Studies On The Chemical Constituents In Tobacco And Analysis On Humectants And Aroma Components In Cigarettes

The dissertation is composed of four chapters. Chapter 1 described the isolation and identification of phenolic compounds from Nicotiana tabacum L. In the second chapter, we measured the content of humectants in cigarettes. The third chapter analysised the aroma components in mainstream smoke. The last chapter summarized the Nicotiana’s phenolic chemical constituents, pharmacological actions and their physiological functions in tobacco.In chapter 1, the chemical constituents of tobacco leaves of Honghuadajinyuan from Yunnan were studied by using the chromatography techniques. The leaves were extracted by 70% ethanol-water then repeatedly chromatographed on silica gel, Sephadex LH-2 and semi-preparative HPLC. Twenty phenolic compounds were isolated and purified which including five new biphenyl compounds and fifteen kown compounds. Compounds 1-13 were tested for their anti-tobacco mosaic virus (anti-TMV) activities. The results showed that compounds 3 and 5 exhibited high anti-TMV activitieswith inhibition rate of 48.4% and 32.1%, respectively, which were higher than that of positive control (ningnanmycin).In the second chapter, we determined the 1,2-propylene glycol and glycerol in different levels of cigarettes by Gas Chromatography-Mass Spectrometry. Powdered tobacco samples were extracted by methanol for 2 hours directly. A simple analysis method was developed for determination of 1,2-Propylene Glycol and Glycerol by gas chromatography-mass spectrometry with selectedion mode(GC-MS/SIM); Under the optimal conditions, the calibration curves were linear in the range of 0.05～0.75 mg/ml, and the limits of detection(LODs) were in the range of 0.25 and 0.42μg/ml. The spiked recoveries of analytes were 100.5% and 98.6%, RSDs were 1.2% and 2.5%. This method was suitable for the determination of polyol in real tobacco samples with high sensitivity and convenient pre-treatment.The cigarettes in Yunnan were added propylene glycol, glycerin humectants. The contents of 1,2-propylene glycol and glycerol in the samples ranged from 1.22 to 4.90 mg/g,1.28 to 4.00 mg/g, respectively. The contents of propylene glycol are generally higher than that of glycerol. And these contents in one, two, three, four types of cigarettes are in gradually rising trend.The third chapter analysised the aroma components in mainstream smoke at different levels of cigarette. In this paper the aroma components of cigarette smoke on four different classes were analyzed by simultaneous distillation extraction and GC-MS methods. By comparing the difference between the samples’s aroma components, we want to explore the regularity, then provide theoretical reference for flavoring feeding technology.In the last chapter, Nicotiana’s phenolic chemical constituents, pharmacological actions and their physiological functions in tobacco were summarized.