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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 6 (1972): Edición 3 (March 1972)

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

13 Artículos
Acceso abierto

Relation of Wood Colour in Burley Tobacco Stalks to Nicotine Content of the Leaves

Publicado en línea: 19 Jul 2014
Páginas: 93 - 95

Resumen

Abstract

The colour of Burley tobacco stalks was found to be correlated with nicotine content of the leaves. The wood varies from oyster white to pumpkin in colour; the lighter the coloUr the less nicotine. Correlation coefficients between wood colour index and percent nicotine ranged between .81 and .84 which was highly significant at the .01 Ievel of probability. These results indicate that percent nicotine in Burley tobacco can be reliably estimated by using the simple, rapid, and wood in inexpensive wood colour index for classification of plants. Colour photographs to illustrate these differences are included

Acceso abierto

Tobacco Chemistry: 8: Chemical and Ciliotoxic Studies of Smoke from Heat-Treated Tobacco

Publicado en línea: 19 Jul 2014
Páginas: 96 - 105

Resumen

Abstract

Heat-treated and corresponding conventionally cured tobacco have been subjected to comparative studies. The heat-treating process has been carried out under laboratory and curing barn conditions. Analyses of the three different tobaccos show that the heat treatment leads to a considerable reduction of the polyphenols and a less pronounced reduction of nicotine. Determinations of the amount of total particulate matter, dry condensate, nicotine, and "phenol" in the smoke from cigarettes manufactured from the three types of tobaccos show that the heat treatment in the barn gives rise to a small but relevant lowering of these values. Examination of the ciliotoxic effect of the smokes on rabbit trachea in vitro reveals that there is a significant, although moderate, difference between the tobacco heat-treated in the laboratory and the control as regards the number of puffs required to achieve complete ciliostasis. A detailed gas chromatographic-mass spectrometric study using a high resolution glass capillary column and computerised data-acquisition demonstrates the absence of significant differences in the gas phases of the smoke derived from the differently treated tobaccos.

Acceso abierto

Chromatographic Examinations on the Separation of the Alkylating Fractions of Cigarette Tobacco and Smoke/Chromatographische Untersuchungen zur Auftrennung alkylierender Fraktionen des Cigarettentabaks und des Cigarettenrauches

Publicado en línea: 19 Jul 2014
Páginas: 106 - 116

Resumen

Abstract

In order to obtain information about number and origin of compounds which may contribute to the alkylating activity of tobacco smoke condensate identifiable in the methanol extract of the condensate of commerciaI cigarettes by means of 4-(4'-nitrobenzyI)pyridine, spectroscopic as well as thin-layer- and column-chromatographic procedures were used. Two compounds of the water- or methanoI-soluble fraction were separated and proved to be resorbed during inhalation and dissolved in saliva. During the process of conventional condensate treatment, further five less polaric compounds were found to remain in the cyclohexane fraction, whereas the resulting nitromethane fraction contains the carcinogenic activity almost totally. These compounds can also be extracted from unsmoked tobacco. The role they possibly play in respiratory carcinogenesis is discussed on the basis of the results obtained by the present study with regard to carcinogenic constituents of tobacco extracts.

Acceso abierto

The Possible Occurrence of Nitrosamines in Tobacco Smoke

Publicado en línea: 19 Jul 2014
Páginas: 117 - 119

Resumen

Abstract

Attempts were made to demonstrate the presence of N-nitrosamines in tobacco smoke with and without the addition of dimethyl-N-nitrosamine (DMNA) to the smoke stream. In recovery experiments, DMNA, in aqueous solution added to the smoke stream, was recovered to 80 % down to 20 µg, in the presence of the smoke constituents of 50 cigarettes. Extensive Iosses were encountered when organic solvents were used. Up to 500 cigarettes were smoked in one run. In no case could the presence of coloured acyl derivatives corresponding to known nitrosamines be demonstrated. However, in these cases, presence of coloured compounds of non-nitrosamine origin interfered with the estimation of DMNA. It is concluded that nitrosamines do not occur in cigarette smoke in amounts higher than 50 ng per cigarette, and that the actual amounts are probably even lower corresponding to previous reports. The stability of nitrosamines in different solvents will be investigated in some future experiments.

Acceso abierto

Composition Studies on Tobacco: XLV. Use of Cigarette Additives to Alter the Composition and Reducing Properties of Cigarette Smoke

Publicado en línea: 19 Jul 2014
Páginas: 120 - 123

Resumen

Abstract

The reducing potential of fresh cigarette smoke can be modified by the use of certain oxidants and reductants. The influence of these additives on smoke may be monitored by employing a system which measures changes in EMF on a puff by puff basis. The addition of the oxidant 1,4-benzoquinone to tobacco eliminates the rapid reduction in potential which normally takes place when an untreated cigarette is smoked. The addition of the benzoquinone alters the composition of the smoke by increasing the levels of the total particulate matter and possibly the phenols, while decreasing the nicotine content without affecting the amount of benzo[a]pyrene formed. The addition of sodium thiosulfate to tobacco causes a significant increase in the reducing capacity of cigarette smoke. It also brings about increases in the smoke BAP, phenols and TPM. The level of nicotine in these cigarettes, however, is lowered.

Acceso abierto

The Determination of Menthol in Tobacco, in Filters and in the Smoke of Mentholated Cigarettes/Untersuchungen über die Verteilung des Menthols auf Tabak, Filter und Rauch von Mentholcigaretten

Publicado en línea: 19 Jul 2014
Páginas: 124 - 130

Resumen

Abstract

A method for the determination of menthol in tobacco, in filters before and after smoking as well as in the smoke of mentholated cigarettes is presented which is based on the combination of steam distillation and liquid-Iiquid partition followed by gas chromatography on polypropylene glycol in the presence of benzylpropionate as an internal standard. The procedure also permits menthone to be quantitatively determined as a characteristic constituent of peppermint oils. Analytical results concerning reproducibility, recovery and sensitivity of the method are detailed. The transfer of menthol from the tobacco rod to the acetate filter and vice versa as a function of the storing period of mentholated cigarettes has been investigated as well as the menthol distribution due to the smoking process. A considerable selective retention of menthol by cellulose acetate filters could be demonstrated. Various mentholated cigarettes of different origin and of different menthol contents have comparatively been analysed.

Acceso abierto

The Determination of Tobacco Additives 2nd Report: A Method for Series Analyses of Menthol in Tobacco and Tobacco Products/Zur Bestimmung von Tabakadditiven: 2. Mitteilung: Eine Methode zur serienanalytischen Bestimmung von Menthol in Tabak und Tabakerzeugnissen

Publicado en línea: 19 Jul 2014
Páginas: 131 - 133

Resumen

Abstract

The method used in our laboratories since 1965 for the determination of menthol in tobacco and tobacco products has meanwhile been improved and made suitable for series analyses. Menthol is isolated from the mentholated material to be investigated by steam distillation The distillate containing the menthol in question (dissolved in acetone) is directly subjected to gas chromatography for quantitative determination. The recovery was found to amount to 97 %, the coefficient of variation to 1.45 %, and the detection limit to 0.002 mg of menthol per mI.

Acceso abierto

Characteristic Products from Pyrolysis of Nitrogenous Organic Substances

Publicado en línea: 19 Jul 2014
Páginas: 134 - 138

Resumen

Abstract

The products resulting from the pyrolysis of tobacco and a number of nitrogenous organic compounds similar, if not identical, to those found in tobacco have been compared. Similarities have been noted in the composition of the various pyrolyzates, but essentially no physiologically active materials were found. Generalities with regard to pyrolysis of nitrogenous organic substances have been suggested by the data assembled.

Acceso abierto

Systematic Studies on the Breakdown of p,p’-DDT in Tobacco Smokes: III. Isolation and Identification of the Non-Volatile Degradation Products of p,p’-DDT in p,p’-DDT-Treated Tobacco Smokes

Publicado en línea: 19 Jul 2014
Páginas: 139 - 143

Resumen

Abstract

This paper describes the methods used in smoking p,p'-DDT-treated tobacco, collecting the smoke condensate, chromatographing the condensate on activated Florisil and deactivated alumina columns, and finally identifying the non-volatile p,p'-DDT pyrolysis products in the tobacco smoke condensate. The pyrolysis products identified were: p,p'-DDT, p,p'- DDE, p,p'-TDE, p,p'-DDM, trans-p,p'-dichlorostilbene, bis-(p-chlorophenyI)methane, and p,p'-dichlorobenzophenone.

Acceso abierto

Pesticide Residues in Rhodesian Tobacco Attributable to Recommended Pest Control Practices

Publicado en línea: 19 Jul 2014
Páginas: 144 - 147

Resumen

Abstract

The use of pesticides on tobacco in Rhodesia is controlled by legislation that prevents the sale of tobacco treated with unscheduled pesticides. Residues attributable to seedbed treatments have not been studied in detaiI; the scheduled pesticides that can be applied to the soil and the leaf in the field have been considered more fully. Although no longer permitted for use, aldrin and dieldrin soil residues from previous treatments are more persistent in tropical sandy soils than in soils of the temperate regions and small amounts of background dieldrin are taken up by tobacco grown in these soils. Uptake of DDT is negligible and very little disulfoton or menazon applied to the soil is found in cured leaf. The pesticides that are permitted for application to the leaf result in residues of Iess than 1 ppm except menazon which results in a residue of up to 5 ppm.

Acceso abierto

Effects of irrigation, Nitrogen Fertilization, Plant Population and Variety on the Physico-Chemical Properties of Maryland Tobacco: I. Agronomic Effects

Publicado en línea: 19 Jul 2014
Páginas: 148 - 160

Resumen

Abstract

Irrigation experiments on Maryland tobacco have been conducted since 1955 on Monmouth fine sandy loam, a typical tobacco soil of Southern Maryland. An overhead sprinkler system was employed. Moisture levels in the soil were studied, using Bouyoucous gypsum blocks and tensiometers. The following conclusions were made from this study:

1. In a year of severe drought, 1966, ample irrigation increased yields, unit value and total value. Irrigated yields were 175 per cent of non-irrigated; unit value was 141 per cent, and total value of irrigated tobacco was 247 per cent of non-irrigated.

2. Nitrogen fertilizer rates of 100.9, 134.5 and 168.1 kg ha were used. Under irrigation, gains in yield and total value, and some loss in unit value were obtained from the first added increment of fertilizer nitrogen above the base amount. Addition of the second increment produced smaller gains in yield, a greater loss in unit value, and losses in total value.

3. In the absence of irrigation, the supply of soil water could limit nitrogen assimilation by the plants. The higher rates of nitrogen fertilization were effective in increasing yield and total value over the lower increments. Even unit value was not adversely affected.

4. The Wilson broadleaf variety of Maryland tobacco consistently outyielded the Catterton medium broadleaf variety, but due to lower unit value, probably caused by darker colours, it had a lower total value.

5. Plant populations of about 18000 per hectare produced increased yields and gross return over a population of about 12000. Populations of 24000 plants per hectare were excessive in most cases, and produced losses in yield and unit value.

6. Comparative response to irrigation depends on severity of drought, but late depletion of soil moisture levels may prevent the full potential development of the crop, and result in lower yields and total value.

Acceso abierto

Microscopic Examination of Fibres Used for the Manufacture of Cigarette Papers/Mikroskopische Untersuchungen zur Stoffzusammensetzung von Cigarettenpapieren

Publicado en línea: 19 Jul 2014
Páginas: 161 - 164

Resumen

Abstract

The present paper shows and discusses microphotographs of fibres used for the manufacture of cigarette papers as well as such photographs disclosing the composition of cigarette papers.

Acceso abierto

Measurement of paper porosity

Publicado en línea: 19 Jul 2014
Páginas: 165 - 165

Resumen

Abstract

The author's supplementary comment on the original publication which apeared on pp. 307 to 311 of volume 5 of the “Beiträge zur Tabakforschung” (1969-1970).

13 Artículos
Acceso abierto

Relation of Wood Colour in Burley Tobacco Stalks to Nicotine Content of the Leaves

Publicado en línea: 19 Jul 2014
Páginas: 93 - 95

Resumen

Abstract

The colour of Burley tobacco stalks was found to be correlated with nicotine content of the leaves. The wood varies from oyster white to pumpkin in colour; the lighter the coloUr the less nicotine. Correlation coefficients between wood colour index and percent nicotine ranged between .81 and .84 which was highly significant at the .01 Ievel of probability. These results indicate that percent nicotine in Burley tobacco can be reliably estimated by using the simple, rapid, and wood in inexpensive wood colour index for classification of plants. Colour photographs to illustrate these differences are included

Acceso abierto

Tobacco Chemistry: 8: Chemical and Ciliotoxic Studies of Smoke from Heat-Treated Tobacco

Publicado en línea: 19 Jul 2014
Páginas: 96 - 105

Resumen

Abstract

Heat-treated and corresponding conventionally cured tobacco have been subjected to comparative studies. The heat-treating process has been carried out under laboratory and curing barn conditions. Analyses of the three different tobaccos show that the heat treatment leads to a considerable reduction of the polyphenols and a less pronounced reduction of nicotine. Determinations of the amount of total particulate matter, dry condensate, nicotine, and "phenol" in the smoke from cigarettes manufactured from the three types of tobaccos show that the heat treatment in the barn gives rise to a small but relevant lowering of these values. Examination of the ciliotoxic effect of the smokes on rabbit trachea in vitro reveals that there is a significant, although moderate, difference between the tobacco heat-treated in the laboratory and the control as regards the number of puffs required to achieve complete ciliostasis. A detailed gas chromatographic-mass spectrometric study using a high resolution glass capillary column and computerised data-acquisition demonstrates the absence of significant differences in the gas phases of the smoke derived from the differently treated tobaccos.

Acceso abierto

Chromatographic Examinations on the Separation of the Alkylating Fractions of Cigarette Tobacco and Smoke/Chromatographische Untersuchungen zur Auftrennung alkylierender Fraktionen des Cigarettentabaks und des Cigarettenrauches

Publicado en línea: 19 Jul 2014
Páginas: 106 - 116

Resumen

Abstract

In order to obtain information about number and origin of compounds which may contribute to the alkylating activity of tobacco smoke condensate identifiable in the methanol extract of the condensate of commerciaI cigarettes by means of 4-(4'-nitrobenzyI)pyridine, spectroscopic as well as thin-layer- and column-chromatographic procedures were used. Two compounds of the water- or methanoI-soluble fraction were separated and proved to be resorbed during inhalation and dissolved in saliva. During the process of conventional condensate treatment, further five less polaric compounds were found to remain in the cyclohexane fraction, whereas the resulting nitromethane fraction contains the carcinogenic activity almost totally. These compounds can also be extracted from unsmoked tobacco. The role they possibly play in respiratory carcinogenesis is discussed on the basis of the results obtained by the present study with regard to carcinogenic constituents of tobacco extracts.

Acceso abierto

The Possible Occurrence of Nitrosamines in Tobacco Smoke

Publicado en línea: 19 Jul 2014
Páginas: 117 - 119

Resumen

Abstract

Attempts were made to demonstrate the presence of N-nitrosamines in tobacco smoke with and without the addition of dimethyl-N-nitrosamine (DMNA) to the smoke stream. In recovery experiments, DMNA, in aqueous solution added to the smoke stream, was recovered to 80 % down to 20 µg, in the presence of the smoke constituents of 50 cigarettes. Extensive Iosses were encountered when organic solvents were used. Up to 500 cigarettes were smoked in one run. In no case could the presence of coloured acyl derivatives corresponding to known nitrosamines be demonstrated. However, in these cases, presence of coloured compounds of non-nitrosamine origin interfered with the estimation of DMNA. It is concluded that nitrosamines do not occur in cigarette smoke in amounts higher than 50 ng per cigarette, and that the actual amounts are probably even lower corresponding to previous reports. The stability of nitrosamines in different solvents will be investigated in some future experiments.

Acceso abierto

Composition Studies on Tobacco: XLV. Use of Cigarette Additives to Alter the Composition and Reducing Properties of Cigarette Smoke

Publicado en línea: 19 Jul 2014
Páginas: 120 - 123

Resumen

Abstract

The reducing potential of fresh cigarette smoke can be modified by the use of certain oxidants and reductants. The influence of these additives on smoke may be monitored by employing a system which measures changes in EMF on a puff by puff basis. The addition of the oxidant 1,4-benzoquinone to tobacco eliminates the rapid reduction in potential which normally takes place when an untreated cigarette is smoked. The addition of the benzoquinone alters the composition of the smoke by increasing the levels of the total particulate matter and possibly the phenols, while decreasing the nicotine content without affecting the amount of benzo[a]pyrene formed. The addition of sodium thiosulfate to tobacco causes a significant increase in the reducing capacity of cigarette smoke. It also brings about increases in the smoke BAP, phenols and TPM. The level of nicotine in these cigarettes, however, is lowered.

Acceso abierto

The Determination of Menthol in Tobacco, in Filters and in the Smoke of Mentholated Cigarettes/Untersuchungen über die Verteilung des Menthols auf Tabak, Filter und Rauch von Mentholcigaretten

Publicado en línea: 19 Jul 2014
Páginas: 124 - 130

Resumen

Abstract

A method for the determination of menthol in tobacco, in filters before and after smoking as well as in the smoke of mentholated cigarettes is presented which is based on the combination of steam distillation and liquid-Iiquid partition followed by gas chromatography on polypropylene glycol in the presence of benzylpropionate as an internal standard. The procedure also permits menthone to be quantitatively determined as a characteristic constituent of peppermint oils. Analytical results concerning reproducibility, recovery and sensitivity of the method are detailed. The transfer of menthol from the tobacco rod to the acetate filter and vice versa as a function of the storing period of mentholated cigarettes has been investigated as well as the menthol distribution due to the smoking process. A considerable selective retention of menthol by cellulose acetate filters could be demonstrated. Various mentholated cigarettes of different origin and of different menthol contents have comparatively been analysed.

Acceso abierto

The Determination of Tobacco Additives 2nd Report: A Method for Series Analyses of Menthol in Tobacco and Tobacco Products/Zur Bestimmung von Tabakadditiven: 2. Mitteilung: Eine Methode zur serienanalytischen Bestimmung von Menthol in Tabak und Tabakerzeugnissen

Publicado en línea: 19 Jul 2014
Páginas: 131 - 133

Resumen

Abstract

The method used in our laboratories since 1965 for the determination of menthol in tobacco and tobacco products has meanwhile been improved and made suitable for series analyses. Menthol is isolated from the mentholated material to be investigated by steam distillation The distillate containing the menthol in question (dissolved in acetone) is directly subjected to gas chromatography for quantitative determination. The recovery was found to amount to 97 %, the coefficient of variation to 1.45 %, and the detection limit to 0.002 mg of menthol per mI.

Acceso abierto

Characteristic Products from Pyrolysis of Nitrogenous Organic Substances

Publicado en línea: 19 Jul 2014
Páginas: 134 - 138

Resumen

Abstract

The products resulting from the pyrolysis of tobacco and a number of nitrogenous organic compounds similar, if not identical, to those found in tobacco have been compared. Similarities have been noted in the composition of the various pyrolyzates, but essentially no physiologically active materials were found. Generalities with regard to pyrolysis of nitrogenous organic substances have been suggested by the data assembled.

Acceso abierto

Systematic Studies on the Breakdown of p,p’-DDT in Tobacco Smokes: III. Isolation and Identification of the Non-Volatile Degradation Products of p,p’-DDT in p,p’-DDT-Treated Tobacco Smokes

Publicado en línea: 19 Jul 2014
Páginas: 139 - 143

Resumen

Abstract

This paper describes the methods used in smoking p,p'-DDT-treated tobacco, collecting the smoke condensate, chromatographing the condensate on activated Florisil and deactivated alumina columns, and finally identifying the non-volatile p,p'-DDT pyrolysis products in the tobacco smoke condensate. The pyrolysis products identified were: p,p'-DDT, p,p'- DDE, p,p'-TDE, p,p'-DDM, trans-p,p'-dichlorostilbene, bis-(p-chlorophenyI)methane, and p,p'-dichlorobenzophenone.

Acceso abierto

Pesticide Residues in Rhodesian Tobacco Attributable to Recommended Pest Control Practices

Publicado en línea: 19 Jul 2014
Páginas: 144 - 147

Resumen

Abstract

The use of pesticides on tobacco in Rhodesia is controlled by legislation that prevents the sale of tobacco treated with unscheduled pesticides. Residues attributable to seedbed treatments have not been studied in detaiI; the scheduled pesticides that can be applied to the soil and the leaf in the field have been considered more fully. Although no longer permitted for use, aldrin and dieldrin soil residues from previous treatments are more persistent in tropical sandy soils than in soils of the temperate regions and small amounts of background dieldrin are taken up by tobacco grown in these soils. Uptake of DDT is negligible and very little disulfoton or menazon applied to the soil is found in cured leaf. The pesticides that are permitted for application to the leaf result in residues of Iess than 1 ppm except menazon which results in a residue of up to 5 ppm.

Acceso abierto

Effects of irrigation, Nitrogen Fertilization, Plant Population and Variety on the Physico-Chemical Properties of Maryland Tobacco: I. Agronomic Effects

Publicado en línea: 19 Jul 2014
Páginas: 148 - 160

Resumen

Abstract

Irrigation experiments on Maryland tobacco have been conducted since 1955 on Monmouth fine sandy loam, a typical tobacco soil of Southern Maryland. An overhead sprinkler system was employed. Moisture levels in the soil were studied, using Bouyoucous gypsum blocks and tensiometers. The following conclusions were made from this study:

1. In a year of severe drought, 1966, ample irrigation increased yields, unit value and total value. Irrigated yields were 175 per cent of non-irrigated; unit value was 141 per cent, and total value of irrigated tobacco was 247 per cent of non-irrigated.

2. Nitrogen fertilizer rates of 100.9, 134.5 and 168.1 kg ha were used. Under irrigation, gains in yield and total value, and some loss in unit value were obtained from the first added increment of fertilizer nitrogen above the base amount. Addition of the second increment produced smaller gains in yield, a greater loss in unit value, and losses in total value.

3. In the absence of irrigation, the supply of soil water could limit nitrogen assimilation by the plants. The higher rates of nitrogen fertilization were effective in increasing yield and total value over the lower increments. Even unit value was not adversely affected.

4. The Wilson broadleaf variety of Maryland tobacco consistently outyielded the Catterton medium broadleaf variety, but due to lower unit value, probably caused by darker colours, it had a lower total value.

5. Plant populations of about 18000 per hectare produced increased yields and gross return over a population of about 12000. Populations of 24000 plants per hectare were excessive in most cases, and produced losses in yield and unit value.

6. Comparative response to irrigation depends on severity of drought, but late depletion of soil moisture levels may prevent the full potential development of the crop, and result in lower yields and total value.

Acceso abierto

Microscopic Examination of Fibres Used for the Manufacture of Cigarette Papers/Mikroskopische Untersuchungen zur Stoffzusammensetzung von Cigarettenpapieren

Publicado en línea: 19 Jul 2014
Páginas: 161 - 164

Resumen

Abstract

The present paper shows and discusses microphotographs of fibres used for the manufacture of cigarette papers as well as such photographs disclosing the composition of cigarette papers.

Acceso abierto

Measurement of paper porosity

Publicado en línea: 19 Jul 2014
Páginas: 165 - 165

Resumen

Abstract

The author's supplementary comment on the original publication which apeared on pp. 307 to 311 of volume 5 of the “Beiträge zur Tabakforschung” (1969-1970).

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