Analysis Of Selenium Content Of Flue-cured Tobacco In Enshi Tabacco-growing Area And Reduction Of Tar And Other Harmful Components In Cigarette

Enshi flue-cured tobacco in 2007-2008 and Tobacco leaf sprayed with Na2SeO3 as raw material to study Enshi region tobacco selenium content and its relationship with the chemical composition analysis,valence and speciation of selenium in flue-cured tobacco and the role of selenium in harm reduction in cigarettes.The main research content and results are as follows: The selenium content of upper-leaves were 0.304 mg/kg～3.277 mg/kg, the average were 1.034 mg/kg;the selenium content of middle-leaves were 0.153 mg/kg～2.613 mg/kg, the average were 0.969 mg/kg;the selenium content of lower-leaves were 0.377 mg/kg～3.129 mg/kg, the average were 1.148 mg/kg.The changing regularity of selenium content of different grades tobacco were:X2F>B2F>C3F, among them B2F grade has the maximum variation coefficients were 90.89%;Followed by grade C3F 74.26%;X2F has the minimum were 66.10%.Compared the selenium content with other regions of China, the selenium content of tobacco leaves in Enshi city and Xuanen county were significantly higher than other regions.Analysis of variance and multiple comparisons showed that the difference of selenium content of Enshi city tobacco leaves compared with other regions has reached significant or highly significant level. The selenium content in tobacco of Enshi city and Xuanen county can meet the requirements of the development of selenium-enriched cigarette and provide raw materials for cigarette formula design. The relevant relationship of selenium content with major chemical components mineral elements shows that the selenium content were significantly correlated with total sugar and starch, and not significantly correlated with mineral elements.Organic selenium was the mainly state for the selenium exist in tobacco, which accounted for 93.29%-95.57% of total selenium in tobacco leaves, inorganic selenium mainly in the form of hexavalent state, content of 0.426 mg/kg-0.489 mg/kg, tetravalent state selenium was not detected. Ethanol extracted selenium acoount for 5.85%～6.54% of total content selenium; Water-solubled selenium accounted for 11.39%～12.14% of total selenium; Salt-solubled selenium accounted for 20.74%～22.48% of total selenium; Alkali-solubled selenium accounted for 28.49%～30.63% of total selenium;Residue selenium accounted for 2.86%～3.20% of total selenium. The different state of selenium in the proportion of total selenium followed by alkali-solubled selenium, salt-solubled selenium, water-solubled selenium, ethanol-solubled selenium and Residue selenium.The total amount of different state seleniums accounted for 69.33%～74.99% of total selenium.The tobacco leaves have the maximum amount of alkali solubled selenium, selenoprotein was the main existing forms of selenium in flue-cured tobacco.The selenium content of gas-phase were 4.23%～6.44%; gas-solid phase selenium content of 2.09% ~ 3.81%. The selenium in the mainstream smoke of cigarette accounted for 6.65%-9.37% of total selenium content in cigarette. With the increase of selenium content in cigarette the amount of mainstream smoke selenium didn`t increase regularly. Smoke the selenium-enriched cigarette will not cause selenium poisoning, instead can added small amount of selenium to smoker. The selenium has a significant effect on scavenging total particulate matter, tar and solid-phase free radical in cigarette. The amount of total particulate matter between test cigarette and control cigarette decreased by 11.9%-23.6%; tar content decreased by 16.3%～25.2%;solid-phase free radical decreased by 8.93%～30.74%. In addition, the selenium also has a significant scavenging effect on superoxide anion radical, the selenium content was significantly correlated with tha rate of superoxide anion radical scavenging...