Nornicotine (NN)

Nornicotine is an alkaloid found in various plants including Nicotiana, the tobacco plant. It is chemically similar to nicotine, but does not contain a methyl group. It is a precursor to the carcinogen N-nitrosonornicotine that is produced during the curing and processing of tobacco. Nornicotine is a secondary tobacco alkaloid that is produced by the N-demethylation of nicotine. Nornicotine production and accumulation in tobacco are undesirable because nornicotine serves as the precursor in the synthesis of the well characterized carcinogen N′-nitrosonornicotine during the curing and processing of tobacco. Although nornicotine is typically a minor alkaloid in tobacco plants, in many tobacco populations a high percentage of individuals can be found that convert a substantial proportion of the nicotine to nornicotine during leaf senescence and curing.