1. The polyphenols of flue-cured tobacco have been found to comprise numerous compounds.

2. The major constituents are rutin (3-rhamno-glucoside of 5:7:3':4'- tetrahydroxy flavonol), the chlorogenic acids, scopoletin (7-hydroxy-6- methoxy coumarin), scopolin (7-glucoside of scopoletin) and an unidentified compound which has a pink fluorescence in ultra-violet light.

3. The polyphenols of tobacco do not contain catechins or leucoanthocyanins which have been found however to be the major constituents of the polyphenols of tea and cacao.

4. No evidence for free caffeic acid could be found in the samples of fluecured tobacco examined.

5. No qualitative differences in the major polyphenols have been found in several samples of flue-cured, tobacco. There are however quantitative differences in the polyphenols.

6. The method of curing employed has a large bearing on the polyphenols present, since in fire-cured and air-cured tobaccos it was found that most of the major polyphenols except scopolin and scopoletin had been destroyed.
 

(Full article published with kind permission from "Tobacco International")