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Detalles de la revista
Formato
Revista
eISSN
2719-9509
Publicado por primera vez
01 Jan 1992
Periodo de publicación
4 veces al año
Idiomas
Inglés

Buscar

Volumen 12 (1983): Edición 2 (June 1983)

Detalles de la revista
Formato
Revista
eISSN
2719-9509
Publicado por primera vez
01 Jan 1992
Periodo de publicación
4 veces al año
Idiomas
Inglés

Buscar

6 Artículos
Acceso abierto

Structural Study of Nicotine Salts

Publicado en línea: 14 Aug 2014
Páginas: 43 - 54

Resumen

Abstract

The structures of three types of nicotine salts have been determined. These salts have acid to base ratios of either 1 : 1, 2 : 1, or 3 : 1. Salt formation between organic acids and nicotine is dependent upon the structure of the acids (aliphatic or aromatic) and their functionality. The 1 : 1 salts of nicotine have amino acids or benzoic-type acids bound to the N-methylpyrrolidine nitrogen of nicotine. The 2 : 1 salts are found to bind to one acid group as in the 1 : 1 salts and a second to the nitrogen of the pyridine ring. The 2 : 1 salts of nicotine are formed with formic acid, aliphatic dicarboxylic acids, and/or nitroaromatic acids. Nicotine forms 3 : 1 salts with aliphatic monocarboxylic acids starting with acetic acid. Here one acid is bound as in the 1 : 1 salts while the other two acids dimerize and bind to the nitrogen of the pyridine group. Infra-red (IR), ultra-violet (UV), proton nuclear magnetic resonance (PMR), and carbon nuclear magnetic resonance (CMR) spectroscopy as well as field desorption - mass spectroscopy (FD-MS) were used in this investigation of the structure of nicotine salts.

Acceso abierto

The Effect of Some Nitrogenous Blend Components on NO/NOx and HCN Levels in Mainstream and Sidestream Smoke

Publicado en línea: 14 Aug 2014
Páginas: 55 - 62

Resumen

Abstract

Vapour phase NO concentrations in mainstream and sidestream smoke correlated well with blend nitrate levels over the range from 0.07 to 3.70 %. Native and added nitrate fit the same correlation. No measurable amounts of NO2 were detected in the vapour phase. When the mainstream and sidestream data were extrapolated to zero nitrate level, there remained a large residual amount of NO (approximately 100 µg /cig.) which could be attributed neither to nitrate nor to other nitrogenous blend components of the total volatile base type. Nitrogen-free cellulose cigarettes yielded of the order of 50 µg of NO per cigarette indicating that part of the residual NO probably arises from the oxidation of atmospheric nitrogen. The particulate phase contained small but measurable levels of nitrate which, with the exception of Mg(NO3) × 6 H2O added cigarettes, did not relate to blend nitrate levels. Mainstream vapour phase HCN level correlated weakly with blend nitrate levels but other nitrogenous materials whether native or added showed no clearly defined precursor-product relationship with smoke HCN yield. The partitioning of HCN between the vapour and particulate phases was not affected by any of the test variables.

Acceso abierto

The Distribution of Cigarette Smoke Components between Mainstream and Sidestream Smoke: I. Acidic Components

Publicado en línea: 14 Aug 2014
Páginas: 63 - 71

Resumen

Abstract

Yields in sidestream (SS) and mainstream (MS) smokes and sidestream to mainstream distribution ratios (SS/MS) of acidic components were examined for four types of cigarette made from bright, Burley, Turkish and domestic (c.v. Matsukawa) tobacco. Of the acidic components, formic and acetic acids were analysed by GC following n-butyl esterification, and acids other than formic and acetic acids and phenols similarly after trimethylsilylation. In acidic fractions of sidestream and mainstream smokes of four types of cigarettes, major phenolic components were phenol, catechol and hydroquinone, and major acids were formic, acetic, lactic, glycolic and succinic The following compounds gave SS/MS ratios > 1 for all types of cigarettes tested: phenol, cresols, xylenols, guaiacol, formic acid and acetic acid.

Acceso abierto

Study of the Action of Smoke on Alcohol Dehydrogenase, Lactic Dehydrogenase and Malate Dehydrogenase Enzymes

Publicado en línea: 14 Aug 2014
Páginas: 73 - 79

Resumen

Abstract

The aim of this study is to acquire better knowledge of the action of the whole smoke and the vapour phase on alcohol dehydrogenase (ADH), lactic dehydrogenase (LDH), and malate dehydrogenase (MDH). The method developed provides that smoke comes into direct contact with the various enzymatic solutions without any preventive extraction, as in previous methods. It is based on the determination of the degree of inhibition of sulfhydryl reagent groups of enzyme by smoke. Additionally, the efficiency of cigarette filters for the reduction of this inhibition was evaluated. The purpose of this study also included the examination of the protective effect of thiol groups of enzymes against the inhibitory action of smoke. The results obtained show a high reactivity of smoke with sulfhydrylic groups of the enzymes examined. The effect of this reactivity is different for the three enzymes considered and dependent upon the role that sulfhydryl reagent groups had in the enzymatic activity. In particular, it was found that alcohol dehydrogenase, which needs all its sulfhydryl groups for its own activity, undergoes a strong inhibition due to smoke, while lactic dehydrogenase shows a negligible inhibition. The tests made have also shown the protective action of thiol on the inhibited enzymes.

Acceso abierto

Determination of the Antioxidant Properties of Tobacco Smoke by Cytochrome C

Publicado en línea: 14 Aug 2014
Páginas: 81 - 85

Resumen

Abstract

The reduction of cytochrome c was taken as an index of the antioxidant activity of the whole smoke and the vapour phase. The method developed consists in the determination of the antioxidant activity in smoke by spectrophotometric and potentiometric determinations. Cigarette smoke was placed in direct contact with the buffer solution of the cytochrome c, thus avoiding the collection and extraction necessitated by other systems. The antioxidant activity of smoke was determined by spectrophotometric analysis as a function of thee variation in the absorption value of 550 nm caused by the reduced cytochrome, while the potentiometric analysis determines the rapid decrease in the reduction potential. The data obtained by these two methods corresponded perfectly with each other and they also showed that the above methods were reliable as an index of the antioxidant activity of smoke. Reduction of cytochrome in the smoke of ventilated cigarettes shows a difference in the vapour phase and not in the whole smoke.

Acceso abierto

Determination of Aldicarb Residues in Tobacco/Bestimmung von Aldicarb-Rückständen in Tabak

Publicado en línea: 14 Aug 2014
Páginas: 87 - 91

Resumen

Abstract

To supplement known gas chromatographic processes for determining the residues of the aldicarb pesticide in tobacco, we have developed a method which makes use of high-pressure liquid chromatography. This is of particular importance inasmuch as the German Law on Pesticides provides for a maximum amount of aldicarb in tobacco.

6 Artículos
Acceso abierto

Structural Study of Nicotine Salts

Publicado en línea: 14 Aug 2014
Páginas: 43 - 54

Resumen

Abstract

The structures of three types of nicotine salts have been determined. These salts have acid to base ratios of either 1 : 1, 2 : 1, or 3 : 1. Salt formation between organic acids and nicotine is dependent upon the structure of the acids (aliphatic or aromatic) and their functionality. The 1 : 1 salts of nicotine have amino acids or benzoic-type acids bound to the N-methylpyrrolidine nitrogen of nicotine. The 2 : 1 salts are found to bind to one acid group as in the 1 : 1 salts and a second to the nitrogen of the pyridine ring. The 2 : 1 salts of nicotine are formed with formic acid, aliphatic dicarboxylic acids, and/or nitroaromatic acids. Nicotine forms 3 : 1 salts with aliphatic monocarboxylic acids starting with acetic acid. Here one acid is bound as in the 1 : 1 salts while the other two acids dimerize and bind to the nitrogen of the pyridine group. Infra-red (IR), ultra-violet (UV), proton nuclear magnetic resonance (PMR), and carbon nuclear magnetic resonance (CMR) spectroscopy as well as field desorption - mass spectroscopy (FD-MS) were used in this investigation of the structure of nicotine salts.

Acceso abierto

The Effect of Some Nitrogenous Blend Components on NO/NOx and HCN Levels in Mainstream and Sidestream Smoke

Publicado en línea: 14 Aug 2014
Páginas: 55 - 62

Resumen

Abstract

Vapour phase NO concentrations in mainstream and sidestream smoke correlated well with blend nitrate levels over the range from 0.07 to 3.70 %. Native and added nitrate fit the same correlation. No measurable amounts of NO2 were detected in the vapour phase. When the mainstream and sidestream data were extrapolated to zero nitrate level, there remained a large residual amount of NO (approximately 100 µg /cig.) which could be attributed neither to nitrate nor to other nitrogenous blend components of the total volatile base type. Nitrogen-free cellulose cigarettes yielded of the order of 50 µg of NO per cigarette indicating that part of the residual NO probably arises from the oxidation of atmospheric nitrogen. The particulate phase contained small but measurable levels of nitrate which, with the exception of Mg(NO3) × 6 H2O added cigarettes, did not relate to blend nitrate levels. Mainstream vapour phase HCN level correlated weakly with blend nitrate levels but other nitrogenous materials whether native or added showed no clearly defined precursor-product relationship with smoke HCN yield. The partitioning of HCN between the vapour and particulate phases was not affected by any of the test variables.

Acceso abierto

The Distribution of Cigarette Smoke Components between Mainstream and Sidestream Smoke: I. Acidic Components

Publicado en línea: 14 Aug 2014
Páginas: 63 - 71

Resumen

Abstract

Yields in sidestream (SS) and mainstream (MS) smokes and sidestream to mainstream distribution ratios (SS/MS) of acidic components were examined for four types of cigarette made from bright, Burley, Turkish and domestic (c.v. Matsukawa) tobacco. Of the acidic components, formic and acetic acids were analysed by GC following n-butyl esterification, and acids other than formic and acetic acids and phenols similarly after trimethylsilylation. In acidic fractions of sidestream and mainstream smokes of four types of cigarettes, major phenolic components were phenol, catechol and hydroquinone, and major acids were formic, acetic, lactic, glycolic and succinic The following compounds gave SS/MS ratios > 1 for all types of cigarettes tested: phenol, cresols, xylenols, guaiacol, formic acid and acetic acid.

Acceso abierto

Study of the Action of Smoke on Alcohol Dehydrogenase, Lactic Dehydrogenase and Malate Dehydrogenase Enzymes

Publicado en línea: 14 Aug 2014
Páginas: 73 - 79

Resumen

Abstract

The aim of this study is to acquire better knowledge of the action of the whole smoke and the vapour phase on alcohol dehydrogenase (ADH), lactic dehydrogenase (LDH), and malate dehydrogenase (MDH). The method developed provides that smoke comes into direct contact with the various enzymatic solutions without any preventive extraction, as in previous methods. It is based on the determination of the degree of inhibition of sulfhydryl reagent groups of enzyme by smoke. Additionally, the efficiency of cigarette filters for the reduction of this inhibition was evaluated. The purpose of this study also included the examination of the protective effect of thiol groups of enzymes against the inhibitory action of smoke. The results obtained show a high reactivity of smoke with sulfhydrylic groups of the enzymes examined. The effect of this reactivity is different for the three enzymes considered and dependent upon the role that sulfhydryl reagent groups had in the enzymatic activity. In particular, it was found that alcohol dehydrogenase, which needs all its sulfhydryl groups for its own activity, undergoes a strong inhibition due to smoke, while lactic dehydrogenase shows a negligible inhibition. The tests made have also shown the protective action of thiol on the inhibited enzymes.

Acceso abierto

Determination of the Antioxidant Properties of Tobacco Smoke by Cytochrome C

Publicado en línea: 14 Aug 2014
Páginas: 81 - 85

Resumen

Abstract

The reduction of cytochrome c was taken as an index of the antioxidant activity of the whole smoke and the vapour phase. The method developed consists in the determination of the antioxidant activity in smoke by spectrophotometric and potentiometric determinations. Cigarette smoke was placed in direct contact with the buffer solution of the cytochrome c, thus avoiding the collection and extraction necessitated by other systems. The antioxidant activity of smoke was determined by spectrophotometric analysis as a function of thee variation in the absorption value of 550 nm caused by the reduced cytochrome, while the potentiometric analysis determines the rapid decrease in the reduction potential. The data obtained by these two methods corresponded perfectly with each other and they also showed that the above methods were reliable as an index of the antioxidant activity of smoke. Reduction of cytochrome in the smoke of ventilated cigarettes shows a difference in the vapour phase and not in the whole smoke.

Acceso abierto

Determination of Aldicarb Residues in Tobacco/Bestimmung von Aldicarb-Rückständen in Tabak

Publicado en línea: 14 Aug 2014
Páginas: 87 - 91

Resumen

Abstract

To supplement known gas chromatographic processes for determining the residues of the aldicarb pesticide in tobacco, we have developed a method which makes use of high-pressure liquid chromatography. This is of particular importance inasmuch as the German Law on Pesticides provides for a maximum amount of aldicarb in tobacco.

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