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Sun W.,Jiangnan University | Zhou Z.,Jiangnan University | Li Y.,Jiangnan University | Xu Z.,China Tobacco Anhui Industrial Corporation | And 2 more authors.
European Food Research and Technology | Year: 2012

Differentiation of tobacco leaves in different plant stalk positions in China was achieved based on basic chemical compounds and neutral volatiles by principal component analysis (PCA). The continuous flow analysis method was used to determine the quantity of the basic chemical compounds (sugars, total nitrogen and nicotine) of 30 samples. The neutral volatiles of tobaccos were analyzed by GC-MS. It was found that the disparity in basic chemical components was not enough to assess the different quality of tobacco leaves. PCA was used to reveal the differences among these three species based on neutral volatile compounds. Tobacco leaves in different positions were differentiated according to the results of PCA. Four principal components were extracted and altogether accounted for exceeding 80 % of the total variances. The first principal component explained 48.1 % of the total variation and was mainly defined by solanone, megastigmatrienone, 5-methylfurfural, furfuralcohol, phenylethylalcohol and benzylalcohol. The second principal component explained 18.1 % of the total variation and was mainly defined by β-ionone and farnesylacetone. The plots of sample loadings showed that a good differentiation on the basis of concentrations of neutral volatiles was achieved. These results demonstrated that neutral volatiles can be used as the useful variables to characterize the tobacco leaves in different positions. © 2012 Springer-Verlag.

Li P.,Hefei University of Technology | Zhu X.,Hefei University of Technology | Hong S.,China Tobacco Anhui Commercial Corporation | Tian Z.,China Tobacco Anhui Industrial Corporation | Yang J.,Hefei University of Technology
Analytical Methods | Year: 2012

A new ultrasound-assisted extraction (UAE) followed by dispersive liquid-liquid microextraction (DLLME) method has been developed for the simultaneous determination of flavoring compounds, including safrole, coumarin, 6-methylcoumarin, 7-metheoxycoumarin, estragole, methyleugenol, pulegone and thujone, in tobacco additives. In this method, the targets were extracted from tobacco additive sample using ethanol by UAE. Then, 0.5 mL of the extract were used for the DLLME. In the DLLME, the target analytes in the extraction solvent were rapidly extracted into a small volume of chloroform and analyzed by chromatography-mass spectrometry (GC-MS). The parameters affecting the DLLME, including type and volume of extraction and disperser solvents, salt effect and extraction time, were investigated and optimized. Under the optimum conditions, the enrichment factors (EFs) ranged from 140 to 208. The linear relationship was obtained in the range of 0.4-928 ng mL -1, which showed satisfactory linearity with correlation coefficients (r 2) over 0.9989 for all the analytes. The limits of detection (LOD) were between 0.04 and 0.24 ng mL -1 and the average recoveries were between 89.9 and 99.7% with relative standard deviations (RSDs) ranging from 2.5 to 6.7% in all cases. The method was successfully applied to the preconcentration and determination of these target compounds in tobacco additives. © 2012 The Royal Society of Chemistry.

Ding S.-H.,Nanjing University of Science and Technology | Ding S.-H.,China Tobacco Anhui Industrial Corporation | Han Z.-J.,Nanjing University of Science and Technology
Xitong Gongcheng Lilun yu Shijian/System Engineering Theory and Practice | Year: 2011

Bass model is the initial-purchase monopolistic model of consumer durables. Competition and repeat purchase exist side by side for the main markets of consumer-durables brand. Based on the research into the innovation diffusion theory and the relevant theories in brand marketing, the paper firstly probes scientifically into the laws of diffusion of consumer-durables brand in the light of the elements of competition and repeat purchase. However, previous researches lacked the research into theoretical basis of the laws of diffusion of brand. And then the author puts forward the Brand-competition Diffusion Model of consumer-durables brand and the Brand Diffusion Model of repeat-purchase brand, and further establishes the Brand Diffusion Model of competition-and-repeat-purchase brand for two consumer-durables brands. And furthermore, the paper analyzes the relations between it and some other models such as MSB Model, GMM Model and the series of brand diffusion models of consumer-durables brand, and analyzes the influence of the change of model parameters on the Diffusion Model of consumer-durables brand. At last, by numerically analyzing the brand diffusion models of competition-and-repeat-purchase brand for two consumer-durables brands, the paper comes to conclusions that the result corresponds to the market reality and it can rationally expound the diffusion process of brands.

Zhu X.,Hefei University of Technology | Xu Y.,China Tobacco Anhui Industrial Corporation | Gao Y.,Hefei University of Technology | Huang L.,China Tobacco Anhui Industrial Corporation
Journal of the Chinese Chemical Society | Year: 2012

The pressurized liquid extraction (PLE) followed by dispersive liquid-liquid micro-extraction (DLLME) has been developed for extraction of volatile components in tobacco. 35 volatile components were detected by gas chromatography mass spectrometry (GC-MS). Methanol-methyl tert-butyl ether (MTBE) (8:2, v/v) was selected as PLE extraction solvent. The optimized DLLME procedure, 3 mL of pure water and 1.0 mL tobacco extract solution, 40 μL of chloroform as extraction solvent, 0.5 mL of acetonitrile as disperser solvent, was validated. Under the optimum conditions, the enrichment factors were in the range of 96-159. The limits of detection were between 0.14 and 0.33 μg/kg. The repeatability of the proposed method, expressed as relative standard deviation, varied between 4.3 and 7.5% (n = 6). The recoveries of the analytes evaluated by fortification of tobacco samples were in the range of 84.7-96.4%. Compared with the conventional sample preparation method for determination of volatile components in tobacco, the proposed method was quick and easy to operate, and had high-enrichment factors and low consumption of organic solvent. © 2012 The Chemical Society Located in Taipei & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Li Y.,Hefei University of Technology | Bian W.,China Tobacco Anhui Industrial Corporation | Yao Z.,China Tobacco Anhui Industrial Corporation | Cheng X.,Hefei University of Technology
Tobacco Science and Technology | Year: 2014

Tobacco-specific N-nitrosamines(TSNAs)are harmful ingredients in tobacco and it is desirable to reduce TSNAs levels in tobacco leaves and cigarette smoke. In this research, a glucose oxidase(GOX)diluent was applied to the wound introduced at the upper part of main stalk during burley tobacco growth. After air-curing, contents of TSNAs and other chemical constituents in the middle leaves were analyzed. Sensory evaluation of the tobacco leaf quality and leaves' grade were also performed. The leaf quality results showed that GOX treatment increased the proportion of superior tobacco leaves. Total TSNAs contents with GOX treatment decreased by 44.31% on average, and the levels of NNK and NNN decreased by an average of 41.59% and 44.96%, respectively. Concentrations of nitrite-N dropped by an average of 49.13% by the treatment, and nicotine and total alkaloids levels dropped by an average of 15.37% and 20.78%, respectively. ©, 2014, Editorial Office of Tobacco Science and Technology. All right reserved.

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