DETERMINATION OF NATURAL LEVELS OF COUMARIN IN DIFFERENT TYPES OF TOBACCO USING A MASS FRAGMENTOGRAPHIC METHOD

An accurate analytical method for qualitative and quantitative determination of endogenous coumarin in tobacco has been developed. Coumarin is extracted from the tobacco, and the extract obtained is purified by using high-pressure liquid chromatography or thin-layer chromatography. The quantification is performed by gas chromatography-mass spectrometry using a selected ion monitoring technique and C-13-labeled coumarin as internal standard. The detection limit of the method is 0.050-mu-g of coumarin/g of tobacco. Coumarin was estimated in a number of different tobacco types. The concentrations were generally below 1-mu-g/g of tobacco. In fire-cured tobacco, however, the concentration varies between 1.1 and 4.7-mu-g/g. The higher concentrations in this tobacco may be explained by the presence of coumarin in the hickory smoke, which is condensed onto the leaf during the fire-curing process.