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Hannu Perakyla - One of the best experts on this subject based on the ideXlab platform.
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structure activity relationships of bacterial mutagens related to 3 chloro 4 dichloromethyl 5 hydroxy 2 5h furanone an emphasis on the effect of stepwise removal of chlorine from the dichloromethyl group
Chemical Research in Toxicology, 1991Co-Authors: Robert T Lalonde, Gary P Cook, Hannu PerakylaAbstract:The Salmonella typhimurium (TA100) mutagenicities of six structural analogues of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) were determined and compared. These were also compared to previously determined mutagenicities for another four analogues. This study was conducted for the primary purpose of ascertaining the effect of C-6 chlorine-by-hydrogen replacement on Mutagenicity. The compounds assayed were 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 3-chloro-4-methyl-5-hydroxy-2(5H)-furanone (7), 3-chloro-4-methyl-2(5H)-furanone (8), 4-methyl-5-hydroxy-2(5H)-furanone (9), and 4-methyl-2(5H)-furanone (10). Compounds 3, 4, and 7 were mutagenic whereas 8-10 were not. All six compounds were stable under assay conditions. Mutagenicity data for the three active compounds were combined with data of another four active compounds studied previously to obtain an expanded data set. Mutagenicities of the seven compounds were compared, pairwise, in 21 comparisons and then by multiple regression analysis. On the average, chlorine-by-hydrogen replacement of a single chlorine located at a chloromethyl group (C-6) had a markedly greater effect in reducing Mutagenicity than a similar replacement at C-3 or a hydroxyl-by-hydrogen replacement at C-5. The chlorine-by-hydrogen replacement at C-6 of compound 3 resulted in the greatest Mutagenicity reduction of any single replacement and amounted to a 10(3)-fold diminished Mutagenicity.
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effect on Mutagenicity of the stepwise removal of hydroxyl group and chlorine atoms from 3 chloro 4 dichloromethyl 5 hydroxy 2 5h furanone carbon 13 nmr chemical shifts as determinants of Mutagenicity
Chemical Research in Toxicology, 1991Co-Authors: Robert T Lalonde, Gary P Cook, Hannu Perakyla, Carlton W DenceAbstract:The response of Mutagenicity to the stepwise replacement of chlorine atoms and the hydroxyl group by hydrogen in 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX, 1) was determined in several assays by using Salmonella typhimurium tester strain (TA100). In all, eight MX derivatives were assayed. Several were studied together in at least one assay. In addition to MX, the seven included 3-chloro-4-(dichloromethyl)-2(5H)-furanone (RMX, 2), 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 4-(chloromethyl)-5-hydroxy-2(5H)-furanone (5), 4-chloromethyl-2(5H)-furanone (6), and 4-(dichloromethyl)-2(5H)-furanone (8). Compounds 1-6 were mutagenic. Compound 8 gave erratic results. 4-(Acetoxymethyl)-2(5H)-furanone (11) was nonmutagenic. The largest drop in Mutagenicity amounted to a factor of about 10(2) for the replacement of the hydroxyl group or a C-3 chlorine atom from 3. Other replacements of the hydroxyl group or a C-3 or C-6 chlorine atom amounted to Mutagenicity diminished by a factor of only 10. On the basis of the rates of UV spectral changes under assay conditions, chemical half-life values (ct 1/2) for 1-6 and 8 were estimated as indicators of compound stability. However, Mutagenicity differences were shown to result principally from the intrinsic mutagenicities of the six compounds 1-6 rather than from differences in stability.(ABSTRACT TRUNCATED AT 250 WORDS)
Robert T Lalonde - One of the best experts on this subject based on the ideXlab platform.
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structure activity relationships of bacterial mutagens related to 3 chloro 4 dichloromethyl 5 hydroxy 2 5h furanone an emphasis on the effect of stepwise removal of chlorine from the dichloromethyl group
Chemical Research in Toxicology, 1991Co-Authors: Robert T Lalonde, Gary P Cook, Hannu PerakylaAbstract:The Salmonella typhimurium (TA100) mutagenicities of six structural analogues of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) were determined and compared. These were also compared to previously determined mutagenicities for another four analogues. This study was conducted for the primary purpose of ascertaining the effect of C-6 chlorine-by-hydrogen replacement on Mutagenicity. The compounds assayed were 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 3-chloro-4-methyl-5-hydroxy-2(5H)-furanone (7), 3-chloro-4-methyl-2(5H)-furanone (8), 4-methyl-5-hydroxy-2(5H)-furanone (9), and 4-methyl-2(5H)-furanone (10). Compounds 3, 4, and 7 were mutagenic whereas 8-10 were not. All six compounds were stable under assay conditions. Mutagenicity data for the three active compounds were combined with data of another four active compounds studied previously to obtain an expanded data set. Mutagenicities of the seven compounds were compared, pairwise, in 21 comparisons and then by multiple regression analysis. On the average, chlorine-by-hydrogen replacement of a single chlorine located at a chloromethyl group (C-6) had a markedly greater effect in reducing Mutagenicity than a similar replacement at C-3 or a hydroxyl-by-hydrogen replacement at C-5. The chlorine-by-hydrogen replacement at C-6 of compound 3 resulted in the greatest Mutagenicity reduction of any single replacement and amounted to a 10(3)-fold diminished Mutagenicity.
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effect on Mutagenicity of the stepwise removal of hydroxyl group and chlorine atoms from 3 chloro 4 dichloromethyl 5 hydroxy 2 5h furanone carbon 13 nmr chemical shifts as determinants of Mutagenicity
Chemical Research in Toxicology, 1991Co-Authors: Robert T Lalonde, Gary P Cook, Hannu Perakyla, Carlton W DenceAbstract:The response of Mutagenicity to the stepwise replacement of chlorine atoms and the hydroxyl group by hydrogen in 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX, 1) was determined in several assays by using Salmonella typhimurium tester strain (TA100). In all, eight MX derivatives were assayed. Several were studied together in at least one assay. In addition to MX, the seven included 3-chloro-4-(dichloromethyl)-2(5H)-furanone (RMX, 2), 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 4-(chloromethyl)-5-hydroxy-2(5H)-furanone (5), 4-chloromethyl-2(5H)-furanone (6), and 4-(dichloromethyl)-2(5H)-furanone (8). Compounds 1-6 were mutagenic. Compound 8 gave erratic results. 4-(Acetoxymethyl)-2(5H)-furanone (11) was nonmutagenic. The largest drop in Mutagenicity amounted to a factor of about 10(2) for the replacement of the hydroxyl group or a C-3 chlorine atom from 3. Other replacements of the hydroxyl group or a C-3 or C-6 chlorine atom amounted to Mutagenicity diminished by a factor of only 10. On the basis of the rates of UV spectral changes under assay conditions, chemical half-life values (ct 1/2) for 1-6 and 8 were estimated as indicators of compound stability. However, Mutagenicity differences were shown to result principally from the intrinsic mutagenicities of the six compounds 1-6 rather than from differences in stability.(ABSTRACT TRUNCATED AT 250 WORDS)
Gary P Cook - One of the best experts on this subject based on the ideXlab platform.
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structure activity relationships of bacterial mutagens related to 3 chloro 4 dichloromethyl 5 hydroxy 2 5h furanone an emphasis on the effect of stepwise removal of chlorine from the dichloromethyl group
Chemical Research in Toxicology, 1991Co-Authors: Robert T Lalonde, Gary P Cook, Hannu PerakylaAbstract:The Salmonella typhimurium (TA100) mutagenicities of six structural analogues of 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) were determined and compared. These were also compared to previously determined mutagenicities for another four analogues. This study was conducted for the primary purpose of ascertaining the effect of C-6 chlorine-by-hydrogen replacement on Mutagenicity. The compounds assayed were 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 3-chloro-4-methyl-5-hydroxy-2(5H)-furanone (7), 3-chloro-4-methyl-2(5H)-furanone (8), 4-methyl-5-hydroxy-2(5H)-furanone (9), and 4-methyl-2(5H)-furanone (10). Compounds 3, 4, and 7 were mutagenic whereas 8-10 were not. All six compounds were stable under assay conditions. Mutagenicity data for the three active compounds were combined with data of another four active compounds studied previously to obtain an expanded data set. Mutagenicities of the seven compounds were compared, pairwise, in 21 comparisons and then by multiple regression analysis. On the average, chlorine-by-hydrogen replacement of a single chlorine located at a chloromethyl group (C-6) had a markedly greater effect in reducing Mutagenicity than a similar replacement at C-3 or a hydroxyl-by-hydrogen replacement at C-5. The chlorine-by-hydrogen replacement at C-6 of compound 3 resulted in the greatest Mutagenicity reduction of any single replacement and amounted to a 10(3)-fold diminished Mutagenicity.
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effect on Mutagenicity of the stepwise removal of hydroxyl group and chlorine atoms from 3 chloro 4 dichloromethyl 5 hydroxy 2 5h furanone carbon 13 nmr chemical shifts as determinants of Mutagenicity
Chemical Research in Toxicology, 1991Co-Authors: Robert T Lalonde, Gary P Cook, Hannu Perakyla, Carlton W DenceAbstract:The response of Mutagenicity to the stepwise replacement of chlorine atoms and the hydroxyl group by hydrogen in 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX, 1) was determined in several assays by using Salmonella typhimurium tester strain (TA100). In all, eight MX derivatives were assayed. Several were studied together in at least one assay. In addition to MX, the seven included 3-chloro-4-(dichloromethyl)-2(5H)-furanone (RMX, 2), 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 4-(chloromethyl)-5-hydroxy-2(5H)-furanone (5), 4-chloromethyl-2(5H)-furanone (6), and 4-(dichloromethyl)-2(5H)-furanone (8). Compounds 1-6 were mutagenic. Compound 8 gave erratic results. 4-(Acetoxymethyl)-2(5H)-furanone (11) was nonmutagenic. The largest drop in Mutagenicity amounted to a factor of about 10(2) for the replacement of the hydroxyl group or a C-3 chlorine atom from 3. Other replacements of the hydroxyl group or a C-3 or C-6 chlorine atom amounted to Mutagenicity diminished by a factor of only 10. On the basis of the rates of UV spectral changes under assay conditions, chemical half-life values (ct 1/2) for 1-6 and 8 were estimated as indicators of compound stability. However, Mutagenicity differences were shown to result principally from the intrinsic mutagenicities of the six compounds 1-6 rather than from differences in stability.(ABSTRACT TRUNCATED AT 250 WORDS)
Carlton W Dence - One of the best experts on this subject based on the ideXlab platform.
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effect on Mutagenicity of the stepwise removal of hydroxyl group and chlorine atoms from 3 chloro 4 dichloromethyl 5 hydroxy 2 5h furanone carbon 13 nmr chemical shifts as determinants of Mutagenicity
Chemical Research in Toxicology, 1991Co-Authors: Robert T Lalonde, Gary P Cook, Hannu Perakyla, Carlton W DenceAbstract:The response of Mutagenicity to the stepwise replacement of chlorine atoms and the hydroxyl group by hydrogen in 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX, 1) was determined in several assays by using Salmonella typhimurium tester strain (TA100). In all, eight MX derivatives were assayed. Several were studied together in at least one assay. In addition to MX, the seven included 3-chloro-4-(dichloromethyl)-2(5H)-furanone (RMX, 2), 3-chloro-4-(chloromethyl)-5-hydroxy-2(5H)-furanone (3), 3-chloro-4-(chloromethyl)-2(5H)-furanone (4), 4-(chloromethyl)-5-hydroxy-2(5H)-furanone (5), 4-chloromethyl-2(5H)-furanone (6), and 4-(dichloromethyl)-2(5H)-furanone (8). Compounds 1-6 were mutagenic. Compound 8 gave erratic results. 4-(Acetoxymethyl)-2(5H)-furanone (11) was nonmutagenic. The largest drop in Mutagenicity amounted to a factor of about 10(2) for the replacement of the hydroxyl group or a C-3 chlorine atom from 3. Other replacements of the hydroxyl group or a C-3 or C-6 chlorine atom amounted to Mutagenicity diminished by a factor of only 10. On the basis of the rates of UV spectral changes under assay conditions, chemical half-life values (ct 1/2) for 1-6 and 8 were estimated as indicators of compound stability. However, Mutagenicity differences were shown to result principally from the intrinsic mutagenicities of the six compounds 1-6 rather than from differences in stability.(ABSTRACT TRUNCATED AT 250 WORDS)
Gisela De Aragao Umbuzeiro - One of the best experts on this subject based on the ideXlab platform.
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quantifying the contribution of dyes to the Mutagenicity of waters under the influence of textile activities
Science of The Total Environment, 2017Co-Authors: Francine Inforcato Vacchi, Josiane Aparecida De Souza Vendemiatti, Bianca Ferreira Da Silva, Maria Valnice Boldrin Zanoni, Gisela De Aragao UmbuzeiroAbstract:The combination of chemical analyses and bioassays allows the identification of potentially mutagenic compounds in different types of samples. Dyes can be considered as emergent contaminants and were detected in waters, under the influence of textile activities. The objective of this study was to evaluate the contribution of 9 azo dyes to the Mutagenicity of representative environmental samples. Samples were collected along one year in the largest conglomerate of textile industries of Brazil. We analyzed water samples from an important water body, Piracicaba River, upstream and downstream two main discharges, the effluent of a wastewater treatment plant (WWTP) and the tributary Quilombo River, which receives untreated effluent from local industries. Samples were analyzed using a LC-MS/MS and tested for Mutagenicity in the Salmonella/microsome microsuspension assay with TA98 and YG1041. Six dyes were detected in the collected samples, Disperse Blue 291, Disperse Blue 373, Disperse Orange 30, Disperse Red 1, Disperse Violet 93, and Disperse Yellow 3. The most sensitive condition for the detection of the Mutagenicity was the strain YG1041 with S9. The concentration of dyes and Mutagenicity levels varied along time and the dry season represented the worst condition. Disperse Blue 373 and Disperse Violet 93 were the major contributors to the Mutagenicity. We conclude that dyes are contributing for the Mutagenicity of Piracicaba River water; and both discharges, WWTP effluent and Quilombo River, increase the Mutagenicity of Piracicaba River waters in about 10-fold. The combination of chemical analysis and bioassays were key in the identification the main drivers of the water Mutagenicity and allows the selection of priority compounds to be included in monitoring programs as well for the enforcing actions required to protect the water quality for multiple uses.
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Mutagenicity profile of atmospheric particulate matter in a small urban center subjected to airborne emission from vehicle traffic and sugar cane burning
Environmental and Molecular Mutagenesis, 2016Co-Authors: Debora Kristina M Alves, Gisela De Aragao Umbuzeiro, Fabio Kummrow, Arnaldo Alves Cardoso, Daniel Alexandre MoralesAbstract:Atmospheric particulate matter (PM) is genotoxic and recently was classified as carcinogenic to humans by the International Agency for Research on Cancer. PM chemical composition varies depending on source and atmospheric conditions. The Salmonella/microsome assay is the most used Mutagenicity test and can identify the major chemical classes responsible for observed Mutagenicity. The objective of this work was to characterize the Mutagenicity of PM samples from a countryside city, Limeira, Brazil, which is influenced by heavy traffic and sugar cane biomass burning. Six samples of total PM were collected. Air mass backward trajectories were calculated. Organic extracts were assayed using the Salmonella/microsome microsuspension Mutagenicity assay using TA98, YG1041, and TA1538, with and without metabolic activation (S9). YG1041 was the most sensitive strain and Mutagenicity reached 9,700 revertants per m(3) without metabolic activation. Potency for TA1538 was higher than TA98, indicating that this strain should be considered in air Mutagenicity studies. The increased response to YG1041 relative to TA98, and the decreased response with S9, suggests that nitroaromatics are the major contributors. Limeira is among the most mutagenic cities in the world. High Mutagenicity in Limeira seems to occur when the air mass from the area of sugarcane production is mixed with air from the region impacted by anthropogenic activities such as traffic. An increase in the formation of nitro-polycyclic aromatic hydrocarbons may result from longer contact time between the aromatic compounds and the atmosphere with high NOx and ozone concentration, although more studies are required to confirm this hypothesis.
