bluuebunny/crossref_metadata_2025 huggingface dataset:
The Roles of Amino Acids and Sugars in the Production of Volatile Materials in Microwave Heated Tobacco Dust Suspensions
Authors: Coleman WM , Perfetti TA
Published: July 2016

For the first time, the role(s) of selected amino acids and sugars in the production of volatile compounds in microwave prepared heat treated tobacco suspensions (HTTS) has been unambiguously defined. The role can be expressed in two major reaction pathways:

1) Strecker degradation of amino acids and 2) amino acid/sugar Maillard-type reactions. The mechanism of the Strecker degradation was confirmed by the addition of selected 13C- labelled amino acids to the reaction suspension. The addition of the amino acid resulted in a dramatic increase in the concentration of the specific, appropriate, low molecular weight Strecker aldehyde in the headspace above the reaction suspension. The mechanism of the amino acid/sugar Maillard-type reactions was substantiated by: 1) adding a wide array of amino acids to the suspension;

2) by employing 15N-labelled amino acids; and

3) employing 13C-labelled sugars. Addition of amino acids to the suspension followed by heat treatment resulted in significant increases (2 ×) in the concentration of volatile pyrazines relative to the control. Most amino acids significantly increased the concentration of headspace pyrazines. Reactivity differences, as a function of sugars, was also demonstrated. Analysis of the headspace above suspensions incorporating 15N-labelled amino acids and 13C-labelled sugars revealed the 15N and 13C atoms to have been distributed throughout a wide array of volatile pyrazines. The distribution of the 15N atoms within the pyrazines was unique to the amino acid and the distribution of the 13C atoms was linked to the type of sugar employed. These results have documented for the first time in a heat treated tobacco formulation the mechanisms of amino acids and sugars in the production of volatile compounds which have documented intense sensory characteristics.
Variability of Peronospora Tabacina A. - An Isoenzyme Study
Authors: Edreva A , Delon R , Coussirat JC
Published: July 2016

The variability of P. tabacina A. populations was studied by using the isoenzymes of peroxidase (PO), malate dehydrogenase (MDH) and superoxide dismutase (SOD) as molecular markers. P. tabacina conidia/conidiophores from N. tabacum crops cultivated in distant areas of Europe (France and Bulgaria) were investigated during a long period of time (1978-1992). It was found that no variations of P. tabacina as a function of space and time occurred. The data point to the genetical stability of the presently spread strain of the pathogen and the lack of processes of new strain formation. However, a significant variability of P. tabacina as a function of host plant was established. Suspension of conidia/conidiophores of P. tabacina originating from N. tabacum (P 48 cv.) was used to inoculate the wild species N. repanda. First conidia/conidiophores of P. tabacina produced on the new host plant (designated as Pt/Nr) as well as those from the “classical” host, N. tabacum (designated as Pt/Nt) were analysed. Thus, two types of P. tabacina (according to their origin) were compared. It was shown that one MDH and most PO isoenzymes present in Pt/Nt were not observed in Pt/Nr; these isoenzymes repressed following the transfer were common for Pt/Nt and its N. tabacum host. Moreover, in conidia/conidiophores of Pt/Nr new isoenzymes appeared, namely one major PO, one MDH and a block of three SOD isoenzyme components. These isoenzymes were common for Pt/Nr and the new host, N. repanda. It is noteworthy that all fungus specific isoenzymes present in Pt/Nt (one PO, five MDH and seven SOD components) were conserved in Pt/Nr. The results reveal molecular mechanisms underlying relationships between host plants and obligatory fungal pathogens, such as P. tabacina. They could be used in blue mold epidemiology research.
Chiral-Gas Chromatography-Selected Ion Monitoring-Mass Selective Detection Analysis of Tobacco Materials and Tobacco Smoke
Authors: Perfetti TA , Coleman WM
Published: July 2016

A novel method for the detection, separation, and quantification of the optical isomers of nicotine has been developed. The method has been applied to analyse extracts of tobacco seeds, processed tobacco suspensions, reconstituted tobacco sheet materials, individual tobacco varieties, blends of tobaccos, and cigarette smoke condensate. The methodology does not involve any further sample preparation other than that which is normally used to analyse tobacco alkaloids by the modified method of Gordon et al. (73), or the standard FTC smoke analysis routinely performed by most tobacco and smoke analysis laboratories. Near baseline resolution was obtained for enantiomers, yielding a lower detection limit of approximately 2 % d-nicotine in a mixture of d-and l-nicotine. There was essentially no d-nicotine found in any of the tobacco samples. Detectable levels of d-nicotine were found in most of the samples of cigarette smoke condensate when the cigarettes were smoke by the FTC method. The presence of Oriental tobacco in the cigarette appeared to be related to whether d-nicotine was generated in the mainstream cigarette smoke condensate. When the same cigarettes were smoked under a more stressful puffing regime the level of d-nicotine in the smoke did not increase and in some cases the level of d-nicotine decreased. This work supports prior literature that detected and quantified the presence of d-nicotine in cigarette smoke condensate.
Chiral-Gas Chromatograpy-Selected Ion Monitoring-Mass Selective Detection Analysis of Secondary Alkaloids in Tobacco and Tobacco Smoke
Authors: Perfetti TA , Coleman WM
Published: July 2016

Chiral gas chromatography-mass selective detection has been successfully employed in the analysis of secondary alkaloids in selected tobacco materials and cigarette smoke condensate. No extensive sample preparation is involved. A lower detection limit of ~2 % d-nornicotine, d-anabasine and d-anatabine in a mixture of l and d-isomers was achieved. The levels and the enantiomeric ratios of nicotine, nornicotine, anabasine and anatabine varied in different tobacco types. The enantiomeric ratios of nicotine, anabasine and anatabine in mainstream cigarette condensate also varied but were generally representative of the enantiomeric ratios for the alkaloids found in the leaf. The enantiomeric ratio for nornicotine in mainstream cigarette condensate also varied and was not representative of the enantiomeric ratios for the alkaloids found in the leaf. Preferential decomposition or racemization may account for the differences seen in the yields of isomers of nornicotine transferred to the mainstream smoke condensate. An experiment was conducted to determine if the d-nornicotine present in tobacco contributed to the yield of d-nicotine in mainstream smoke condensate. The results of that experiment indicated that the yield of d-nicotine transferred to mainstream smoke did not change significantly when either large levels of endogenous nornicotine were present in the leaf or when large levels of exogenous levels of d-, l-nornicotine were applied to the tobacco rod prior to smoking. The limiting factor in the production of d-nicotine in mainstream cigarette smoke condensate may be the concentration of methyl radicals present to react. Further work must be conducted to unravel the mechanism involved in the production of d-nicotine in cigarette smoke condensate.
Evaluation of the Efficacy of CGA 245704 Combined or Not with CGA 329 351 (Mefenoxam) for the Control of Tobacco Blue Mold (Peronospora Tabacina): Results of Four Years of Experiments
Authors: Delon R , Cailleteau B , Verrier JL , Tanne MN , Sylvestre M
Published: July 2016

A compound for activating systemic resistance (CGA 245 704), in the chemical class of benzothiadiazoles, was studied since 1993 for the control of tobacco blue mold (Peronosporatabacina A.) in seedbeds and in the field. One foliar application of CGA 245 704 at 1.6 g active ingredient/hl every 14 days protected tobacco plants against blue mold but protection was not total. Mixed with mefenoxam (CGA 329 351) at 16 g active ingredient/hl the protection is equivalent to standard Acylon¯ TC (25 % metalaxyl, 50 % maneb) applied as foliar spray at 0.160 kg/hl (40 g active ingredient metalaxyl per hl). This allows a reduction in the quantity of fungicides dispersed in the environment and the pesticide residues on the tobacco leaves. At the rate applied, no phytotoxic effects were observed in seedbeds or in the field.
The Incidence and Consequences of Filter Vent Blocking Amongst British Smokers
Authors: Baker RR , Dixon M , Hill CA
Published: July 2016

Vent blocking, the intentional or unintentional covering of the filter ventilation holes during smoking, is an aspect of smoking behaviour which could influence mainstream smoke yields. This study was designed to determine if, and to what extent, vent blocking by smokers’ lips occurs. Three groups of British smokers were asked to smoke their own brand of cigarette which was either an unventilated filter brand, or one of two brands containing different levels of filter ventilation. 300 Smokers were used in each group and the filter butts were collected. Approximately 10 filter butts per smoker were collected. The filter tipping papers were removed and treated with a ninhydrin solution. This stained the saliva imprint on the paper so that the mouth insertion depth of the cigarette could be measured. In addition, levels of retained nicotine on the filters were also determined. This, together with the known filtration efficiencies of the filter, enabled an estimate to be made of the mainstream nicotine yield of the cigarette during the smoking. The results indicate that British smokers have an average insertion depth of about 8.5 mm. 85 % of the ventilated filters examined showed no vent coverage by the smokers’ lips, 15 % showed some coverage. Based on the techniques used in the present study it appears that the presence or absence of filter ventilation zone coverage by lips is not reflected in the estimated nicotine yields to smokers. It is likely that other smoker behaviour factors have a more substantial role in determining nicotine yields within each cigarette delivery category.
Internal Standard-based Analytical Method for Tobacco Smoke Vapor Phase Components
Authors: Omori F , Higashi N , Chida M , Sone Y , Suhara S
Published: July 2016

We developed an internal standard-based method to analyze the vapor phase components of mainstream smoke. This method collects vapor phase components from sample cigarettes, which are smoked by a linear automatic smoking machine in a sampling bag. An internal standard gas was introduced to the bag. A 6-port valve with a 2-ml sampling loop was placed between the vapor phase smoke outlet of the smoking machine and the bag to regulate the volume of the internal standard. The mixed gas sample was then introduced, by an automatic injection device developed in-house, to a gas chromatograph (GC) for ten successive analyses. The sample in the bag was analyzed every two hours to assess the time serial changes of vapor phase smoke components as well as of the internal standard. After 18 hours, in the tenth analysis, the amounts of 37 vapor phase components decreased by less than 5 % from those in the first analysis. The repeatability of the sample analysis was assessed and 45 vapor phase components had coefficients of variation of less than 5 %. The overall reproducibility of this method including tobacco samples and instruments was also assessed using five other sampling bags and achieved coefficients of variation of less than 6 % for 42 vapor phase components. The advantages of this method include capability to handle 10 tobacco samples in a serial manner, capability to collect both the vapor phase and semivolatile components, and precise, easy and continuous component analyses. We also present the results of multivariate analyses for the vapor phase and semivolatile components from 59 sample cigarettes.
Sampling and Analysis Techniques for Odorous Volatile Organic Compounds (VOCs) from Concentrated Aged Sidestream Smoke (SSS)
Authors: Taylor HJ , Winter DB , Miranda EJF , Pereira da Silva JR
Published: July 2016

This work is part of a long term study aimed at determining the odorous Volatile Organic Compounds (VOCs) in Environmental Tobacco Smoke (ETS) deposited on clothing. In this preliminary phase of the study sidestream smoke (SSS) rather than true ETS was used, for the following reasons. Firstly, the sampling system had to be modified in order to increase the concentration of odorous VOCs collected so that the later analytical stages could proceed. This meant that the sampling system was developed to collect concentrated SSS on cloth. Secondly, the cigarette butts were removed from the system so that they did not contribute to the odour; and thirdly the cloth was left to age for 48 hours. Therefore, technically, the study was the determination of the odorous VOCs in aged concentrated SSS deposited on cloth; this will be referred to as ‘aged SSS’ from this point onwards throughout this paper. This paper describes the method development of sampling and analysis techniques for odorous VOCs in aged SSS deposited on cloth. In addition, this paper demonstrates the processes of heartcutting and the mass spectral identification of odorous components using a concentrated tobacco steam distillate extract. A sampling chamber was constructed to allow the aged SSS to be deposited on the surface of the fabric, and to ensure that the amount of smoke deposited on the cloth was sufficiently high to conduct further analyses. The fabric was then desorbed via a purpose built purge- and-trap system to release the volatiles onto selected adsorbents. Each adsorbent in turn was solvent desorbed and a concentrated extract obtained. The aged SSS extracts were then directly injected into a multidimensional Gas Chromatography/Mass Spectrometry (GC/MS), and GC profiles obtained. These chromatographic profiles facilitate both the direct comparison of the range of VOCs trapped and desorbed from each adsorbent, and the identification of odorous regions when used in conjunction with the odour port. The aged SSS chromatograms presented in this paper only show the range of VOCs collected by the different adsorbents. Further experiments were also conducted with a concentrated tobacco steam distillate extract. These results were obtained by directly injecting the extract into the multidimensional GC/MS system, connected to an odour port. Volunteers were then asked to sensorially evaluate the odour of the extract and to identify any odorous notes during the analysis. Two concentrated tobacco steam distillate extract chromatograms are presented.
The Thermodynamics of Tobacco-Water Interactions
Authors: Banyasz JL
Published: July 2016

An equation to describe the water sorption isotherm of tobacco is developed based on a model of the tobacco-water system as a mixture or solid solution comprised of water and water binding sites of many different kinds. It is assumed that free water has an activity coefficient of one. The result is an equation that predicts moisture content as a function of relative humidity given the numbers of each of the different kinds of sites and the associated water binding equilibrium constants. It is shown that this multi-site equation reduces to a one site equation if the different kinds of water binding sites are symmetrically distributed with regard to their affinity for water. The result is a two parameter, average site equation that fits water sorption data for tobacco over the range of 10-80% relative humidity. The average site equation is identical to the equation derived by BRUNAUER, EMMETT and TELLER for binding to surface sites (1). The two models start from very different points of view but come to the same conclusion because they are ultimately based on thermodynamics which is indifferent as to the physical nature of the sites. Inferences as to the microscopic nature of water binding sites cannot be made from thermodynamic isotherm equations. In order to describe the effects of water on the physical properties of tobacco the solution analogy is extended further. If tobacco is a mixture or solution of unhydrated sites, hydrated sites and free water, then the value of a physical property should be a function of the concentrations of those species and the associated partial molar values of the property. As the total moisture content changes the distribution of species will change and, in turn, change the properties. Applications of this rationale are presented for heat capacity, thermal diffusivity and the kinetics of the Browning reaction. The results demonstrate that the parameters derived from water sorption data play a more general role in the thermodynamics of the tobacco-water system.
The Quality Estimation of Different Tobacco Types Examined by Headspace Vapor Analysis
Authors: Hasebe H , Suhara S
Published: July 2016

In order to judge the quality of tobacco leaf, it is necessary to conduct sensory smoke evaluations. However, these are subjective and the results are difficult to quantify. Therefore, we have attempted to establish a quantitative method for evaluating tobacco quality by comparing results of headspace analysis. Forty-seven leaf samples of different types (flue-cured, Burley, Oriental) were analyzed. The first step in this study was to have a panel of experts smoke cigarettes made from the test tobaccos and have them evaluate 10 sensory attributes. The scores were then analyzed by the technique of principal component analysis (PCA). Results showed that the score for the flavor note attribute indicated the type of tobacco and the scores of the other 9 attributes were combined as a total to indicate smoking quality. Following the sensory study, headspace vapors of the test tobaccos were analyzed with a headspace sampler, gas chromatography, mass spectroscopy system (HS-GC-MS), in which the gas sampling loop and the HS-GC transfer line were deactivated. In order to obtain conditions for good reproducibility, the heating temperature and time of the headspace vials were examined. PCA was performed for the headspace vapor (HSV) analysis results for 31 selected peaks. The first and second principal components could be used to classify tobacco types. The third principal component partially indicated differences of smoking qualities. Finally, multiple regression analysis was performed on the HSV analysis results in order to estimate the smoking quality scores. The regression model of all samples combined had a low regression coefficient. Then, we separated the results of the three tobacco types, as we considered that the headspace data might reveal information about the classifications themselves. The final outcome was a regression model that could be applied to each type with a higher accuracy. The variables that entered the models were compared.
Methods for Confirming the Gram Reaction of Gram-variable Bacillus Species Isolated from Tobacco
Authors: Morin A , Poirier N , Vallee S , Porter A
Published: July 2016

Bacillus is a predominant genus of bacteria isolated from tobacco. The Gram stain is the most commonly used and most important of all diagnostic staining techniques in microbiology. In order to help confirm the Gram positivity of Bacillus isolates from tobacco, three methods using the chemical differences of the cell wall and membrane of Gram-positive and Gram-negative bacteria were investigated: the KOH (potassium hydroxide), the LANA (L-alanine-4-nitroanilide), and the vancomycin susceptibility tests. When colonies of Gram-negative bacteria are treated with 3% KOH solution, a slimy suspension is produced, probably due to destruction of the cell wall and liberation of deoxyribonucleic acid (DNA). Gram-positive cell walls resist KOH treatment. The LANA test reveals the presence of a cell wall aminopeptidase that hydrolyzes the L-alanine-4-nitroanilide in Gram-negative bacteria. This enzyme is absent in Gram-positive bacteria. Vancomycin is a glycopeptide antibiotic inhibiting the cell wall peptido-glycan synthesis of Gram-positive microorganisms. Absence of lysis with KOH, absence of hydrolysis of LANA, and susceptibility to vancomycin were used with the Gram reaction to confirm the Gram positivity of various Bacillus species isolated from tobacco. B. laevolacticus excepted, all Bacillus species tested showed negative reactions to KOH and LANA tests, and all species were susceptible to vancomycin (5 and 30 µg).
Mini-Review: On the Transfer of Nicotine from Tobacco to the Smoker. A Brief Review of Ammonia and “pH” Factors
Authors: Dixon M , Lambing K , Seeman JI
Published: July 2016

A brief review is presented of the scientific literature on the effects of ammonia compounds, when used as tobacco additives, on the smoke chemistry and bioavailablity of nicotine. The review concludes that ammonia compounds used in the manufacture of certain types of tobacco sheet materials:

1) contribute to the flavor properties of cigarette smoke,

2) do not increase the amount, rate or efficiency of nicotine transferred from tobacco to mainstream smoke (MS),

3) do not increase the percentage of nicotine in MS gas phase using the FTC/ISO (Federal Trade Commission/International Organization for Standardization) method,

4) have no influence on the determination of MS nicotine yield as measured by the FTC/ISO method, and

5) do not increase the total rate or amount of nicotine absorbed by the smoker.

The review also examines the use of pH as it relates to tobacco and to smoke and suggests a terminology which more accurately describes the measurement (pH of aqueous extract of tobacco, pH of aqueous extract of smoke, and pH/electrode in smoke). Lastly, a number of research gaps in these areas are identified.
“Smoke pH”: A Review
Authors: Rodgman A
Published: July 2016

The analytical methods developed since the 1950s to determine the “smoke pH” of cigarette mainstream smoke (MSS) are reviewed. Most of the methods involve averaging the values obtained with all the puffs from a cigarette or averaging values from the total number of puffs from several cigarettes plus solution of the MSS in various quantities of water prior to pH determination. “Smoke pH” values thus obtained have little relevance to the situation involving a smoker who smokes a cigarette one puff at a time. In the human biological situation, the smoke components must traverse a layer of buffered fluid separating the smoke-filled respiratory tract cavity and the underlying tissue. Seldom is the effect of either the volume or the pH of the buffered fluid taken into account in determining the “smoke pH” of cigarette MSS taken one puff at a time. While numerous recent discussions have dealt with the effect of pH on the nature (degree of protonation) of nicotine in cigarette MSS and its rate of absorption by the smoker, seldom is the volume and/or pH of oral cavity saliva or of the fluid coating the lung surface considered in the assessment of either the nature or absorption of nicotine by the smoker. If the degree of protonation of nicotine be pH dependent, then the degree of protonation of nicotine as it traverses the film of fluid separating the respiratory tract cavity and the underlying tissue must be dependent on the pH of the buffered fluid and not on the “smoke pH” per se. Statements that adjustment of the “smoke pH” by ammoniation of one or more tobacco blend components increases both the level of MSS nicotine and its rate of absorption, thus resulting in greater consumer acceptance and continuation of smoking, fail to take into account the other changes that occur in the MSS composition to enhance its consumer acceptability. Inclusion of modest percentages of ammoniated tobacco in the blend increases the “smoke pH” of the MSS but does not necessarily increase MSS nicotine level. Not only are the MSS levels of several low molecular acids, aldehydes, and ketones known to be respiratory tract irritants substantially reduced but also the MSS levels of several highly flavorful pyrazines are substantially increased. These MSS composition changes yield an MSS classified as milder and more flavorful and whose consumer acceptability is considerably enhanced. Until the pH of MSS is determined on a per puff basis in a system simulating that in the oral cavity or the lung of the smoker, the nature of specific smoke components at the time of contact and their reactivity with respiratory tract tissue remain highly speculative. “Smoke pH” value for MSS, like the “tar” value for MSS, provides little, if any, useful information about the chemical composition of the source of the MSS or about its chemical and biological properties.
The Transfer of Nicotine from Nicotine Salts to Mainstream Smoke
Authors: Perfetti TA , Norman AB , Gordon BM , Coleman III WM , Morgan WT , Dull GM , Miller CW
Published: July 2016

Transfer of nicotine to mainstream smoke was measured for Reference cigarettes made with the addition of 20 -40 mg of seven different nicotine salts, d- and l-nicotine and N’-formylnornicotine. Regression analysis of the nicotine yields from these cigarettes as a function of the nicotine content of the tobacco rods indicated an average nicotine transfer efficiency (17.5%), similar to that found for a separate series of cigarettes made with single-grade tobacco materials (16.2%). Analysis of the enantiomeric purity of the smoke nicotine from the cigarettes made with added nicotine salts and neat nicotine showed no evidence of conversion between l- and d-nicotine during the smoking process. The cigarette made with added N’-formylnornicotine showed no evidence of additional nicotine transfer attributable to reduction of this compound to nicotine. A third series of cigarettes were made with varying levels of d- and l-nicotine added to a tobacco blend and to reconstituted tobacco to further investigate transfer efficiency of the enantiomers. Regression analysis indicated no statistically significant difference between transfer efficiencies of d- and l-nicotine. These results suggest that nicotine salts and d- and l-nicotine transfer to smoke at the same efficiency. However, transfer efficiency of either compound was lower when applied to reconstituted tobacco (9.7%) than when applied to the Reference tobacco blend (15.3%). The thermal stabilities of nicotine salts have little bearing on efficiency of transfer to smoke or on racemization between d- and l-nicotine. Formation of d-nicotine in mainstream smoke via reduction of N’-formylnornicotine does not appear to occur.
Aflatoxin B1 and Tobacco Products
Authors: Massey ED
Published: July 2016

The potential for aflatoxin B1 contamination of tobaccos and its subsequent transfer to smoke has been raised. This paper examines published work relevant to this issue and concludes that aflatoxin B1 is not a contamination issue on tobaccos and, even if present, would decompose in the burning cigarette and would not transfer to smoke.
Determination of Nicotine in Tobacco: Collaborative Study
Authors: Franke JE , Bennett CB , Davis RE , Thomsen HV , Johnston KS
Published: July 2016

An international collaborative study was performed to compare several analytical methods for the determination of nicotine in tobacco that are in current use around the world. Five nicotine methods were evaluated and compared, specifically methyl-t-butyl ether (MTBE) extraction with capillary-column gas chromatography (GC), n-hexane extraction with capillary-column GC, n-hexane extraction with packed-column GC, methanol/ammonia extraction with capillary-column GC, and aqueous extraction with continuous flow analyzer (CFA) colorimetry. A total of 37 laboratories participated in the study, with between 9 and 18 laboratories submitting data per nicotine method. Repeatability, reproducibility, and mean nicotine statistics were calculated and compared for each method. Results for reproducibility (%) and mean nicotine difference (%, relative to the mean of the three capillary-GC methods), respectively, for each method are as follows: MTBE method (2.5%, -1.40%), hexane-capillary (4.5%, +0.06%), methanol/ammonia (3.7%, +1.34%), CFA (4.4%, +4.08%), and hexane-packed (5.8%, +4.14%). Pair-wise group comparison tests with simultaneous 95% confidence intervals were used to compare the sample nicotine values between any two given methods. Eight of the ten pair-wise comparisons were statistically different at 95% confidence, the two statistically indistinguishable pair-wise comparisons being CFA vs. hexane-packed and hexane-capillary vs. methanol/ammonia. The results of this collaborative study will be useful toward the goal of standardizing on a reference method for nicotine analysis in tobacco and tobacco products.
Determination of Mercury in Mainstream Cigarette Smoke by Conventional and Amalgamation Cold Vapor Atomic Absorption Spectrometry
Authors: McDaniel RL , Torrence KM , Self DA , Chang MJ
Published: July 2016

A method for differentiation of gas- and particulate-phase mercury in mainstream cigarette smoke was developed using electrostatic precipitation (EP) as the trap for the particulate phase and impingers containing acidic potassium permanganate solution as the trap for the gas-phase portion. The mercury collected from the gas phase was analyzed by conventional cold vapor atomic absorption spectrometry (CVAAS) and the particulate phase was analyzed by gold amalgamation CVAAS. Cigarettes were smoked under two smoking regimes, FTC (35-mL puff volume, 2 s puff duration and one puff every 60 s) and an alternative (45-mL puff volume, 2 s puff duration, one puff every 30 s and 50% of any ventilation holes blocked) currently recommended by the Massachusetts Department of Health. For the 1R4F reference cigarette smoked under the FTC smoking regime, the mercury found in the particulate phase was less than 0.2 ng/cig, compared with 4.9 ng/cig in the gas phase. By changing smoking parameters, the mercury concentration in mainstream smoke was found to change proportional to the delivery of cigarette smoke condensate (CSC) for the same type of cigarette. However, the mercury level for different types of cigarettes smoked under the same smoking parameters had no linear relationship with CSC delivery. Spiked recovery was 98% AA± 8% for gas-phase mercury and 97% AA± 2% for the particulate phase. These results indicate that the analytical method developed is suitable for the determination of mercury in mainstream smoke. For routine analytical work in a smoking laboratory, only the gas phase needs to be analyzed for determination of mercury in mainstream smoke because the amount of mercury in the particulate phase is negligible.
Propagation of Cigarette Static Burn
Authors: Miura K , Kitao S , Egashira Y , Nishiyama N , Ueyama K
Published: July 2016

A propagation model of cigarette static burn at the cigarette periphery is proposed. Propagation of cigarette static burn is characterized by intermittent burn of the cigarette paper. The burning rate depends on the period of flash burn of the paper and is independent of the burning width. By measuring the local temperature near the front line of the burning propagation, the rate-determining step was identified as the time required to ignite the paper. A mathematical analysis was performed by calculating the heat transfer at the periphery during the paper heating period, and it was revealed that the thermal properties of the cigarette are the dominant factors of cigarette static burn. Modeling results showed good agreement with measured data.
Floral Morphology and Some Other Characteristics of Iso-genomic Alloplasmics of Nicotianatabacum L.
Authors: Berbec A
Published: July 2016

Cytoplasms of several Nicotiana species - N. amplexicaulis, N. bigelovii, N. debneyi, N. eastii, N. exigua, N. glauca, N. glutinosa, N. goodspeedii, N. knightiana, N. occidentalis, N. plumbaginifolia, N. raimondii, N. suaveolens, N. undulata - were bred into the N. tabacum genomic background of flue cured tobacco cv. Zamojska 4. The collection includes also a cytoplasmic male sterile (cms) analogue of cv. Zamojska 4 with mutated cytoplasm of N. tabacum. Some of the alloplasmics were originally obtained in this laboratory (N. amplexicaulis, N. eastii, N. exigua, N. glauca, N. knightiana, N. raimondii). The remaining ones were acquired from other laboratories and backcrossed into Zamojska 4. All alien cytoplasms except that of N. knightiana produced full male sterility in Zamojska 4. The extent of male organ modifications varied from complete absence of stamens (N. suaveolens, N. tabacum) to petaloid and stigmatoid structures (most common effect) to malformed stamens (N. amplexicaulis, N. glauca) to apparently normal stamens (N. raimondii, N. knightiana). The majority of the alloplasmics showed response to tentoxin that was compatible with the cytoplasm donor. The exceptions were those involving N. exigua, N. raimondii, (N. raimondii I), and the cytoplasmic mutant of N. tabacum. There was some variation in growth and morphology among the alloplasmic variants of Zamojska 4. Under field infestation alloplasmics with the cytoplasm of N. plumbaginifoliaand N. eastiishowed symptoms of blue mold whereas the remaining alloplasmics and cv. Zamojska 4 were highly tolerant of that disease.
Comparative Study of Leaf Surface Texture and Ability to Expand of Cured Tobacco
Authors: Rohr R , Eberhard A , Delon R , Descombes JP , Demor JM
Published: July 2016

Tobacco leaf texture, appreciated by the difference of surface roughness of cured leaves, is studies with light microscopy and scanning electron microscopy (SEM). The leaf texture is obviously determined by the presence or absence of conical cellular protuberances on the adaxial side of the leaf. Considering the anatomic point of view, the leaf thickness, always more important when the leaf texture is open, is the only objective criterion which could be associated to the texture. The ultra-structural study with SEM and transmission electron microscopy (TEM) demonstrates that the expansion capacity of tobacco doesn't rely on cytological factors such as cellular reserves or debris. The expansion capacity could be inversely proportional with the relative importance of the mesophyll comparing to palisade parenchyma. On the studied material, no direct relation between the leaf texture and the expansion capacity has been noticed.
Puff-by-puff Mainstream Smoke Analysis by Multiplex Gas Chromatography-Mass Spectrometry
Authors: Thomas CE , Koller KB
Published: July 2016

A puff-by-puff mainstream smoke procedure has been developed that provides the sensitivity and selectivity of a gas chromatography-mass spectrometry (GC-MS) system. The smoke analysis is based on automated sample collection and injection into the GC system. This development builds on, and complements, prior puff-by-puff procedures developed by Philip Morris USA, that utilized infrared (IR) analysis of gas-phase mainstream smoke. IR analysis of the gas-phase smoke for individual smoke constituents relies on the unique spectroscopic absorption patterns of each analyte. The new multiplex procedure relies on both chromatographic separation as well as spectroscopic separation. A significant feature of this method is that multiple injections are made prior to the complete elution of the first injected sample. The benefits of this methodology are that both sensitivity and the number of detected compounds are enhanced. While the multiplex method increases the complexity of the chromatographic data, the mass spectral analysis provides a means for data reduction to meaningful results. Many smoke constituents that are at concentrations below the Fourier transform infrared (FTIR) detection limit are observable with the multiplex analysis while maintaining the feature of puff-by-puff characterization of fresh smoke. The gas-phase mainstream smoke filtration performance of standard adsorption materials are discussed as a demonstration of the versatility and information content of this analytical procedure.
Studies of Polycyclic Aromatic Hydrocarbons in Cigarette Mainstream Smoke: Identification, Tobacco Precursors, Control of Levels: A Review
Authors: Rodgman A
Published: July 2016

During the period of tobacco smoke research from the early 1950s to the mid-1960s it was repeatedly asserted that a) tobacco and many tobacco components were involved in the pyrogenesis of polycyclic aromatic hydrocarbons (PAHs), several of which were reported to initiate tumors on the skin of laboratory animals and b) tobacco additives (flavorants, casing materials, humectants) were highly likely to be similarly involved in PAH pyrogenesis. Extensive knowledge on PAHs was deemed highly necessary because of their claimed importance in the smoking-health issue. The numerous assertions about the generation of PAHs in cigarette mainstream smoke (MSS) triggered extensive and intensive research both within and outside the Tobacco Industry to define the nature of the PAHs, their per cigarette MSS delivery amounts, their precursors, etc. It was not until 1960 that VAN DUUREN et al. (1) reported three specific aza-arenes in cigarette MSS that were asserted to be involved in smokers’ respiratory tract cancer. As noted in a recent Letter to the Editors (2), the presence of these three aza-arenes in tobacco smoke has never been confirmed. Between 1960 and 1965, other MSS components (phenols as promoters, polonium-210, N-nitrosamines, ciliastatic compounds) were asserted to be responsible for smoking related diseases. However, no major assertions were made that phenols, polonium-210, or the N-nitrosamines were derived from flavorants, casing materials, or humectants. Some investigators did report that several ciliastats were derived from added sugars and glycerol. The ciliastat proposal was drastically diminished in importance by the findings in the 1960s that only a relatively small proportion of the ciliastats reached the smoker's cilia. During that time, pertinent skills and competencies in research on tobacco smoke composition, particularly the PAH fraction, have been developed. Such skills permitted the isolation in crystalline form of 14 PAHs and the quantitation of these and many other PAHs. They were also used to put in perspective the pyrogenesis of PAHs from a) specific tobacco components, b) additives, and c) processed tobaccos (reconstituted tobacco sheet [RTS], expanded tobacco). R.J. Reynolds Tobacco Company (RJRT) pioneered the use of RTS (1953) and expanded tobaccos (1969) in cigarette blends and generated much previously unpublished data on the effect of such processed tobaccos on MSS composition.
Characterization of Virginia Tobaccos by Chemometric Methods
Authors: Apostolova E , Dagnon S , Edreva A
Published: July 2016

Leaf samples of different flue-cured Virginia tobacco varieties were analyzed and compared to a standard, the typical American Virginia cultivar K 326. Plants were grown in the Plovdiv region, Bulgaria, under conditions appropriate for Virginia varieties. The tobaccos were characterized by means of high performance liquid chromatography (HPLC) of polyphenols and capillary gas chromatography (CGC) of the neutral volatiles of essential oils, as well as by a sensory evaluation of color and aroma. All cultivars examined contained twelve polyphenol components in their HPLC profiles and differed only in quantitative aspects. Both qualitative and quantitative variations between the CGC profiles of essential oils of the cultivars were observed. The chromatographic profiles of polyphenols and essential oils were compared by the pattern recognition method (PRM) and used for calculating the similarity indexes (Is
,%) of the samples to the standard Virginia variety K 326. The chemometric data obtained are completely compatible with sensory evaluation of color and aroma. Based on the results obtained the tobaccos may be distinguished as: typical full-flavored Virginia - aromatic (Virginia 330); typical full-flavored Virginia - less aromatic (Virginia 0454); non-typical (filler type) Virginia (Virginia 42). The possibilities of the PRM for objective evaluation of color and aroma of Virginia tobaccos were demonstrated.
Bacillus thuringiensis (Bt) for the Control of Insect Pests in Stored Tobacco: A Review
Authors: Blanc M , Kaelin P , Gadani F
Published: July 2016

Among the insect species causing infestations and serious damages to stored commodities, the cigarette beetle, Lasiodermaserricorne (F.) and the tobacco moth, Ephestiaelutella (Hübner) are the major pests of both raw and manufactured tobacco. Post-harvest tobacco control is achieved through sanitation, insect monitoring, and fumigation with phosphine. However, insect resistance to phosphine and control failures have been reported, and increasing regulatory pressure is being exerted on fumigants. Biological control agents such as Bacillus thuringiensis (Bt) appear to be environmentally sound and potentially viable alternatives to chemical control. Bt is a bacterium that produces insecticidal crystal proteins during the sporulation phase and has been, for more than 40 years, the microorganism of choice for the biocontrol of phytophagous insect pests. It produces insecticidal crystal proteins that display specific activity against certain orders of insects and become active upon ingestion by the insect. Our laboratory has conducted extensive research and worldwide surveys to evaluate the presence of Bt in stored tobacco and has confirmed previous findings indicating that Bt may be considered part of the naturally occurring phylloplanemicroflora. Several Bt strains were isolated from tobacco and characterized by DNA and protein profiling. The insecticidal activity of selected strains and of two commercial products against the larvae of L. serricorne was determined by diet incorporation assays. Moreover, the stability of Bt spores and crystal proteins on cured tobacco leaves was assessed over a storage period of time of 30 months. Cigarette prototypes were made with Bt-treated tobacco. Standard cigarette and smoke evaluations did not show any significant difference between the test and control cigarettes. Although the tested Bt strains and products did not yield satisfactory levels of mortality at the required times and doses, the experimental results summarized in the present review indicate that B. thuringiensishas potential for the control of the cigarette beetle. The integration of conventional control approaches with novel systems based on biological agents with different modes of action should offer new avenues for the effective management of stored tobacco pests in line with integrated pest management (IPM) concepts.
Some Studies of the Effects of Additives on Cigarette Mainstream Smoke Properties. I. Flavorants
Authors: Rodgman A
Published: July 2016

Examination of extensive laboratory data collected during the past four decades, particularly considerable unpublished data generated between the mid-1950s and the late 1970s, indicates that none of the materials used as flavorants on smoking tobacco products, particularly cigarettes marketed by a US manufacturer, imparts any significant adverse chemical or biological properties to the mainstream smoke (MSS) from flavorant-treated tobacco, a conclusion reached by Doull et al. (1) in their assessment of available information on nearly 600 ingredients variously used as cigarette tobacco additives in the US Tobacco Industry. In a more recent detailed assessment of the chemical and biological properties reported in the published literature for the MSS from cigarettes fabricated with tobacco with or without one or more additives, Paschke et al. (2) reached a similar conclusion; namely, that in general, no significant increase in the biological activity (carcinogenicity, mutagenicity, and cytotoxicity) of tobacco was reported from cigarettes containing added ingredients. Many flavorful tobacco additives listed by Doull et al. are structurally identical with or similar to highly polar, volatile components identified in the aqueous alcohol-soluble portion of cigarette MSS and tobacco. In the late 1950s, nearly two decades before the precise nature of the aqueous alcohol-soluble components of tobacco was defined, it was determined that their addition to cigarette tobacco produced no significant increase in the cigarette MSS of either the total polycyclic aromatic hydrocarbon (PAH) content or the benzo[a]pyrene (B[a]P) content, MSS components of considerable interest at that time.
A Mathematical Model of Cigarette Smoldering Process
Authors: Chen P
Published: July 2016

A mathematical model for a smoldering cigarette has been proposed. In the analysis of the cigarette combustion and pyrolysis processes, a receding burning front is defined, which has a constant temperature (~450 °C) and divides the cigarette into two zones, the burning zone and the pyrolysis zone. The char combustion processes in the burning zone and the pyrolysis of virgin tobacco and evaporation of water in the pyrolysis zone are included in the model. The hot gases flow from the burning zone, are assumed to go out as sidestream smoke during smoldering. The internal heat transport is characterized by effective thermal conductivities in each zone. Thermal conduction of cigarette paper and convective and radiative heat transfer at the outer surface were also considered. The governing partial differential equations were solved using an integral method. Model predictions of smoldering speed as well as temperature and density profiles in the pyrolysis zone for different kinds of cigarettes were found to agree with the experimental data. The model also predicts the coal length and the maximum coal temperatures during smoldering conditions. The model provides a relatively fast and efficient way to simulate the cigarette burning processes. It offers a practical tool for exploring important parameters for cigarette smoldering processes, such as tobacco components, properties of cigarette paper, and heat generation in the burning zone and its dependence on the mass burn rate.
Some Studies of the Effects of Additives on Cigarette Mainstream Smoke Properties. II. Casing Materials and Humectants
Authors: Rodgman A
Published: July 2016

Examination of extensive laboratory data collected during the past four decades, particularly those unpublished data generated in the 1950s and 1960s, indicates that none of the materials used as casing materials (sugars, licorice, cocoa) and humectants (glycerol, propylene glycol, other glycols) on smoking tobacco products, particularly cigarettes, imparts any significant adverse chemical or biological properties to the mainstream smoke (MSS) from cased and humectant-treated tobacco, a conclusion reached by Doull et al. (1) in their assessment of available information on nearly 600 flavorant, casing material, and humectant ingredients variously used as cigarette tobacco additives in the U.S. Tobacco Industry. Addition of casing materials and humectants to the cigarette tobacco blend produced no significant increase in the cigarette MSS of either the total polycyclic aromatic hydrocarbon (PAH) or the benzo[a]pyrene (B[a]P) content, MSS components that have been of considerable interest for many years. Examination of the transfer of humectants from the humectant-treated tobacco to cigarette MSS indicates that the humectants act as significant diluents to the remaining MSS particulate-phase components generated from the tobacco during the smoking process. This dilution decreases the effects observed in several bioassays, e.g., mutagenicity determined in the Ames Salmonella typhimurium test.