The first product of nicotine oxidation by Arthrobacter oxydans, a soil 
microorganism, was identified as (1)-6-hydroxynicotine. In subsequent 
studies, 6-hydroxypseudooxynicotine was identified and 6-hydroxy-N-methyl- 
myosmine was postulated as the intermediate (671, 672, 673). 
Decomposition of nicotine by pseudomonas gave rise to oxynicotine, 
pseudooxynicotine, and 3-nicotinoylpropionic acid (1458). In other studies, 
y-(3-pyridyl)- -methylaminobutyric acid was believed to be an intermediate 
in the biological degradation of nicotine (955). 
Nicotine was incubated with Ps. nicotinopbaga. In addition to pseudo- 
oxynicotine, 3-succinoyl pyridine, 3-succinoyl pyridone-6, and methyl amine 
were also observed. The process of degradation by bacteria was indicated 
as proceeding initially through N-methylmyosmine with direct decomposition 
of the pyridone nucleus (1384, 1385). 
Other sutides have shown that nicotine was degraded by B. nicotianun, 
B. nicotinophagum and B. nicotinovorum. Among the degradation products 
found was N-methylmyosmine. A soil bacterium, probably Pseudomonas, 
converted nicotine to several compounds identified as pseudo oxynicotine, 
3-pyridy1l-3-methyl-aminopropyl ketone, and a compound believed to be 
3-succinoyl pyridine. Decomposition products of the latter were not identi- 
fied (195, 196, 1457, 1486, 1487). 
Nicotine decomposition was accelerated by ultraviolet radiation. The 
rate was greater in solution at pH 9.5 than at acid pH of 6.2 or 2.1. The 
sulfate form was more stable than free nicotine (1103). Autoxidation of 
nicotine gave rise to cotinine (481). 
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