Composition Studies on Tobacco XXXVIII: Evidence for the Origin of the High Molecular Weight, Acidic Pigment in Cigarette Smoke Condensate

The yields of acidic brown pigment isolated from cigarette smoke collected and stored under various conditions show no significant differences; however, some tendency may exist for a small increase in yield on extended storage of the condensate in traps at -79°C or in acetone solution at room temperature. The molecular weights of subfractions of the pigment are variable when the pigment is immediately isolated from freshly prepared condensate. Storage of condensate results in a higher proportion of high molecular weight subfraction in the pigment in all cases. Both leaf and condensate pigments sublime at high temperature and low pressure yielding a sublimate that contains some subfractions with molecular weights of the same general magnitude as those in the isolated condensate pigment. Nicotine may be acquired as a moiety in the condensate pigment through artifact reactions in the collection system or during the isolation. However, the nicotine acquired in this way apparently represents a very small amount of the total saponifiable nicotine in the pigment. The acetic acid moiety of the condensate pigment is not acquired by such artifact reactions. Although part of the condensate pigment structure may be formed through reactions in the collection system or during isolation, no evidence was obtained that the condensate pigment is largely an artifact.