Nicotine 
After application of nicotine to mustard green, cotinine was shown 
to be the principal metabolite (Gunther et al., 1959). 
In man, nicotine is metabolized to cotinine, hydroxycotinine, desmethyl- 
cotinine, and other unidentified compounds (Bowman et al., 1959). In other 
studies with c}4. labeled nicotine, the nicotine isomethonium ion was 
isolated from urine after intravenous administration. Similar results were 
obtained with dogs (McKennis et al., 1963). 4-Methylamino-4(3-pyridy1l) 
butyric acid was indicated by some studies (Bennett and Thomas, 1954). In 
other studies, cotinine and y-(3-pyridyl)-8-oxo-N-methylbutyramide were found 
after administration of nicotine to dogs (McKennis et al., 1962). When 
Gt eaadomiy labeled nicotine was administered intravenously to dogs, 95% 
appeared in the urine within 36 hours; and no radioactivity was detectable 
in exhaled air. 
Studies indicated that cotinine was the principal metabolite with 
insects also. However, the number of metabolites found varied; with to- 
bacco wireworm, 1; with cigarette beetle, 2; with differential grasshopper, 
4; and with the housefly, 3 (Self et al., 1964). In German and American 
cockroaches, cotinine was the main metabolite. In the southern armyworn, 
a number of metabolites were found but not identified (Guthrie, 1957). 
Nicotine was oxidized by Arthrobacter oxydans, a soil microorganism. 
The first product of oxidation was identified as (1)-6-hydroxynicotine (Hoch- - 
stein and Rittenberg, 1959b). In subsequent studies, 6-hydroxypseudooxy- 
nicotine was identified and 6-hydroxy-N-methylmyosmine was postulated as 
the intermediate (Hochstein and Rittenberg, 1960). 
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