Free and conjugated phytosterols in cured tobacco leaves: influence of genotype, growing region, and stalk position.
Although phytosterols in tobacco leaves have specific effects on tobacco quality, there is little research on the distribution of free and conjugated phytosterols in various tobacco leaves. In this paper, we explored the content and composition of phytosterols in representative cured tobacco leaves by gas chromatography of TMS-ether derivatives. We found that phytosterol contents in tobacco leaves ranged from 1.0 to 2.5 mg/g of dried leaf tissue, depending on different types of tobacco leaves. The majority of phytosterols (75-85%) were conjugated as ester and glycosides, with only about 15-25% existing in the free form. Furthermore, the genetic variability gives rise to the significant differences among different tobacco types with phytosterol levels: the contents of phytosterols in tobacco leaves decreased in the order of flue-cured tobacco, Oriental tobacco, Burley tobacco, cigar tobacco, and Maryland tobacco. At the same time, the tobacco curing process leads to a difference in phytosterol existing-form distribution in some variation laws.
Liu
Wen-Hui
WH
Research Center of Tobacco and Health, University of Science and Technology of China, Hefei, China.
Yong
Guo-Ping
GP
Fang
Li
L
Wang
Shao-Kun
SK
Bai
Hai-Jun
HJ
Jiang
Jia-He
JH
Liu
Shao-Min
SM
D002681:China; D004777:Environment; D004952:Esters / Q000032:analysis; D005838:Genotype; D006027:Glycosides / Q000032:analysis; D010840:Phytosterols / Q000032:analysis* / Q000737:chemistry; D018515:Plant Leaves / Q000033:anatomy & histology / Q000737:chemistry*; D014026:Nicotiana / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development
D004952:Esters; D006027:Glycosides; D010840:Phytosterols