bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improved Method for the Determination of Tobacco-specific Nitrosamines (TSNA) in Tobacco Smoke
Authors: Fischer S , Spiegelhalder B 
Published: July 2016

Abstract
The method used to determine tobacco-specific nitrosamines [TSNA], N’-nitrosonornicotine [NNN], 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone [NNK], N’-nitrosoanabasine [NAB] and N’-nitrosoanatabine [NAT], in mainstream smoke was modified. The methodology included trapping mainstream smoke in a buffer solution and on a Cambridge filter, extracting TSNA from the buffer solution and the filter with dichloromethane, clean-up procedures and analysis by GC/TEA. Extracts from both the buffer solution and the filter were cleaned up and analysed individually. The clean-up procedure included column chromatography on basic alumina and the removal of nicotine. N-Nitrosodibenzylamine [NDBenzA] which had suitable chromatographic properties was used as internal standard. N’-Nitrosopentylpicolylamine [NPePicA], a newly synthesized nitrosamine with physicochemical properties similar to the TSNA, could also be used as an internal standard. The recoveries for the buffer solution were as follows: NDBenzA 89 %, NPePicA 83 %, NNN 85 %, NNK 88 %, NAB/NAT 85 %. For the TSNA trapped on the filter the following recoveries were determined: NDBenzA 81 %, NPePicA 75 %, NNN 77 %, NNK 78 %, NAB/NAT 75 %. Parameters influencing the TSNA values in the mainstream smoke were investigated. Artifact formation of TSNA during mainstream smoke collection did not occur under standard conditions. TSNA values were greatly influenced by the puff volume, they increased with increasing puff volume. Reproducible and reliable results can be achieved in a relatively short time with the method reported.
Physiology and Biochemistry of the Tobacco Plant. 1. Growth and Development - Physiologie und Biochemie der Tabakpflanze: 1. Wachstum und Entwicklung
Authors: Bush LP , Tso TC 
Published: July 2016

Abstract
Growth and development processes of a tobacco plant affect the chemical composition of the leaf and therefore the usability of the leaf. Growth starts with the initial stages of germination and development stops with the cured leaf. Most tobacco seed will germinate in the dark and the first seeds to germinate from a seed lot tend to produce larger plants for transplant and harvest. Nicotine is found in mature seed and increased rate of germination increases rate of nicotine accumulation in the young seedling. Carbon / nitrogen balance in the leaf is important for leaf usability and is influenced by available soil water and soil nitrogen. Oriental leaf is produced typically with limited water and nitrogen supply and the leaf contains large amounts of carbohydrates and ether solubles but small amounts of nitrogenous substances. Cigar filler tobacco is grown on soils with a plentiful supply of soil water and soil nitrogen and the leaf contains large amounts of nitrogenous substances. Intermediate to these tobacco types is flue-cured tobacco which is grown with limited soil nirogen but adequate water and the leaf is relatively thin with high carbohydrate content. Maximum rate of leaf expansion is achieved early in development of a leaf. In flue-cured tobacco phosphorus and potassium concentrations remain constant during growth, whereas nitrogen, calcium and magnesium concentrations decrease. In Oriental tobacco the concentrations of nitrogen, phosphorus, potassium and calcium decrease during the growing season. However, Burley tobacco accumulates relatively greater amounts of nitrogen, phosphorus and potassium during the first half of the growing season relative to dry matter accumulation. Maximum growth per unit leaf weight occurs 14 to 21 days after transplanting, whereas maximum dry matter accumulation per day occurs 50 to 55 days after transplanting. Leaf development including senescence is controlled genetically and decreased chlorophyll and protein and increased nicotine contents are important changes associated with leaf senescence. Maximum nicotine content of leaf occurs at successively higher stalk positions as the plant matures.
Changes in the Cellular Concentrations of Elements in Tobacco Leaf Tissues during Growth and Senescence
Authors: Echlin P 
Published: July 2016

Abstract
Quantitative X-ray microanalysis for nine elements has been carried out on frozen, fully hydrated fracture faces of upper and lower epidermis, palisade and spongy mesophyll cells in leaf tissue of Nicotianatabacum L. cv. Coker 319 taken from plants at five different stages of growth. Although concentrations of aluminium, silicon and chlorine generally fell below the minimum-detection limit, the values for sodium, magnesium, phosphorus, sulphur, potassium and calcium were consistently higher and showed differences among tissue types and stages of growth. The general trend was for elemental concentrations to increase up to the mature and ripe stages of growth and then to decrease as the leaf ages further. The sodium values were highest at the beginning and end of the five stages of growth, with higher amounts in the epidermal tissues. As the leaves age, the levels of magnesium fell in the photosynthetic tissues but increased in the epidermal tissues. Such changes could be correlated with higher concentrations of potassium at the early stages of growth and with much lower values at the late stages. The sulphur levels showed only small differences between tissue types at all stages of growth. The calcium levels increased with age and there were consistently higher concentrations in the photosynthetic tissues than in the two epidermal layers. The levels of phosphorus were low in all tissue types and decreased with age. There is an increasing positive correlation between phosphorus and magnesium and a decreasing positive correlation between phosphorus and potassium during growth and senescence.
Effects of Curing and Fertilization on Nitrosamine Formation in Bright and Burley Tobacco
Authors: Chamberlain WJ , Chortyk OT 
Published: July 2016

Abstract
A bright and a Burley tobacco were grown at four fertilization rates and each tobacco was then both flue-cured and air-cured. Levels of alkaloids and nitrosamines were found to increase with increasing fertilization levels. Levels of alkaloids, N-nitrosonornicotine (NNN), and other tobacco-specific nitrosamines (TSNA) were consistently higher in the Burley tobacco than in the bright tobacco, regardless of curing method. In comparing the effects of curing, it was found that NNN and total TSNA levels were higher in the midrib than in the lamina of the air-cured samples, while just the opposite was found for the flue-cured samples. Flue-curing bright tobacco produced three times the level of TSNA vs air-curing the same tobacco. On the other hand, flue-curing Burley tobacco reduced the alkaloids, but greatly increased the TSNA in the lamina. As midribs from the air-cured Burley leaves had three times the TSNA concentration of the lamina, the use of air-cured midribs in tobacco products should be avoided. It was concluded that lower fertilization levels and careful manipulations of curing parameters could lower nitrosamine levels in cured tobacco.
A Preliminary Study on the Fermentation Anomalies of Dark-Fired Tobacco Previously Stored in a Modified Atmosphere at High Absolute Humidity
Authors: Ricciardi M , Aureli G , Dattilo BS 
Published: July 2016

Abstract
In the course of industrial fermentation of dark-fired cigar filler leaf tobacco which was previously stored in a modified atmosphere (air and carbon dioxide), some anomalies, such as a slow temperature increase, mould development, unpleasant odours, little or no ammonia production, were observed. For the investigation of these phenomena a laboratory fermentation system was developed. This model system made it possible to change the values of the main parameters influencing the course of fermentation, to take samples for microbiological and chemical analyses, and to carry out some qualitative evaluations. Fermentations of tobacco stored in modified atmosphere and artificially inoculated with bacteria (Gen. Bacillus) were carried out.
Determination of 25 Low Molecular Weight Carbohydrates in Tobacco by High Performance Ion Chromatography
Authors: Ramusino MC , Dattilo BS , Lucibello A , Rossi SG 
Published: July 2016

Abstract
A High Performance Ion Chromatographic method for the qualitative and quantitative determination of low molecular weight carbohydrates in tobacco leaf is described. The carbohydrates were separated by running isocratic or gradient elutions on columns packed with amino-modified polystyrene divinylbenzene phases, using 0.1 N NaOH as eluent. The compounds were detected by a Pulsed Amperometric Detector, after post-column addition of 1 N NaOH solution. Twenty-two and twenty-four carbohydrates out of twenty-five were separated by isocratic and gradient elution, respectively. Some mono and disaccharides were identified in tobacco samples by their retention times and some quantitative determinations of glucose, fructose, inositol and saccharose were carried out using different varieties of tobacco.
Specific Structural Analysis of Solanesol and Related Compounds by Fast Atom Bombardment in Combination with Tandem Mass Spectrometry
Authors: Jensen NJ , Sumpter T 
Published: July 2016

Abstract
Rapid identification of solanesol even in the presence of a complex matrix can be accomplished using fast atom bombardment (FAB) mass spectrometry in combination with tandem mass spectrometry methods. FAB MS analysis using a nitrobenzyl alcohol matrix doped with lithium yields an abundant (M + Li)+ ion of m/z of 637 which is a very characteristic marker for the presence of solanesol and is quite sufficient for screening for the presence of solanesol in many cases. MS/MS analysis of this ion produces a spectrum which yields specific structural information regarding each isoprene unit of the entire structure. Furthermore, these methods are very useful for characterizing unknowns as demonstrated by the characterization of diol, triol and ester impurities in commercially available solanesol. Application of the MS/MS/MS analysis provides insight into the fragmentation mechanism and can be a useful alternative to conventional labeling methods for confirming spectral interpretations.
Intercept-Reactant Method for the Determination of Aromatic Amines in Mainstream Tobacco Smoke
Authors: Grimmer G , Schneider D , Naujack KW , Dettbarn G , Jacob J 
Published: July 2016

Abstract
A method for the determination of aromatic amines in mainstream smoke of mechanically smoked cigarettes has been developed. The fast reaction of aromatic amines with other smoke constituents formed during the combustion process can be significantly reduced by the addition of an excess of p-toluidine to the acidic collecting solution. From this point the p-toluidine as intercept reactant immediately stabilizes the originally formed amines and results in high recovery rates. The method allows the gas chromatographic determination of aniline, o- and m-toluidine, 1- and 2-aminonaphthalene, 2- and 4-aminobiphenyl, 1-, 2- and 4-aminofluorene, 3-aminofluoranthene, 1-aminopyrene and 6-aminochrysene in the mainstream smoke of a single cigarette. d5-Aniline, d7-2-aminonaphthalene, d9-4-aminobiphenyl as well as fluoranthene and chrysene were used as internal standards. By this new method, 21 ng of 2-aminonaphthalene and about 3,6 ng of 4-aminobiphenyl have been detected in the mainstream smoke of a common blend filter cigarette. As expected, these contents were higher in cigarettes manufactured from alkaline tobacco.
The Removal of Stems from Cut Tobacco
Authors: Zielke D , Liebe R 
Published: July 2016

Abstract
The presence of stems in cut tobacco is detrimental to cigarette quality, resulting in problems during production particularly on today's high-speed makers. Incomplete threshing and the use of unthreshed semi-Oriental tobaccos can increase the stem content in the cut tobacco considerably. The percentage of stems present in cut tobacco was investigated by HauniMaschinenbau AG specifically for semi-Oriental tobacco. Their findings show that not all stems present in the strips or lamina after cutting are classified as “objectionable”. However, the percentage of objectionable stems in the cut tobacco is not inconsiderable and depends on the thickness of the stems present. Reducing the objectionable stem contingent in cut tobacco is therefore a crucial concern of many cigarette manufacturers who set great store on ensuring high-quality product. HauniMaschinenbau AG offers a cut tobacco separator which has been specially designed for this purpose and also used as a cooler. A corresponding model is available in the HauniMaschinenbau AG pilot plant in Hamburg for tests using the customers’ own tobacco.
Conference Report: 53rd Tobacco Science Research Conference (TSRC), September 12-15, 1999, in Montreal, Canada
Authors: Paschke T 
Published: July 2016

Abstract
The 53rd Tobacco Science Research Conference (TSRC), held in Montreal on September 12-15, 1999, was attended by about 300 scientists; 82 papers and 11 posters were presented. A keynote theme of the Conference was addressed in the Symposium on “Genetics and the Future of Tobacco”, with four contributions focussing on the effects of modern gene technology on tobacco growing, possible uses of transgenic tobacco and the main areas of research in this field, as well as consumer acceptance of transgenic products and regulatory issues, respectively.
Reaction of Indicator Tobacco Cultivars to Races of Pseudomonas syringaepv. tabaciTox+
Authors: Cole DL , Mapuranga N 
Published: July 2016

Abstract
Three races of Pseudomonas syringaepv. tabaciTox+ (wildfire) (races 0, 1 and 2) and two races of Tox- (angular leaf spot) (races 1 and 2) have been confirmed on tobacco in Zimbabwe (Zim). Very few cultivars with no resistance to Ps. syringaepv. tabaci are grown commercially and race 0 has not been isolated since 1996. Because we no longer have a viable culture of race 0, we obtained an isolate of race 0 from Kentucky (0 KY), USA in January 2000. We included this isolate in race tests on standard indicator cultivars K E1 (susceptible to all races), KM 10 (resistance to race 0 derived from Nicotianalongiflora), WZ (resistance to races 0 and 1 derived from N. rustica) and a hybrid, K 35 (resistance to races 0 and 0 and 1 derived from N. longiflora and N. rustica respectively). Two leaves on 10-week-old seedlings were inoculated with a bacterial suspension (106 colony forming units [cfu] per mL) by spraying selected areas until just watersoaked and incubating the plants at 28 C and 70% RH for 10 d. The reaction to race 0, measured as lesion diameter, was different from that previously obtained with race 0 (Zim). Races 0 and 1 (Zim) are avirulent on WZ but race 0 (KY) was virulent. Further isolates of race 0 were received from Maryland (MD) and Tennessee (TN). The TN isolates overcame resistance derived from N. longiflora and N. rustica, except where both sets of genes were present in the same cultivar. Reactions have been variable with the race 0 (MD) isolate suggesting it is a mixed culture. We conclude that there are at least four races of Ps. syringaepv. tabaciTox+ worldwide and race 0 (KY) should be designated race 3. On all cultivars, race 2 consistently caused the largest lesions.
Biochemical Changes in β-Cryptogein-Elicited Tobacco: A possible Basis of Acquired Resistance
Authors: Edreva A , Blancard D , Delon R , Bonnet P , Ricci P 
Published: July 2016

Abstract
β-Cryptogein, a proteinaceous elicitor from the phytopathogenic fungus Phytophthoracryptogea, is known to induce leaf necrosis in tobacco and non-specific resistance (expressed in the perinecrotic leaf area) against a wide range of tobacco pathogens. To reveal mechanisms underlying the acquired resistance, biochemical changes in leaves of β-cryptogein-elicited tobacco were followed three, five and ten days after elicitation. The activities of peroxidase, β-1,3-glucanase and β-glucosidase, as well as the patterns of acidic pathogenesis-related (PR)-proteins were determined. The protected part (perinecrotic area) and the non-protected part (distant extra-perinecrotic area) of leaves of β-cryptogein-stem treated tobacco (cv. Xanthin.c.) were analyzed. Leaves of water-stem treated tobacco served as controls. It was shown that in the protected leaf part β-cryptogein caused significant metabolic shifts early after elicitation, persisting during the whole period studied. An important increase of peroxidase and β-1,3-glucanase activity was recorded. PR-protein components appeared that were absent in the controls. There were negligible changes in β-glucosidase activity. In the non-protected leaf part late and non-significant changes occurred. Taking into account the antimicrobial, regulatory and structure-modifying properties of the biochemical components studied, it may be admitted that β-cryptogein elicited the development of a hostile environment, i.e. a potential for plant resistance against subsequent pathogen invasion.
Handling and Curing Characteristics of Cut-Strip Tobacco. Part 2: Effect of Yellowing Time and Drying Potential
Authors: Johnson WH , Weeks WW 
Published: July 2016

Abstract
This paper presents Part 2 of a study on comparative handling and curing characteristics of cut-strip vs. whole leaf tobacco. Part 1 considered the effect of leaf size (cut-strip size vs. whole leaf), packing density and mode of leaf orientation on cured leaf chemistry and leaf quality; whereas, the present study considers further the effect of leaf form, two yellowing times and two drying potentials during yellowing. Results showed that leaf chemistry and quality were quite similar for cut-strip (15.2 × 22.9 cm) and whole leaf. Insignificant differences were noted for cured leaf starch and sugars, although slightly lower levels of alkaloids (significant at the 0.01 level) were observed for cut strip. Curing treatments significantly affected leaf chemistry. Increased yellowing time resulted in lower levels of starch and higher levels of sugar. Sugars were also higher for tobacco yellowed under the higher drying potential. The two forms of leaf responded similarly to different curing schedules (i.e. no interaction of leaf form with schedule). Also, government grade and price data were essentially unaffected by leaf form or curing schedule over the range of variables tested. Cured leaf starch was abnormally high on the average for both leaf forms. Interestingly, starch levels were lower when intact tobacco was bulk-cured in racks rather than box cured (6.35% vs. 9.02%). Since curing schedules were similar, air velocity in the two curing methods might be a factor. Also the cured leaf starch content was about 56% lower for tobacco produced at the Oxford Tobacco Research Station (in a secondary study) than at the Central Crops Research Station. It is postulated that carbohydrate and nitrogen metabolism during growth and maturation might be affected by excess rainfall events and/or nitrogen availability, with subsequent effects on starch-to-sugar conversion during curing.
Wild Nicotiana Species as a Source of Cytoplasmic Male Sterility in Nicotianatabacum
Authors: Nikova V , Vladova R 
Published: July 2016

Abstract
The results of our experiments executed to obtain tobacco male sterile lines through interspecific hybridization are summarized. Ten wild species from the genus Nicotiana: N. excelsior (exc), N. amplexicaulis (amp), N. rustica (rus), Nicotianaglauca (gla), N. velutina (vel), N. benthamiana (ben), N. maritima (mar), N. paniculata (pan), N. longiflora (lon) and N. africana (afr) were used as cytoplasmic donors and N. tabacum, cv. HarmanliiskaBasma (HB) as a donor of the nucleus. Genetic effects of cytoplasmic-nuclear interaction of the studied species are discussed. Our results suggested that cytoplasmic male sterility (CMS) was expressed when the cytoplasms of the above mentioned wild Nicotiana species were combined with the nucleus of N. tabacum. The 10 sources of CMS obtained in tobacco were characterized by altered flower phenotypes. Flowers are classified into types according the stamen, pistil and corolla modification. All these CMS sources were backcrossed to Oriental tobaccos, cvs. Tekne, Nevrokop B-12, Kroumovgrad 90 and Djebel 576, to develop corresponding CMS lines. The investigated cytoplasms produced compete male sterility in all those cultivars. The CMS lines preserved flower types, specific for every “sterile” cytoplasm. The extent of male organ modifications varied from apparently normal (but pollenless) stamens in CMS (pan), (afr), some plants of (vel) (mar) through different degrees of malformations (shriveled anther on shortened filaments (lon), pinnate-like anthers on filaments of normal length (amp), petal - (ben), pistil- or stigma-like structures (rus), (gla)) to lack of male reproductive organs in (exc) and in some plants of (vel), (mar), (rus) and (gla). Most of the above mentioned cytoplasms had normal female gametophyte and good seed productivity. Alterations of the pistils were observed in CMS (rus), (exc) and (ben) causing reduction of the seed set. Electrophoresis of seed proteins of the tobacco cultivars and their CMS lines also suggested that the nuclei of wild species was entirely displaced by the nucleus of N. tabacum. CMS lines with cytoplasms of N. velutina, N. maritima, N. paniculata, N. longiflora and N. amplexicaulis were selected as suitable for seed production in tobacco.
Editorial
Authors: Heller WD , Scherer G 
Published: July 2016

Abstract
In this issue of BeitraegezurTabakforschung International/Contributions to Tobacco Research, we publish a ‘Letter to the Editor’ written by R. Baker (p. 360). This letter is a reply to a commentary by S. Shatenstein published in Tobacco Control (11, 174-175, 2002) which provided a critique of a review written by Baker on standards for smoking-machine methodology which appeared in this journal (Beitr. Tabakforsch. Int. 20, 23-41, 2002). The reason why we as editors of Beitraege have decided to publish the letter is simple, the editors of Tobacco Control, the appropriate place for publication, did not allow its publication. In the interest of a fair and scientific discussion of this matter, we think that an author whose paper is criticized publicly should have the chance to reply. However, we regret that Shatenstein's critique and Baker's reply might reach totally different readers.
Potassium Organic Salts as Burn Additives in Cigarettes
Authors: Liu C , Parry A 
Published: July 2016

Abstract
Three potassium salts of organic acids, namely malate, citrate and tartrate, have been sprayed onto flue-cured blend tobacco and subsequently tested for their performance as burn additives in cigarettes. In one experiment where potassium malate was added to vary the final tobacco potassium from ca. 3.1% to 8.3% (wet weight), an almost linearly reduction in puff temperature was measured. This was accompanied by a gradual increase in the cigarette's pressure drop. In another set of experiments where the final tobacco potassium contents were increased to ca. 5.1%, the three potassium salts showed almost equal reduction in the mainstream nicotine-free-dry-particulate-matter (NFDPM) at 32-35%, nicotine at 25-32% and carbon monoxide at 24-35%. Puff number showed ca. 23% increase with malate, 13% with citrate and almost unchanged for tartrate. Evidence of melting and coating by potassium malate was discovered in cigarette ash by scanning electron microscopy (SEM). This contributed to a noticeable change in ash morphology: small ash particles appeared to be coated and more tightly bonded together by the melt. This phenomenon was thought to be able to restrict the airflow during puffing, hence causing the measured increase in pressure drop, and the reductions in puff temperature, NFDPM, nicotine and carbon monoxide.