Tobacco Compounds Research Articles

Influence of specific tobacco endophytic Bacillus on tobacco leaf quality enhancement during fermentation.

This study aimed to investigate the potential role of endophytic bacteria in tobacco leaves during the fermentation process to enhance the quality of tobacco. We isolated 11 endophytic bacteria from fresh tobacco leaves and selected Bacillus halotolerans NS36 and Bacillus mycoides NS75 based on sensory evaluation, both of which significantly improved the sensory quality of tobacco leaves. Specifically, NS36 decreased offensive taste in tobacco leaves, while NS75 improved the quality by increasing the aroma. Chemical analysis revealed that fermentation with B. halotolerans NS36 significantly decreased the content of irritant compounds such as lignin, cellulose, starch, and pectin. In contrast, fermentation with B. mycoides NS75 reduced the content of cellulose, starch, and protein, while significantly increasing the content of Amadori compounds and glycosides. Through whole-genome sequencing, we predicted enzyme systems related to these chemical changes. B. halotolerans NS36 mainly secreted enzyme systems associated with the degradation of lignin, cellulose, starch, and pectin, thereby reducing irritants in tobacco leaves, diminishing unpleasant tastes, and achieving a more balanced sensory quality. B. mycoides NS75, on the other hand, secreted enzyme systems related to protein and glycoside hydrolysis, increasing Maillard reaction products and glycosylated compounds in tobacco leaves, thus enhancing the aroma quality and quantity. The findings of this study offer a new perspective for the tobacco industry, namely, the use of endophytic bacilli to improve the off-flavors and aroma of tobacco leaves, which could not only enhance the industrial applicability of tobacco leaves but also potentially strengthen the market competitiveness of products. These discoveries lay the foundation for further research and application, especially in the development of new biotechnologies to improve the quality of tobacco products.

Revealing alcoholization-related volatile compounds and determining alcoholization indices in tobacco using GC-IMS coupled with chemometrics

Alcoholization is an integral part of tobacco processing and volatile compounds are key to assessing tobacco alcoholization. In this study, a total of 154 volatiles from nine categories were determined by gas chromatography-ion mobility spectrometry (GC-IMS) from four grades of tobacco, of which 114 were better identified. And then, the dynamic trends of volatile compounds with significant changes in tobacco alcoholization were analyzed. The relevant volatiles with the alcoholization indices (AIs) (R > 0.8) were screened as indicators of tobacco alcoholization. Cinnamyl isobutyrate, linolenic acid alcohol, propanoic acid-M and propanoic acid-D in all tobacco samples were highly correlated with the AIs and tended to increase during the alcoholization process. In addition, linear discriminant analysis (LDA), back-propagation neural network (BPNN) and random forest (RF) classifiers were constructed for discrimination of tobacco AIs. Three classifiers trained with a combination of 20 volatiles achieved satisfactory results with area under the curve (AUC) of 0.95 (LDA), 0.94 (BPNN) and 0.97 (RF), respectively. The RF classifier gained optimal accuracy of 100 % and 96.1 % for the training and test sets, respectively. The study confirmed that GC-IMS can be used to characterize the changes of volatile compounds in tobacco during alcoholization and combined with machine learning to achieve the determination of AIs. The results of the study may provide a new means for the tobacco industry to monitor the alcoholization process and determine the degree of alcoholization.

Investigating the product characteristics and reaction mechanisms of hydrothermal co-liquefaction among the model compounds of sludge and tobacco stems

Model compounds (glucose, cellulose, oleic acid, protein) were used instead of sludge (SD) and tobacco stems (TS) to carry out experimental research on the hydrothermal co-liquefaction. The reaction mechanism of hydrothermal co-liquefaction was discussed and deduced through the characterization and analysis of three-phase products. The results showed that lipids were the major contributors to the production of bio-oil, with bio-oil yields as high as 85.45 %. Cellulose was the primary contributor to the solid residue, with a solid residue yield of up to 21.50 %. The hydrothermal co-liquefaction results of unary and binary model compounds can be used to predict the bio-oil yields of ternary and quaternary model compounds in this experiment. The experiment also observed the Maillard reaction between proteins and carbohydrates, the production of amides between proteins and lipids, the relative amides content increased to 23.10 %. The interactions between lipids and glucose as well as cellulose, which influenced the yields of hydrocarbons, ketones, and esters, the relative content of ketones and hydrocarbons decreased while the relative content of esters increased to 26.28 %. The results of this experiment provided guidance for the co-liquefaction of mixed biomass, and laid a foundation for the discussion of the reaction mechanism in the process of hydrothermal co-liquefaction.

Deep Learning dalam Prediksi Kebiasaan Merokok di Inggris Guna Mendukung Kebijakan Kesehatan Masyarakat yang Lebih Efektif

Smoking is a common practice throughout the world, where a person smokes and inhales the smoke produced from burning tobacco or other tobacco products. This action has become a significant global health issue because of the various health risks. This activity is often considered an addictive habit because nicotine, the psychoactive compound in tobacco, can cause physical and psychological dependence. This research applies Deep Learning methods to predict data on smoking habits in the UK. The dataset used in this research includes information about gender, age, marital status, highest level of education, nationality, ethnicity, income, and region. Through this research using Deep Learning methods, we can examine a complex data set that describes Smoking Habits in the UK. Based on trials with a dataset of 1,691 items, an accuracy of 78% was obtained. This research can provide important insights into the effectiveness of anti-smoking policies that have been implemented and help plan further actions to reduce the prevalence of smoking and its negative impact on society.

Enhanced In Vitro Plant Morphogenesis of Tobacco: Unveiling Indoleamine-Modulated Adaptogenic Properties of Tulsi (Ocimum sanctum L.).

The medicinal plant tulsi (Ocimum sanctum L.) is acknowledged for its invigorating and healing properties that enhance resilience to stress in various human and animal models by modulating antioxidant compounds. While extensive research has documented these effects in humans, the adaptogenic potential of tulsi in stressful in vitro plant systems has not been explored. This study aimed to elucidate the adaptogenic properties of tulsi leaf extract on the in vitro regeneration of tobacco leaf explants through an investigation of the indoleamines at different developmental stages. Shoot regeneration from leaf explants on the medium supplemented with tulsi extract (20%) was compared to the control, and the differences in indoleamine compounds were analyzed using ultra-performance liquid chromatography. Treatment of the explants with the extract resulted in an almost two-fold increase in the number of regenerants after four weeks of culture, and 9% of the regenerants resembled somatic embryo-like structures. The occurrence of browning in the extract-treated explants stopped on day 10, shoots began to develop, and a significant concentration of tryptamine and N-acetyl-serotonin accumulated. A comparative analysis of indoleamine compounds in intact and cut tobacco leaves also revealed the pivotal role of melatonin and 2-hydroxymelatonin functioning as antioxidants during stress adaptation. This study demonstrates that tulsi is a potent adaptogen that is capable of modulating plant morphogenesis in vitro, paving the way for further investigations into the role of adaptogens in plant stress biology.

GCMS Analysis of Bakong Gayo or Gayo Tobacco (Nicotiana tabacum L) Leaves Extract and Pharmaceutical Uses

Tobacco plants are considered more destructive plants than medicinal plants. This research aims to analyze using GCMS (gas chromatography mass spectrometry) the leaves extract of Bakong Gayo or Gayo tobacco (Nicotiana tabacum L) and its pharmaceutical uses. Extraction of Gayo tobacco leaves with chloroform solvent obtained 14 phytochemical compounds in the form of alkaloids, terpenoids and fatty acids. The phytochemical compounds in Gayo tobacco can be used as antibacterial, anticancer, anti-depressant, antioxidant, sedative, aromatherapy based on references and other potential to be developed as a medicinal plant.

Correlation study on microbial communities and volatile flavor compounds in cigar tobacco leaves of diverse origins

To elucidate the significant influence of microorganisms on geographically dependent flavor formation by analyzing microbial communities and volatile flavor compounds (VFCs) in cigar tobacco leaves (CTLs) obtained from China, Dominica, and Indonesia. Microbiome analysis revealed that the predominant bacteria in CTLs were Staphylococcus, Aerococcus, Pseudomonas, and Lactobacillus, while the predominant fungi were Aspergillus, Wallemia, and Sampaiozyma. The microbial communities of CTLs from different origins differed to some extent, and the diversity and abundance of bacteria were greater than fungi. Metabolomic analysis revealed that 64 VFCs were identified, mainly ketones, of which 23 VFCs could be utilized to identify the geographical origins of CTLs. Sixteen VFCs with OAV greater than 1, including cedrol, phenylacetaldehyde, damascone, beta-damascone, and beta-ionone, play important roles in shaping the flavor profile of CTLs from different origins. Combined with the correlation analysis, bacterial microorganisms were more closely related to key VFCs and favored a positive correlation. Bacillus, Vibrio, and Sphingomonas were the main flavor-related bacteria. The study demonstrated that the predominant microorganisms were essential for the formation of key flavor qualities in CTLs, which provided a theoretical reference for flavor control of CTLs by microbial technology.Key points• It is the high OAV VFCs that determine the flavor profile of CTLs.• The methylerythritol phosphate (MEP) pathway and the carotenoid synthesis pathway are key metabolic pathways for the formation of VFCs in CTLs.• Microbial interactions influence tobacco flavor, with bacterial microorganisms contributing more to the flavor formation of CTLs.Graphical

NtERF4 promotes the biosynthesis of chlorogenic acid and flavonoids by targeting PAL genes in Nicotiana tabacum.

Chlorogenic acid (CGA) and flavonoids are important secondary metabolites, which modulate plant growth and development, and contribute to plant resistance to various environmental stresses. ERF4 has been shown to be a repressor of anthocyanin accumulation in grape, but its full roles in regulating the biosynthesis of other phenylpropanoid compounds still needs to be further studied. In the present study, two NtERF4 genes were identified from N. tabacum genome. The expression level of NtERF4a was higher than that of NtERF4b in all the tobacco tissues examined. Over-expression of NtERF4a significantly promoted the accumulation of CGA and flavonoids in tobacco leaves, while silencing of NtERF4a significantly repressed the biosynthesis of CGA and flavonoids. RNA-seq analysis of NtERF4a-OE and WT plants revealed 8 phenylpropanoids-related differentially expressed genes (DEGs), including 4 NtPAL genes that encode key enzymes in the phenylpropanoid pathway. Activation of NtERF4a-GR fusion protein in tobacco significantly induced the transcription of NtPAL1 and NtPAL2 in the presence of protein synthesis inhibitor. Chromatin immunoprecipitation and Dual-Luc assays further indicated that NtERF4a could bind to the GCC box presented in the promoters of NtPAL1 and NtPAL2, thereby activating their transcription. Moreover, ectopic expression of NtERF4a induced the transcription of NtGSK1, NtMYC2, and NtJAZ3 genes, and enhanced the resistance of tobacco seedlings to salt and drought stresses, indicating multiple roles of NtERF4a in plants. Our findings revealed new roles of NtERF4a in modulating the accumulation of phenylpropanoid compounds in tobacco, and provided a putative target for improving phenylpropanoids synthesis and stress resistance in plants.

Accurate and sensitive analysis of sulfur aroma compounds in tobacco by NADES-enhancing HS-SPME Arrow coupled with GC-Orbitrap-MS

The identification and measurement of sulfur aroma compounds (SACs) to precisely describe tobacco quality and style have remained as significant topics in tobacco research for many years. However, the ultra-trace quantification of SACs in complex tobacco matrices poses a considerable challenge in analytical area. In this study, an accurate and sensitive analysis of SACs in tobacco through a natural deep eutectic solvent (NADES) enhancing headspace-solid-phase microextraction (HS-SPME) Arrow combined with GC-Orbitrap was developed. The NADES system composed of choline chloride and D-glucose (CCGlu) in the pretreatment possessed excellent enhancement of HS-SPME Arrow extraction efficiency for natural tobacco targets. To improve selectivity, GC-Orbitrap was applied that prominently reduced chemical interferences from the tobacco matrix, improving confidence in the determination and identification of SACs in tobacco. During method validation, the limit of quantification (LOQ) ranged from 0.07 to 5.97 ng/g, apparently lower than those reported previously. And acceptable accuracies were attained with relative recoveries ranging from 85.4% to 111%. Finally, the developed method was applied to 45 Virginia tobacco samples, and 23 SACs were identified, among which 11 analytes were detected for the first time in this study. The results were preliminarily analyzed using principal component analysis, demonstrating that SACs could be employed as useful variables to characterize the aroma types and geographical origins of tobacco in China, which might be suitable for monitoring tobacco quality.

Nickel-induced transcriptional memory in lung epithelial cells promotes interferon signaling upon nicotine exposure

Exposure to nickel, an environmental respiratory toxicant, is associated with lung diseases including asthma, pulmonary fibrosis, bronchitis and cancers. Our previous studies have shown that a majority of the nickel-induced transcriptional changes are persistent and do not reverse even after the termination of exposure. This suggested transcriptional memory, wherein the cell ‘remembers’ past nickel exposure. Transcriptional memory, due to which the cells respond more robustly to a previously encountered stimulus has been identified in a number of organisms. Therefore, transcriptional memory has been described as an adaptive mechanism. However, transcriptional memory caused by environmental toxicant exposures has not been well investigated. Moreover, how the transcriptional memory caused by an environmental toxicant might influence the outcome of exposure to a second toxicant has not been explored. In this study, we investigated whether nickel-induced transcriptional memory influences the outcome of the cell’s response to a second respiratory toxicant, nicotine. Nicotine, an addictive compound in tobacco, is associated with the development of chronic lung diseases including chronic obstructive pulmonary disease (COPD) and pulmonary fibrosis. Our results show that nicotine exposure upregulated a subset of genes only in the cells previously exposed to nickel. Furthermore, our analyses indicate robust activation of interferon (IFN) signaling in these cells. IFN signaling is a driver of inflammation, which is associated with many chronic lung diseases. Therefore, our results suggest that nicotine exposure of lung cells that retain the transcriptional memory of previous nickel exposure could result in increased susceptibility to developing chronic inflammatory lung diseases.

Effect of Purpureocillium lilacinum on inter-root soil microbial community and metabolism of tobacco

BackgroundNumerous chemical pesticides have been used in agricultural production to combat crop diseases and pests. Despite ensuring certain economic advantages, they have also resulted in issues like environmental contamination, declining soil quality, and pesticide residues. Because biological control is environmentally friendly and difficult to acquire resistance to, it has been used in practice recently.MethodsIn this study, we isolated the endophytic fungus Purpureocillium lilacinum from Portulaca oleracea L., which was previously found to have inhibitory effects on soil pathogens in tobacco fields. To find out how the biocontrol agent P. lilacinum affects soil microorganisms and plant metabolism in tobacco cultivation, we used amplicon sequencing technology and gas chromatography-mass spectrometry to look at the structure of soil microbial communities and the networks of interactions between microorganisms and metabolites in the inter-rhizosphere soil of tobacco fields treated with different amounts of P. lilacinum.ResultsThe findings showed that there was a trend toward less microbial diversity among inter-root microorganisms as solid-state fermentation (SSF) products of P. lilacinum increased; however, submerged fermentation (SmF) had no discernible impact on microbial diversity when compared to the direct use of SSF. Additionally, the relationship between inter-root fungi and volatile compounds in tobacco leaves was dominated by a negative correlation.ConclusionsThe result demonstrated that P. lilacinum’s antagonistic interaction in the inter-rhizosphere microbial community was dominant and valuable for biopesticide application. P. lilacinum can work more effectively on tobacco roots by using SSF products. P. lilacinum’s opposition to fungal colonies may enhance the volatile chemicals in tobacco leaves. These provide some implications for the biocontrol application of P. lilacinum.

Prenatal nicotine exposure during pregnancy results in adverse neurodevelopmental alterations and neurobehavioral deficits.

Maternal tobacco use and nicotine exposure during pregnancy have been associated with adverse birth outcomes in infants and can lead to preventable pregnancy complications. Exposure to nicotine and other compounds in tobacco and electronic cigarettes (e-cigarettes) has been shown to increases the risk of miscarriage, prematurity, stillbirth, low birth weight, perinatal morbidity, and sudden infant death syndrome (SIDS). Additionally, recent data provided by clinical and pre-clinical research demonstrates that nicotine exposure during pregnancy may heighten the risk for adverse neurodevelopmental disorders such as Attention-Deficit Hyperactivity (ADHD), anxiety, and depression along with altering the infants underlying brain circuitry, response to neurotransmitters, and brain volume. In the United States, one in 14 women (7.2%) reported to have smoked cigarettes during their pregnancy with the global prevalence of smoking during pregnancy estimated to be 1.7%. Approximately 1.1% of women in the United States also reported to have used e-cigarettes during the last 3months of pregnancy. Due to the large percentage of women utilizing nicotine products during pregnancy in the United States and globally, this review seeks to centralize pre-clinical and clinical studies focused on the neurobehavioral and neurodevelopmental complications associated with prenatal nicotine exposure (PNE) such as alterations to the hypothalamic-pituitary-adrenal (HPA) axis and brain regions such as the prefrontal cortex (PFC), ventral tegmental area (VTA), nucleus accumbens (NA), hippocampus, and caudate as well as changes to nAChR and cholinergic receptor signaling, long-term drug seeking behavior following PNE, and other related developmental disorders. Current literature analyzing the association between PNE and the risk for offspring developing schizophrenia, attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), anxiety, and obesity will also be discussed.

The transcription factor NtERF13a enhances abiotic stress tolerance and phenylpropanoid compounds biosynthesis in tobacco

The AP2/ERF (APETALA2/ETHYLENE RESPONSE FACTOR) transcription factors play multiple roles in modulating the biosynthesis of diverse specialized metabolites in response to various environmental stresses. ERF13 has been shown to participate in plant resistance to biotic stress as well as in repressing the synthesis of fatty acid. However, its full roles in regulating plant metabolism and stress resistance still remains to be further studied. In this study, we identified two NtERF genes from N. tabacum genome that belong to Ⅸa subgroup of ERF family. Over-expression and knock-out of NtERF13a showed that NtERF13a could enhance plant resistance to salt and drought stresses, as well as promoted the biosynthesis of chlorogenic acid (CGA), flavonoids, and lignin in tobacco. Transcriptome analysis between WT and NtERF13a-OE plants revealed 6 differentially expressed genes (DEGs) that encode enzymes catalyzing the key steps of phenylpropanoid pathway. Chromatin immunoprecipitation, Y1H, and Dual-Luc assays further clarified that NtERF13a could directly bind to the fragments containing GCC box or DRE element in the promoters of NtHCT, NtF3'H, and NtANS genes to induce the transcription of these genes. Knock-out of NtHCT, NtF3'H, or NtANS in the NtERF13a-OE background significantly repressed the increase of phenylpropanoid compound contents caused by over-expression of NtERF13a, indicating that the promotion of NtERF13a on the phenylpropanoid compound contents depends on the activity of NtHCT, NtF3'H, and NtANS. Our study demonstrated new roles of NtERF13a in promoting plant resistance to abiotic stresses, and provided a promising target for modulating the biosynthesis of phenylpropanoid compounds in tobacco.

Identification of key volatile flavor compounds in cigar filler tobacco leaves via GC-IMS

Identification of key volatile flavor compounds in cigar filler tobacco leaves via GC-IMS

Urinary Cotinine: A Promising Marker of Recurrence of Non-muscle Invasive Bladder Tumor

Introduction and objectives: Nicotine is well known to be an addictive compound of tobacco, but it is not primarily carcinogenic. It is metabolized to cotinine, which is considered the best marker of tobacco exposure. Little is known whether recurrence rate of bladder cancer is related to nicotine metabolites eliminated in urine. We aim by this study to evaluate the relation between urinary cotinine level and the recurrence of bladder cancer. Materials and Methods: Between January 2018 and June 2022, a cross sectional study was conducted. Enrolled patients were smokers already diagnosed with non-muscle invasive bladder cancer, treated by resection only, and presenting for a follow up cystoscopy. Included patients had unchanged smoking habits in the day before the procedure, same ethnicity (Caucasians) and no additional professional exposure. Cotinine level was measured on a sample of voided urine before cystoscopy. Tumor recurrence was considered positive independently from the histological type, and was assessed by direct vision cystoscopy. Patients were considered moderate or heavy smokers depending on the level of cotinine in their urine samples (< or > 550 ng/ml respectively). A Fisher Exact Test was used to assess the relationship between variables. Results: A total of 135 patients was included. Mean age was 64 years (range 36 to 78). The mean duration of smoking was 30.3 years. Urinary cotinine level was > 550 ng/ml in 80 patients (59.26%) and < 550 ng/ml in 55 patients (40.74%). Recurrence was identified in 70 patients (51.85%) and was absent in the remaining 65 (48.15%). Recurrence was observed in 68.75% of the heavy smokers and in 27.27 % of moderate smokers. Cotinine level higher than 550 ng/mL was linked to an increased risk of bladder cancer, with a relative risk of 4.16 (p-value < 0,025). Conclusion: High urinary cotinine levels (>550 ng/ml) conveys a 4 folds’ risk for the recurrence of bladder cancer in smokers. Additional prospective studies are needed to better understand the relation between urinary cotinine levels and bladder cancer, and its usefulness in bladder cancer surveillance.

Unraveling the Difference in the Composition/Content of the Aroma Compounds in Different Tobacco Leaves: For Better Use

The composition/content of aroma compounds in tobacco leaves in the different producing areas varies too much, and it is very meaningful to develop advanced analysis techniques to investigate the composition/content-producing area correlation. Here, gas chromatography-ion mobility spectroscopy (GC-IMS) was used to analyze the composition/content of aroma compounds in tobacco samples from eight different producing areas. With this technique, ion mobility spectrum, differential ion mobility spectrum, and fingerprint spectrum were constructed for two-dimensional analysis. Then, the principal component analysis (PCA) and similarity analysis were performed for the eight tobacco samples. The results showed that the GC-IMS can detect 197 volatile aroma compounds in tobacco leaves and 75 of them are well identified. The fingerprint spectrum directly showed the difference in the composition/content of volatile aroma compounds in tobacco leaves from different producing areas. PCA and similarity analysis can clearly distinguish tobacco samples from different producing areas. This work demonstrated that the application of GC-IMS in analyzing the composition/content of aroma compounds in tobacco leaves is efficient. GC-IMS is a very powerful tool to give a direct and visual comparison of the composition/content of aroma compounds in tobacco leaves from different producing areas. The relationship between the composition/content of aroma compounds and producing areas could be established by this advanced technology. This work offers the possibility of planting or grading tobacco with different taste and smell more precisely in the future.

Simultaneous Determination of Nicotine and Phenolic Compounds in Tobacco by Capillary Electrophoresis with Pipette Tip Electrodes

Aim: The aim of this work is to fabricate pipette tip electrodes for the capillary electrophoretic determination of nicotine and phenolic compounds in tobacco. Background: The content of nicotine affects not only the quality of tobacco products but also the health of smokers. Phenolic compounds are important flavor precursors in tobacco. The quantity of phenolic compounds is one of the most important evaluation indicators of tobacco quality. It is of high importance to determine nicotine and phenolic compounds in tobacco for quality control and the health of smokers. Objective: A method based on capillary electrophoresis and amperometric detection was developed for the simultaneous determination of nicotine, rutin, chlorogenic acid, quercetin, ferulic acid, gallic acid, and protocatechuic acid in tobacco leaves. Pipette electrodes were designed and fabricated for their amperometric detection. Method: Nicotine, rutin, chlorogenic acid, quercetin, ferulic acid, gallic acid, and protocatechuic acid were determined by capillary electrophoresis in combination with the detection electrodes that were fabricated by packing the composite of carbon nanotube and epoxy in pipette tips. Results: Detection potentials, the acidity and concentrations of background electrolyte, separation voltages, and injection times were optimized. At a high voltage of 12 kV, separation of the seven analytes could be achieved in less than 11 min in a piece of 40 cm long fused silica capillary with a background electrolyte of 50 mM borate buffer (9.2). Linearity was observed between the peak currents and the concentrations, with the limits of detection ranging from 0.1 to 0.2 μM for the seven analytes at the pipette electrodes. The method was applied in the simultaneous determination of nicotine and phenolic compounds with satisfactory assay results. Conclusions: The pipette tip electrodes were successfully coupled with capillary electrophoresis for tobacco analysis. The CE-AD method provides not only a simple approach for the quality control of tobacco and its preparations but also an alternative technique for the constituent and fingerprint investigation of other plants.

Metabolomics and proteomics revealed the synthesis difference of aroma precursors in tobacco leaves at various growth stages

Tobacco has a high economic value as the largest cash crop worldwide. The quality of flue-cured tobacco is closely related to the overall status of compounds in fresh tobacco leaves, and the aroma precursor plays a key role in the aroma quality of flue-cured tobacco. The untargeted metabolomics and label-free quantitative proteomics analysis of tobacco leaves in three growth stages (root stretching, prosperous growth, and maturation) retrieved 243 metabolites and 4313 proteins (944 differentially expressed proteins), which showed that carbohydrate, amino acid, and fatty acid metabolism varies among the three growth stages. Also, the most of amino acids, organic acids, fatty acids, and polyphenols reduced in the vegetative growth stage, while increased in the reproductive growth stage. On the other hand, alkaloids such as nicotine, nornicotine, and anatabine increased continuously in tobacco leaves during the three growth stages. This study helps us understand the growth and development characteristics of Yun87 flue-cured tobacco in the field before harvest, and it provides a certain omics basis for the industrial crop flue-cured tobacco.

Molecular composition of soil organic matter (SOM) regulate qualities of tobacco leaves

Soil organic matter (SOM) is of vital importance to soil health, and also plays a crucial role in the quality of the crops such as tobacco. However, the link between tobacco quality and SOM chemical compositions is still not well understood. To fill the information gap, we analyzed the quality of tobacco leaves and the corresponding SOM molecular compositions by electrospray ionization (ESI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), that were collected from six different sites in Bijie, Guizhou Province, China. The tobacco quality variedin six sites based on their chemical compositions. SOM compounds had a remarked impact on the quality of tobacco leaves and a distinct difference in SOM composition between low-quality and high-quality tobacco leaves was observed as well. Specifically, 105 common molecular formulas were detected in three SOM compounds of high-quality tobacco, which were more than those in low-quality samples. Although amino sugar, proteins, lipids, tannins, and carbohydrates had a collective influence on the chemical composition of tobacco leaves, the effect contributed by amino sugar and tannins was more prominent. In summary, fully understanding the association between tobacco chemical composition and SOM compounds can provide new insight into the regulation of tobacco quality and the sustainable development of agriculture.

Development and Validation of a Modified QuEChERS Method for Simultaneous Analysis of 250 Flavor Constituents in Tobacco by Gas Chromatography Tandem Mass Spectrometry.

Flavor constituents play an important role in the flavor characteristics of tobacco leaves and cigarettes. Sensitive, selective, and high-throughput multi-analyte analytical methods are needed to satisfy the demand for analyzing trace-level flavor constituents in tobacco. However, trace analysis of multi-targets in a complex tobacco matrix is significantly challenging. This study was undertaken to develop and validate a fast, selective, sensitive, and accurate GC-tandem mass spectrometry (GC-MS/MS) method for the simultaneous analysis of 250 flavor constituents in tobacco using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction procedure and backflushing technique. The samples were extracted with a mixture of acetonitrile and phosphate buffer. GC-MS/MS served as a reliable tool to quantify the flavor constituents due to its high sensitivity, selectivity, and good repeatability. Our evaluation showed that 243 flavor constituents presented good linearity. Average recoveries of 216 target compounds in tobacco ranged from 70 to 120% with RSDs less than 20% at three fortification levels. The limits of quantitation of 225 and 25 compounds were in the range of 2-50 and 51-112 μg/kg, respectively. This method was then successfully applied to the analysis of 15 commercial cigarette samples with different style characteristics. The modified QuEChERS method worked very well for a wide range of flavor constituents that have not been reported by QuEChERS pretreatment previously, and the use of concurrent backflushing offered significant increase in system robustness and sample throughput. The method greatly improved the detection performance and the range of the flavor constituents, and proved to be more accurate, sensitive, selective, convenient, and practical than the reported method, and thus, can be applied in routine analysis. A validated QuEChERS-based GC-MS/MS method for multiple flavor constituents analysis in tobacco was reported for the first time. The use of concurrent backflushing markedly improved the instrument robustness and sample throughput.