhynchus mykiss )
Aquaculture, 2009Co-Authors: Jeffery R. Meinertz, Theresa M. SchreierAbstract:Abstract There is a critical need in U.S. public aquaculture and fishery management for an approved sedative that allows for the immediate release of fish after sedation. AQUI-S TM is a fish anesthetic/sedative approved for use in several countries and until recently was being developed in the U.S. as a sedative for immediate release of fish after sedation. The U.S. National Toxicology Program reported that Isoeugenol (the active ingredient in AQUI-S TM ) exposed male mice showed clear evidence of carcinogenicity, therefore efforts within the U.S. Department of Interior to develop AQUI-S TM as a sedative that allows for immediate release ceased. Despite the ruling, AQUI-S TM still has the potential to be approved as an anesthetic with a short withdrawal time. Among the data required to gain approval for use in the U.S. are data describing the composition and depletion of all AQUI-S TM residues from fish fillet tissue. A total residue depletion study for AQUI-S TM was conducted by exposing market-sized rainbow trout, Oncorhynchus mykiss (mean weight, 502.7 ± 54 g; s.d.) to 8.9 mg/L of 14 C-[URL]-Isoeugenol for 60 min in 17 °C water. The 14 C-[URL]-Isoeugenol was mixed with a surfactant resulting in a mixture that mimicked AQUI-S TM . Groups of fish ( n = 6) were sampled immediately after the exposure (0-h sample group) and at 0.5, 1, 2, and 4 h thereafter. Total Isoeugenol-equivalent residue concentrations in the fillet tissue were determined by oxidizing triplicate subsamples of homogenized skin-on fillet tissue from each fish to 14 CO 2 and enumerating the radioactivity by static liquid scintillation counting. Isoeugenol concentrations in fillet tissue were determined by extracting homogenized fillet tissue with solvents and determining the Isoeugenol concentrations in the extracts with high performance liquid chromatography techniques. The mean total Isoeugenol-equivalent residue concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 55.4, 32.0, 19.8, 11.3, and 4.9 µg/g, respectively. The primary chemical residue in fillet tissue from all exposed fish was Isoeugenol. The mean Isoeugenol concentrations in the 0, 0.5, 1, 2, and 4-h sample groups were 48.9, 26.5, 15.3, 7.2, and 2.2 µg/g, respectively. The percents of the total radioactivity classified as Isoeugenol in the 0, 0.5, 1, 2, and 4-h tissue extracts were 95, 73, 73, 64, and 48%, respectively.
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Evaluation of a method for determining concentrations of Isoeugenol, an AQUI-S residue, in fillet tissue from freshwater fish species.
Journal of AOAC International, 2008Co-Authors: Jeffery R. Meinertz, Theresa M. Schreier, Jeffry A. BernardyAbstract:AQUI-S is a fish anesthetic/sedative that is approved for use in a number of countries throughout the world and has the potential for use in the United States. The active ingredient in AQUI-S is Isoeugenol. A method for determining Isoeugenol concentrations in edible fillet tissue is needed for regulatory purposes, including surveillance and potential use in studies fulfilling human food safety data requirements if U.S. Food and Drug Administration approval is pursued. A method was developed and evaluated for determining Isoeugenol concentrations in fillet tissue using relatively common procedures and equipment. The method produced accurate and precise results with fillet tissue from 10 freshwater fish species. The percentage of Isoeugenol recovered from samples fortified with Isoeugenol at nominal concentrations of 1, 50, and 100 microg/g for all species was always >80 and
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evaluation of a method for determining concentrations of Isoeugenol an aqui s residue in fillet tissue from freshwater fish species
Journal of AOAC International, 2008Co-Authors: Jeffery R. Meinertz, Theresa M. Schreier, Jeffry A. BernardyAbstract:AQUI-S is a fish anesthetic/sedative that is approved for use in a number of countries throughout the world and has the potential for use in the United States. The active ingredient in AQUI-S is Isoeugenol. A method for determining Isoeugenol concentrations in edible fillet tissue is needed for regulatory purposes, including surveillance and potential use in studies fulfilling human food safety data requirements if U.S. Food and Drug Administration approval is pursued. A method was developed and evaluated for determining Isoeugenol concentrations in fillet tissue using relatively common procedures and equipment. The method produced accurate and precise results with fillet tissue from 10 freshwater fish species. The percentage of Isoeugenol recovered from samples fortified with Isoeugenol at nominal concentrations of 1, 50, and 100 microg/g for all species was always >80 and <97%. Within-day precision for samples fortified at those same concentrations was < or =10%, and day-to-day precision was < or =4.0%. Method precision with fillet tissue containing biologically incurred Isoeugenol was < or =8.1%. There were no or minimal chromatographic interferences in control fillet tissue extracts from 9 of the 10 species. The method detection limits for all but one species ranged from 0.004 to 0.014 microg/g, and the quantitation limits ranged from 0.012 to 0.048 microg/g.
Sung Su Yea - One of the best experts on this subject based on the ideXlab platform.
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Isoeugenol suppression of inducible nitric oxide synthase expression is mediated by down regulation of nf κb erk1 2 and p38 kinase
European Journal of Pharmacology, 2007Co-Authors: Chun-yeon Choi, Kyung-ran Park, Jung-hee Lee, Kwang-hyeon Liu, Dong-eun Kim, Young Jin Jeon, Sung Su YeaAbstract:Abstract Isoeugenol, which is a naturally occurring o-methoxyphenol in a variety of foods and essential oils, is known to have anti-inflammatory effects, although the mechanism is not clear. In the present study, we investigated the effect of Isoeugenol on NF-κB signaling leading to inducible nitric oxide synthase (iNOS) expression in RAW 264.7 murine macrophages stimulated with lipopolysaccharide (LPS). Isoeugenol markedly inhibited nitric oxide (NO) production in dose- and time-dependent manners. The decrease in NO production was found to correlate with a decrease in iNOS expression, as determined by Western blot analysis and real-time RT-PCR. To characterize further the inhibitory mechanisms of Isoeugenol at the transcriptional level, we examined the DNA-binding and transcriptional activities of NF-κB. Isoeugenol inhibited NF-κB-dependent transcriptional activity and DNA-binding activity by decreasing the nuclear translocation of p65, which is a component of NF-κB. In addition, Isoeugenol blocked signaling upstream of NF-κB activation, such as degradation of I-κBα and the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK), in LPS-stimulated RAW 264.7 cells. The Isoeugenol analogues eugenol and allylbenzene also inhibited LPS-induced NF-κB signaling and iNOS expression, albeit with less potency than Isoeugenol. These results suggest that Isoeugenol and its analogues inhibit NO production and iNOS expression in LPS-stimulated RAW 264.7 cells, and that these effects are mediated, at least in part, by blocking the phosphorylation of ERK1/2 and p38 kinase, degradation of I-κBα, and activation of NF-κB.
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Isoeugenol suppression of inducible nitric oxide synthase expression is mediated by down-regulation of NF-κB, ERK1/2, and p38 kinase
European Journal of Pharmacology, 2007Co-Authors: Chun-yeon Choi, Kyung-ran Park, Jung-hee Lee, Kwang-hyeon Liu, Dong-eun Kim, Young Jin Jeon, Sung Su YeaAbstract:Abstract Isoeugenol, which is a naturally occurring o-methoxyphenol in a variety of foods and essential oils, is known to have anti-inflammatory effects, although the mechanism is not clear. In the present study, we investigated the effect of Isoeugenol on NF-κB signaling leading to inducible nitric oxide synthase (iNOS) expression in RAW 264.7 murine macrophages stimulated with lipopolysaccharide (LPS). Isoeugenol markedly inhibited nitric oxide (NO) production in dose- and time-dependent manners. The decrease in NO production was found to correlate with a decrease in iNOS expression, as determined by Western blot analysis and real-time RT-PCR. To characterize further the inhibitory mechanisms of Isoeugenol at the transcriptional level, we examined the DNA-binding and transcriptional activities of NF-κB. Isoeugenol inhibited NF-κB-dependent transcriptional activity and DNA-binding activity by decreasing the nuclear translocation of p65, which is a component of NF-κB. In addition, Isoeugenol blocked signaling upstream of NF-κB activation, such as degradation of I-κBα and the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK), in LPS-stimulated RAW 264.7 cells. The Isoeugenol analogues eugenol and allylbenzene also inhibited LPS-induced NF-κB signaling and iNOS expression, albeit with less potency than Isoeugenol. These results suggest that Isoeugenol and its analogues inhibit NO production and iNOS expression in LPS-stimulated RAW 264.7 cells, and that these effects are mediated, at least in part, by blocking the phosphorylation of ERK1/2 and p38 kinase, degradation of I-κBα, and activation of NF-κB.
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Isoeugenol suppression of inducible nitric oxide synthase expression is mediated by down-regulation of NF-kappaB, ERK1/2, and p38 kinase.
European journal of pharmacology, 2007Co-Authors: Chun-yeon Choi, Kyung-ran Park, Jung-hee Lee, Kwang-hyeon Liu, Dong-eun Kim, Young Jin Jeon, Sung Su YeaAbstract:Isoeugenol, which is a naturally occurring o-methoxyphenol in a variety of foods and essential oils, is known to have anti-inflammatory effects, although the mechanism is not clear. In the present study, we investigated the effect of Isoeugenol on NF-kappaB signaling leading to inducible nitric oxide synthase (iNOS) expression in RAW 264.7 murine macrophages stimulated with lipopolysaccharide (LPS). Isoeugenol markedly inhibited nitric oxide (NO) production in dose- and time-dependent manners. The decrease in NO production was found to correlate with a decrease in iNOS expression, as determined by Western blot analysis and real-time RT-PCR. To characterize further the inhibitory mechanisms of Isoeugenol at the transcriptional level, we examined the DNA-binding and transcriptional activities of NF-kappaB. Isoeugenol inhibited NF-kappaB-dependent transcriptional activity and DNA-binding activity by decreasing the nuclear translocation of p65, which is a component of NF-kappaB. In addition, Isoeugenol blocked signaling upstream of NF-kappaB activation, such as degradation of I-kappaBalpha and the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK), in LPS-stimulated RAW 264.7 cells. The Isoeugenol analogues eugenol and allylbenzene also inhibited LPS-induced NF-kappaB signaling and iNOS expression, albeit with less potency than Isoeugenol. These results suggest that Isoeugenol and its analogues inhibit NO production and iNOS expression in LPS-stimulated RAW 264.7 cells, and that these effects are mediated, at least in part, by blocking the phosphorylation of ERK1/2 and p38 kinase, degradation of I-kappaBalpha, and activation of NF-kappaB.
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Suppression of interleukin-2 gene expression by Isoeugenol is mediated through down-regulation of NF-AT and NF-κB
International immunopharmacology, 2007Co-Authors: Kyung-ran Park, Jung-hee Lee, Chun-yeon Choi, Kwang-hyeon Liu, Dae-hyun Seog, Yong-ho Kim, Dong-eun Kim, Chul-ho Yun, Sung Su YeaAbstract:Isoeugenol is a naturally occurring methoxyphenol found in a variety of foods and essential oils. We investigated the effect of Isoeugenol on T-cell function and the regulatory mechanism underlying its effect. Isoeugenol and its structural analog eugenol suppressed the lymphoproliferative response to concanavalin A stimulation in B6C3F1 mouse splenocyte cultures. Isoeugenol inhibited phorbol 12-myristate 13-acetate (PMA) plus ionomycin (Io)-induced IL-2 mRNA expression and protein secretion in B6C3F1 mouse splenocytes, and in EL4.IL-2 mouse T-cells, as determined by real-time RT-PCR and ELISA, respectively. To further characterize the inhibitory mechanism of Isoeugenol at the transcriptional level, we examined the DNA binding activity of the transcription factors for IL-2 using an electrophoretic mobility shift assay. Isoeugenol decreased the binding activity of NF-AT and NF-κB in PMA/Io-stimulated EL4.IL-2 cells, but no significant effect was observed for AP-1 or Oct binding activity. Western blot analysis showed that Isoeugenol also decreased the nuclear translocation of cytoplasmic NF-AT and NF-κB. These results suggest that Isoeugenol suppresses IL-2 production through a decrease of IL-2 mRNA expression and that the inhibition is mediated, at least in part, through the down-regulation of NF-AT and NF-κB.
Jean-pierre Lepoittevin - One of the best experts on this subject based on the ideXlab platform.
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Deodorants: an experimental provocation study with Isoeugenol.
Contact dermatitis, 2005Co-Authors: Magnus Bruze, Jean-pierre Lepoittevin, Suresh Chandra Rastogi, Jeanne D Johansen, Ian R. White, Klaus Ejner Andersen, An Goossens, Peter J. Frosch, Torkil MennéAbstract:Axillary dermatitis is common and overrepresented in people with contact allergy to fragrances. Many people suspect their deodorants to be the incriminating products. In order to investigate the significance of Isoeugenol in deodorants for the development of axillary dermatitis when used by people with and without contact allergy to Isoeugenol, patch tests with deodorants and ethanol solutions with Isoeugenol, as well as repeated open application tests (ROAT) with roll-on deodorants with and without Isoeugenol at various concentrations, were performed in 35 dermatitis patients, 10 without and 25 with contact allergy to Isoeugenol. A positive ROAT was observed only in patients hypersensitive to Isoeugenol (P < 0.001) and only in the axilla to which the deodorants containing Isoeugenol had been applied (P < 0.001). Deodorants containing Isoeugenol in the concentration range of 0.0063–0.2% used 2 times daily on healthy skin can thus elicit axillary dermatitis within a few weeks in people with contact allergy to Isoeugenol.
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the time dose response relationship for elicitation of contact dermatitis in Isoeugenol allergic individuals
Toxicology and Applied Pharmacology, 2001Co-Authors: Klaus Ejner Andersen, Jean-pierre Lepoittevin, Suresh Chandra Rastogi, Jeanne D Johansen, Ian R. White, An Goossens, Peter J. Frosch, M Bruze, Torkil MennéAbstract:Abstract The elicitation response in allergic contact dermatitis is dose dependent, but the time-concentration relationship for elicitation has not previously been described. In this study 27 Isoeugenol-sensitive patients participated in serial dilution patch tests with Isoeugenol and a double-blinded Repeated Open Application Test (ROAT) using two concentrations of Isoeugenol, 0.2 and 0.05%. Seven controls without Isoeugenol allergy were also included. The participants applied 3.72±1.57 (mean ± SD) mg/cm2 of coded Isoeugenol solutions twice a day to a 3 × 3 cm2 area on the volar aspect of the right and left arm, respectively. For each test site the applications continued until a reaction appeared or for a maximum of 28 days. The minimal criteria for a positive reaction regarded as allergic contact dermatitis was persistent erythema at the ROAT test site. All controls were negative and 16 24 (66.7%) of the included Isoeugenol-sensitive subjects showed a positive ROAT to the 0.2% solution within the study period (Fisher's test,p=0.0024). Ten of the positive patients also reacted to the 0.05% solution. The median number of days until a positive reaction to the 0.2% solution was 7 days and was 15 days for the 0.05% solution. There was a highly significant correlation between the patients' patch test threshold and the number of days until a positive ROAT In conclusion, the time until an Isoeugenol allergic individual reacts in a ROAT depends on the individual sensitivity as well as the exposure concentrations; for low concentrations of the allergen or low degree of sensitivity, the allergic contact dermatitis may develop after several weeks of exposure. Therefore, a negative ROAT after 7 days may be a false negative.
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Isoeugenol is an important contact allergen: can it be safely replaced with isoeugenyl acetate?
Contact dermatitis, 1999Co-Authors: Ian R. White, Jean-pierre Lepoittevin, Suresh Chandra Rastogi, Jeanne D Johansen, Magnus Bruze, Elena Giménez Arnau, Klaus Ejner Andersen, P. J. Frosch, An Goossens, Torkil MennéAbstract:The prevalence of contact allergy to the fragrance mix in individuals with eczema is up to 10%. Within the mix, Isoeugenol (CAS 97-54-1) is an important individual allergen. Until May 1998, the IFRA (International Fragrance Assocation) guidelines suggested that Isoeugenol could safely be used at a level of 0.2% in consumer products. In May 1998, IFRA recommended that Isoeugenol should not be used at a level that exceeds 0.02% in consumer products, but did not provide guidance on allergen substitution. An alternative to Isoeugenol, based on aroma and absence of guidelines on use, is isoeugenyl acetate (CAS 93-29-8). 155 consecutive subjects were patch tested to isoeugenyl acetate (1.2%, 0.4%, 0.13% eth.) and Isoeugenol 1% pet. 6 (3.9%) had an allergic reaction to 1.2% isoeugenyl acetate at D4. The reactions to the other 2 dilutions tended to be graded. 8 individuals had at least a palpable erythema by D4 to Isoeugenol 1% pet. The majority of individuals allergic to Isoeugenol were also intolerant of isoeugenyl acetate. Effective labelling of fragrance substances on consumer products will facilitate monitoring of exposure.
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Skin sensitization to eugenol and Isoeugenol in mice: possible metabolic pathways involving ortho-quinone and quinone methide intermediates.
Chemical Research in Toxicology, 1997Co-Authors: Franck Bertrand, David A Basketter, David W. Roberts, Jean-pierre LepoittevinAbstract:With the aim of providing further mechanistic insights into the mode of action of eugenol (4-allyl-2-methoxyphenol) and Isoeugenol (4-propenyl-2-methoxyphenol), we have synthesized two series of modified compounds which were tested in the mouse local lymph node assay for their skin sensitizing potential. The replacement of the methoxy group by an isopropoxy group led to a complete loss of sensitization for the eugenol derivative 6a, while no significant effect was observed for the Isoeugenol derivative 6b. In the eugenol series, when methyl groups were present in the 3-, 5-, or 6-position a significant reduction in sensitization potential was observed while in the Isoeugenol series only methyl substitution in the 3- and 5-position had a discernable effect. Introduction of three methyl groups on the aromatic ring of eugenol (3,5,6-trimethyl-4-allyl-2-methoxyphenol, 7) and of a tert-butyl substituent at the γ-position of the alkyl chain of Isoeugenol (4-[3‘,3‘,3‘-trimethylpropenyl]-2-methoxyphenol, 8) led t...
Toru Nagasawa - One of the best experts on this subject based on the ideXlab platform.
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Purification, characterization and gene cloning of Isoeugenol-degrading enzyme from Pseudomonas putida IE27
Archives of Microbiology, 2007Co-Authors: Mamoru Yamada, Yukiyoshi Okada, Toyokazu Yoshida, Toru NagasawaAbstract:An Isoeugenol-degrading enzyme was purified to homogeneity from Pseudomonas putida IE27, an Isoeugenol-assimilating bacterium. The purified enzyme was a 55 kDa monomer and catalyzed the initial step of Isoeugenol degradation, the oxidative cleavage of the side chain double-bond of Isoeugenol, to form vanillin. Another reaction product of Isoeugenol degradation besides vanillin was identified to be acetaldehyde. The values of K m and k _cat for Isoeugenol were 175 μM and 5.18 s^–1, respectively. The purified enzyme catalyzed the incorporation of an oxygen atom from either molecular oxygen or water into vanillin, suggesting that the Isoeugenol-degrading enzyme is a kind of monooxygenase. The gene encoding the Isoeugenol-degrading enzyme and its flanking regions were isolated from P. putida IE27. The amino acid sequence of the enzyme was similar to those of lignostilbene-α,β-dioxygenases, carotenoid monooxygenases and 9- cis -epoxycarotenoid dioxygenases.
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Purification, characterization and gene cloning of Isoeugenol-degrading enzyme from Pseudomonas putida IE27.
Archives of microbiology, 2007Co-Authors: Mamoru Yamada, Yukiyoshi Okada, Toyokazu Yoshida, Toru NagasawaAbstract:An Isoeugenol-degrading enzyme was purified to homogeneity from Pseudomonas putida IE27, an Isoeugenol-assimilating bacterium. The purified enzyme was a 55 kDa monomer and catalyzed the initial step of Isoeugenol degradation, the oxidative cleavage of the side chain double-bond of Isoeugenol, to form vanillin. Another reaction product of Isoeugenol degradation besides vanillin was identified to be acetaldehyde. The values of Km and k (cat) for Isoeugenol were 175 muM and 5.18 s(-1), respectively. The purified enzyme catalyzed the incorporation of an oxygen atom from either molecular oxygen or water into vanillin, suggesting that the Isoeugenol-degrading enzyme is a kind of monooxygenase. The gene encoding the Isoeugenol-degrading enzyme and its flanking regions were isolated from P. putida IE27. The amino acid sequence of the enzyme was similar to those of lignostilbene-alpha,beta-dioxygenases, carotenoid monooxygenases and 9-cis-epoxycarotenoid dioxygenases.
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Biotransformation of Isoeugenol to vanillin by Pseudomonas putida IE27 cells
Applied Microbiology and Biotechnology, 2007Co-Authors: Mamoru Yamada, Yukiyoshi Okada, Toyokazu Yoshida, Toru NagasawaAbstract:The ability to produce vanillin and/or vanillic acid from Isoeugenol was screened using resting cells of various bacteria. The vanillin- and/or vanillic-acid-producing activities were observed in strains belonging to the genera Achromobacter , Aeromonas , Agrobacerium , Alcaligenes , Arthrobacter , Bacillus , Micrococcus , Pseudomonas , Rhodobacter , and Rhodococcus . Strain IE27, a soil isolate showing the highest vanillin-producing activity, was identified as Pseudomonas putida . We optimized the culture and reaction conditions for vanillin production from Isoeugenol using P. putida IE27 cells. The vanillin-producing activity was induced by adding Isoeugenol to the culture medium but not vanillin or eugenol. Under the optimized reaction conditions, P. putida IE27 cells produced 16.1 g/l vanillin from 150 mM Isoeugenol, with a molar conversion yield of 71% at 20 °C after a 24-h incubation in the presence of 10% ( v / v ) dimethyl sulfoxide.
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Conversion of Isoeugenol into vanillic acid byPseudomonas putida I58 cells exhibiting high Isoeugenol-degrading activity
Journal of bioscience and bioengineering, 2003Co-Authors: Hirotaka Furukawa, Toyokazu Yoshida, Hiroshi Morita, Toru NagasawaAbstract:Abstract Pseudomonas putida I58 was isolated from soil by a conventional enrichment culture method using Isoeugenol as a sole carbon source. The strain utilized Isoeugenol, vanillin and vanillic acid as carbon sources. On the other hand, the intermediates of the eugenol-degrading pathway, such as eugenol, coniferyl alcohol, coniferyl aldehyde and ferulic acid, were not utilized by this strain, indicating that Isoeugenol is directly degraded to vanillin without the formation of ferulic acid. The resting cells ofP. putida I58 rapidly converted Isoeugenol into vanillic acid via vanillin with a conversion yield of 98% by 40-min incubation.
