Zhang Junsong

Contents of Nonvolatile Organic Acids in Flue-cured Tobacco from Main Tobacco Growing Areas in Henan

To investigate the characteristics of nonvolatile organic acid contents in flue-cured tobacco from the main tobacco growing areas in Henan, the contents of nonvolatile organic acids in tobacco samples of different grades from different areas were determined by gas chromatography method and compared. The correlationbetween the content of individual nonvolatile organic acid and the total content of nonvolatile organic acids was analyzed. The cluster analysis of tobacco samples was conducted on the basis of their nonvolatile organic acid contents. The results showed that: 1) The total contents of nonvolatile organic acids in samples ranged from99.32 to 181.90 mg/g with the average of 134.10 mg/g. There existed great variations between different nonvolatile organic acids. 2) The areas in the order of total nonvolatile organic acid content were Jiaxian Xuchang Luoning Shanxian Lingbao Luyi Xiangcheng Lushi Sheqi. 3) The total contents of nonvolatile organic acids in tobacco samples of different grades extremely significantly differed in the order of X2 F B2 F C3 F. 4) The total content of nonvolatile organic acids extremely significantly positively correlated to the contents of malic acid, citric acid and linolenic acid, and significantly positively correlated to malonic acid content. 5) Henan tobacco samples were classified into three categories according to the results of cluster analysis.

Accumulation and Distribution of Pb,Cr,Cu,As,Cd and Hg in Flue-cured Tobacco Leaves Grown in Soil Treated with Six Heavy Metal Solutions

In order to investigate the accumulation and distribution of heavy metals in leaves of flue-cured tobacco treated by heavy metals at different concentrations,the contents of 6 heavy metal elements,including Pb,Cr,Cu,As,Cd and Hg,in 12 groups of representative leaf samples,were determined by ICP-MS with microwave digestion.The results indicated that: 1) The residual contents of Pb,Cr,Cu,and As in leaves decreased towards the higher stalk positions,Cd residue did on the opposite way,however,the Hg residue in leaves did not show significant difference between different stalk positions.2) At the significant difference level of 5%,the treatments in the order of residue contents of Cu,Cr and Hg in leaves were high concentration treatment middle concentration treatment low concentration treatment;the residues of Pb and As in leaves treated at middle and high concentrations were higher than those at low concentration;however,the Cr residue in leaves treated at different concentrations showed no significant difference.The accumulation of heavy metals in leaves increased with the increase of their application rate.

Residue of Butralin in Tobacco and its Transfer Rate into Tobacco Smoke

In order to determine the residue of butralin in tobacco and its transfer rate into smoke,a method for determining butralin with GC-MS/MS is developed.The butralin in sample was extracted with acetonitrile saturated by n-hexane, purified by graphite-amidocyanogen solid phase extraction cartridge,eluted with a mixture of 3∶1(v/v) acetonitrile-toluene,and determined by GC-MS/MS.Twelve flue-cured tobacco samples applied at different butralin rates during growing and their smoke samples were analyzed.The results showed that: 1) The average recoveries of butralin in tobacco and smoke samples were 101.02% and 96.59% with the relative standard deviation of 6.11 % and 6.79% at the limit of detection of 0.87 ng/mL,respectively.2) For the leaves of the same stalk position,the contents of butralin in tobacco and smoke samples increased with the increase of butralin application.3) For the same application rate,the stalk positions in the order of butralin content in tobacco leaf were lowermiddleupper.4) The transfer rates of butralin from tobacco into mainstream smoke ranged from 10.49% to 14.28% with the average of 12.76%.This method is suitable to determining the residues of butralin in tobacco and its transfer rate into smoke.

Determination of Sterols in Tobacco with Capillary Gas Chromatography

The cholesterol,campesterol,stigmasterol and β-sitosterol in 15 samples of flue-cured tobacco leaves and 10 samples of cigarettes were determined. The samples were extracted with acetone,then hydrolyzed in 1% sulfuric acid of ethanol solution,and saponified in 2.0 mol/L potassium hydroxide of alcohol solution,reacted with trimethysilyl chloride and hexamethyldisilazane,and analyzed by capillary gas chromatography.The results showed that: 1) the recovery of these sterols ranged from 94.24% to 101.22% with RSD of 5%;2) the contents of stigmasterol and sitosterol were the highest in all of the samples,no matter whether it was tobacco leaves or cigarette of Virginia type or blended type;followed by campesterol,and chomesterol was the lowest;3) the total sterols in tobacco leaves from the same producing area decreased with the elevation of stalk position;4) the total sterols in Virginia type cigarette was higher than that in blended type one;5) for the same type cigarette,the total sterols in domestic cigarette was lower than that in imported one.

Studies on Fermentation Conditions for Nicotine Dehydrogenase Producing Arthrobacter Z3

Arthrobacter Z3,which produces nicotine dehydrogenase,was isolated from the soil in a disposal site of tobacco dust in the cigarette factory.The culture medium of Z3 was optimized with orthogonal experiment,and its fermentation conditions,including initial pH value,inoculum amount,temperature,rotation speed and fermentation time,were tested.According to orthogonal experiment,the optimum medium composition was 2.5% tobacco dust extract,0.1% soybean powder,0.1%(NH4)2SO4,1.33% K2HPO4·3H2O,0.4% KH2PO4,0.02 % MgSO4·7H2O,0.004% MnSO4·4H2O,and 0.002% CaCl2·2H2O,and the optimum fermentation conditions were:fermenting for 9 h at 30 ℃,rotation speed of the shaker 220 r/min,initial pH 7.0,and inoculum amount 6%.

Effects of Ultra High Pressure Treatment on Flavor Components in Tobacco

In order to improve smoking quality, the flue-cured tobacco lamina was treated under ultra high pressure (UHP, 100-700 MPa) at 30℃, the flavor components in tobacco before and after UHP treatment were isolated by simultaneous distillation and extraction (SDE) and analyzed by capillary gas chromatography, and the smoking quality was evaluated. The results showed that: 1) the total content of flavor components increased with the pressure increasing and peaked at 500 MPa, then decreased; 2) the change trend of ketones was similar to that of the total flavor components; 3) the contents of β-phenylethyl alcohol, benzyl alcohol, eugenol and linalool increased continuously with the increase of pressure, and the contents of phenylacetaldehyde, furfural and 5-methyl furfural peaked at 300 MPa, then somewhat decreased; 4) when the pressure reached 500 MPa, the smoking quality was the best. It was concluded that the flavor quality of tobacco could be improved to a certein extent by ultra high pressure treatment.