Application of Sargassum fusiforme(Harv.)Setch.Extract in Cigarettes

[Objectives]This study was conducted to investigate the application of Sargassum fusiforme(Harv.)Setch.in cigarettes.[Methods]Tobacco-specific nitrosamines in the smoke of cigarettes added with ethanol extract of S.fusiforme were determined,and the compounds related to the aroma of S.fusiforme were identified by flavor-smelling experiment.[Results]With the addition of the ethanol extract of S.fusiforme,the decrease in the total amount of four tobacco-specific nitrosamines in mainstream cigarette smoke reached 16.42%.The results of the flavor-smelling experiment showed that the aroma of S.fusiforme might be related to(R)-5,6,7,7A-tetrahydro-4,4,7A-trimethyl-2(4H)-benzofuranone,glycerol,ethyl palmitate,methyl palmitate,ethyl linoleate,methyl(Z,Z,Z)-9,12,15-octadecatrienoate,ethyl(Z,Z,Z)-9,12,15-octadecatrienoate,phytol,and tetradecanoic acid.[Conclusions]The ethanol extract of S.fusiforme has the potential function of reducing the content of tobacco-specific nitrosamines in smoke and improving the taste of cigarettes.

Determination of sterols in tobacco leaves by gas chromatography-tandem mass spectrometry

The purpose of the study was to establish an analytical method to simultaneously determine multiple sterols in tobacco leaves rapidly and accurately.In this gas chromatography-triple quadruple tandem mass spectrometry(GC-MS/MS)based method,various conditions for sterols extraction were assessed and the instrumental operation parameters were optimized with 5α-cholane as an internal standard.Using this method,eight plant sterols,namely lanosterol,campesterol,chenodeoxycholic acid,cholesterol,β-sitosterol,stigmasterol,dihydrotachysterol and ergosterol,were separated in less than 30 min.The linear correlation coefficients were over 0.998 9,the low detection limits were in the range of 0.010 3-0.141 4 μg/g.The recoveries were from 87.30% to 115.60%,with low standard deviations.In conclusion,this method demonstrates good repeatability,accuracy,and high sensitivity,and is best suited for rapid analysis of multiple sterols in tobacco leaves.

Performance analysis of a novel tobacco-curing system with a solar-assisted heat pump

A novel tobacco-curing system with a solar-assisted heat pump was proposed.The proposed system has various advantages,such as reducing energy consumption and pollutant emissions and enhancing the stability of system operation.The thermal characteristics of the system under different climate conditions were analyzed,and the economic and environmental benefits of different tobacco-curing technologies were compared.Results indicated that the dehydration rate,the mass flux of exhaust air,and the heat load of the novel tobacco-curing system in different months had similar changes with the baking time,and all reached the maximum in the later stage of color fixing.Compared with the power saving rate of a heat pump tobacco-curing system,that of the novel system reached 25.9%-35.1%.The dry leaf curing cost of the novel system was only 0.86-1.06 yuan/kg,which can reduce the cost by more than 60%compared with traditional coal-burning tobacco-curing systems in China.Compared with other parts of the tobacco leaf,the top leaf had the lowest dry leaf curing cost due to its highest mass of dry leaf.The payback period and the annual CO_(2) emission reduction of the novel system were 3.0-3.7 a and 15586 kg,respectively.

Change of Phosphate Fraction during Composting of Fresh Waste Leaves of Tobacco

Environmental issue has concerned the public with the build-up of soil phosphorus(P) following application of organic manure.This demands a fully understanding of the change of phosphorus during composting of fresh waste leaves of tobacco and finding out the status of P fertilizer in leaf-made manure.This study had shown that water-soluble and HCl-soluble phosphon were the dominant fractions of P in the compost of fresh waste leaves,in the ranges of 19%-41% and 17%-43%,respectively.However,the former declined progressively upon composting time,but the latter increased,indicating transformation of the more vulnerable water soluble P to the more recalcitrant HCl-extractable P.

Gas flow and filter ventilation of an unlit cigarette: model building,numerical solution and experimental validation

Understanding the fundamcntal relationship betwecn gas dilution rate of a cigarette and key cigarette design parameters is important in the overall control of smoke yield.In this work,an equation was derived to express the total gas dilution with the cigarette rod length,cigarette paper air permeability,and the filter ventilation level.The relationship was validated using experimental results.The accuracy of the developed model was dependent on the regression method used,i.e.,linear or a nonlinear.The expression provides a quantitative description of the interactions between filter ventilation level,cigarette length,cigarette circumference and cigarette paper air permeability and the total air dilution at the cigarette's mouth end.

Distribution and molecular variability of four tobacco viruses in China

Dear Editor,Plant viruses cause great economic losses to tobacco production(Dai et al.,2012).Many types of viruses have been reported to infect tobacco plants,including Tobacco mosaic virus(TMV)(Chen et al.,2014),Cucumber mosaic virus(CMV)(Dai et al.,2012),Tobacco

Study on Drying Edible Soya-bean Oil Using Solar Energy

Soya-bean oil （bean dregs） was dried in a solar energy drying system. Characteristics of the process were measured and the corresponding curves were done. The practicability of this process has been discussed. The results showed that the solar drying system could completely meet technological requirements of drying soy-bean oil, and it was feasible in technology to use the solar drying system to dry the vegetable oil.

Stabilizing model predictive control scheme for piecewise affine systems with maximal positively invariant terminal set

An efficient algorithm is proposed for computing the solution to the constrained finite time optimal control （CFTOC） problem for discrete-time piecewise affine （PWA） systems with a quadratic performance index. The maximal positively invariant terminal set, which is feasible and invariant with respect to a feedback control law, is computed as terminal target set and an associated Lyapunov function is chosen as terminal cost. The combination of these two components guarantees constraint satisfaction and closed-loop stability for all time. The proposed algorithm combines a dynamic programming strategy with a multi-parametric quadratic programming solver and basic polyhedral manipulation. A numerical example shows that a larger stabilizable set of states can be obtained by the proposed algorithm than precious work.

Highly efficient electrochemically driven water oxidation by graphenesupported mixed-valent Mn_(16)-containing polyoxometalate

A highly efficient catalyst of graphene-supported mixed-valent Mn_(16)-containing polyoxometalate is reported here by electrochemical strategy. The modified electrode with the catalyst exhibits an excellent electrocatalytic performance for water oxidation, which will contribute to the development of highly efficient catalysts for oxygen evolution.

Gamma-aminobutyric acid mediates the nicotine biosynthesis in tobacco under flooding stress

Gamma-aminobutyric acid( GABA) is a four-carbon non-protein amino acid conserved from bacteria to plants and vertebrates. Increasing evidence supports a regulatory role for GABA in plant development and the plant's response to environmental stress. The biosynthesis of nicotine,the main economically important metabolite in tobacco,is tightly regulated. GABA has not hitherto been reported to function in nicotine biosynthesis. Here we found that water flooding treatment( hypoxia) markedly induced the accumulation of GABA and stimulated nicotine biosynthesis. Suppressing GABA accumulation by treatment with glutamate decarboxylase inhibitor impaired flooding-induced nicotine biosynthesis,while exogenous GABA application directly induced nicotine biosynthesis. Based on these results,we propose that GABA triggers nicotine biosynthesis in tobacco seedlings subjected to flooding. Our results provide insight into the molecular mechanism of nicotine biosynthesis in tobacco plants exposed to environmental stress.

Characterization of particle size distribution of mainstream cigarette smoke generated by smoking machine with an electrical low pressure impactor

Cigarette smoking is a particle-related exposure. Studying the characteristics of the particle size distribution of cigarette smoke can aid in providing knowledge of smoke aerosol attributes. We used an electrical low pressure impactor （ELPI） to measure the particle size distribution of mainstream cigarette smoke generated by a smoking machine and provided a continuum of particle sizes of cigarette smoke from a whole cigarette. The results showed that the aerodynamic diameters （D, geometric mean of a channel） of particles ranged from 0.021 to 1.956 ~m, and the number concentrations were on the order of 105-109 cm-3 for different sizes of particles. The particle number of the size category below 0.1 p,m approximated that of the category 0.1-2.0 Ixm, and the particles in the size category of 0.1-2.0 μm contributed extremely heavily to total particulate mass. In addition, the results with small samples indicated that the tar yields normalized per milligram of nicotine showed an approximately linear increase with increasing concentration of total particles.

Jasmonate mediates salt-induced nicotine biosynthesis in tobacco(Nicotiana tabacum L.)

Jasmonate(JA),as an important signal,plays a key role in multiple processes of plant growth,development and stress response.Nicotine and related pyridine alkaloids in tobacco(Nicotiana tabacum L.) are essential secondary metabolites.Whether environmental factors control nicotine biosynthesis and the underlying mechanism remains previously unreported.Here,we applied physiological and biochemical approaches to investigate how salt stress affects nicotine biosynthesis in tobacco.We found that salt stress induced the biosynthesis of JA,which subsequently triggered the activation of JA-responsive gene expression and,ultimately,nicotine synthesis.Bioinformatics analysis revealed the existence of many Nt MYC2a-recognized G-box motifs in the promoter regions of Nt LOX,Nt AOS,Nt AOC and Nt OPR genes.Applying exogenous JA increased nicotine content,while suppressing JA biosynthesis reduced nicotine biosynthesis.Salt treatment could not efficiently induce nicotine biosynthesis in transgenic anti-COI1 tobacco plants.These results demonstrate that JA acts as the essential signal which triggers nicotine biosynthesis in tobacco after salt stress.

Manganese catalyzed urea and polyurea synthesis using methanol as C1 source

The manganese-catalyzed dehydrogenative coupling between methanol and amines for the synthesis of ureas and polyureas is described. Importantly, catalytic efficiency can be improved by the newly synthesized MACHO ligands. Furthermore, this highly atom-economical protocol demonstrates a broad substrate scope with good functional group tolerance, producing H_(2)as the sole byproduct. Mechanistic studies disclose that formamide is formed through manganese-catalyzed formylation of amine with methanol.Subsequent dehydrogenation affords a transient isocyanate, which is attacked by another equivalent of amine to provide the final product.

Direct benzylation reactions from benzyl halides enabled by transition-metal-free photocatalysis

An SN2-based photochemical strategy using dithiocarbamate anion as catalyst was developed for the activation of benzyl halides,which are extremely challenging to be applied as radical precursors in visible light photocatalysis.With this transition-metal-free and oxidant-free protocol,the benzylation(or cyanomethylation)of various heterocycles including quinoxalin-2(1H)-ones,coumarin,2-phenyl-2H-indazole,1-methyl-5-phenylpyrazin-2(1H)-one,1-(fluoromethyl)cinnolin-4(1H)-one,and 2,4-dibenzyl-1,2,4-triazine-3,5(2H,4H)-dione could be realized(46 examples,up to 98%yield).Importantly,some biologically relevant 3-benzylquinoxalin-2(1H)-ones were also be synthesized under mild conditions.

The RALF1-FERONIA complex interacts with and activates TOR signaling in response to low nutrients

Target of rapamycin(TOR)kinase is an evolutionarily conserved major regulator of nutrient metabolism and organismal growth in eukaryotes.In plants,nutrients are remobilized and reallocated between shoots and roots under low-nutrient conditions,and nitrogen and nitrogen-related nutrients(e.g.,amino acids)are key upstream signals leading to TOR activation in shoots under low-nutrient conditions.However,how these forms of nitrogen can be sensed to activate TOR in plants is still poorly understood.Here we report that the Arabidopsis receptor kinase FERON IA(FER)interacts with the TOR pathway to regulate nutrient(nitrogen and amino acid)signaling under low-nutrient conditions and exerts similar metabolic effects in response to nitrogen deficiency.We found that FER and its partner,RPM1-induced protein kinase(RIPK),interact with the TOR/RAPTOR complex to positively modulate TOR signaling activity.During this process,the receptor complex FER/RIPK phosphorylates the TOR complex component RAPTOR1B.The RALF1 peptide,a ligand of the FER/RIPK receptor complex,increases TOR activation in the young leaf by enhancing FER-TOR interactions,leading to promotion of true leaf growth in Arabidopsis under lownutrient conditions.Furthermore,we showed that specific amino acids(e.g.,Gin,Asp,and Gly)promote true leaf growth under nitrogen-deficient conditions via the FER-TOR axis.Collectively,our study reveals a mechanism by which the RALF1-FER pathway activates TOR in the plant adaptive response to low nutrients and suggests that plants prioritize nutritional stress response over RALF1-mediated inhibition of cell growth under low-nutrient conditions.