Pyridines from plant sources

Miscellaneous piperidines and pyridines from plant sources... 

Many heterocyclic compounds of complex structure occur in nature, and many have been synthesized. Most of the basic nitrogenous substances which occur in plants and are known as alkaloids are heterocyclic compounds. When coal is subjected to destructive distillation a part of the nitrogen present is converted into ammonia, and a part into cyclic compounds which contain nitrogen as a constituent of the ring. Heterocyclic compounds are also obtained from DippePs oil, which is a product of the distillation of bones. From these sources are obtained pyridine, C5H5N, picoline, CH3.C5H4N, quinoline, C9H7N, etc.. ... 

Source Pyridine occurs naturally in potatoes, anabasis, henbane leaves, peppermint (0 to 1 ppb), tea leaves, and tobacco leaves (Duke, 1992). Identified as one of 140 volatile constituents in used soybean oils collected from a processing plant that fried various beef, chicken, and veal products (Takeoka et al., 1996). 

Prior to 1961, all the factors that catalyzed the photoreduction of pyridine nucleotides had been isolated from either chloroplasts or leaves. The green plant was considered the only source of these proteins. However, in 1961 the association of these proteins with green plants ceased to be unique when Losada, Whatley, and Arnon (64) isolated a similar protein from a photosynthetic bacterium. This bacterial protein replaced the chloroplast protein in the photoreduction of TPN by illuminated spinach chloroplast fragments. 

The enzyme, when isolated from a wide variety of sources, is specific for the A side of the nicotinamide ring 2 3,24). Organisms examined cover the range from mammals and plants (35) to bacteria (26,37). The A side specificity of the dogfish enzyme has been demonstrated by Biellmann and Rosenheimer (28). The )8-glycosidic bond is essential in both parts of the dinucleotide for activity (29). The redox potential of the pyridine nucleotide reaction is —0.320 V (30,31). Enzyme from a given species is specific either for d- or L-lactate. In some lower organisms such as horseshoe crab (32) and E. coli (33) the enzyme is specific for D-lactate, and there are indications that in these cases the active molecule is only a dimer (34). 

---