Alkaloids

Cola nuts are chewed for the stimulating effect of the alkaloids caffein and theobromine they contain. The cola nut is widely grown in West Africa and has particular uses in the social life and religious customs of the people. In Nigeria and Cameroon, four species of cola with edible seed have been distinguished.

• Purine group:
  • Xanthines: caffeine, theobromine, theophylline

here's an excerpt off the net regarding caffeine: http://coffeefaq.com/caffaq.html
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Caffeine is an alkaloid. There are numerous compounds called alkaloids, among them we have the
methylxanthines, with three distinguished compounds: caffeine, theophylline, and theobromine, found
in cola nuts, coffee, tea, cacao beans, mate and other plants. These compounds have different
biochemical effects, and are present in different ratios in the different plant sources. These
compounds are very similar and differ only by the presence of methyl groups in two positions of the
chemical structure. They are easily oxidized to uric acid and other methyluric acids which are also
similar in chemical structure.

Caffeine: Sources: Coffee, tea, cola nuts, mate, guarana. Effects: Stimulant of central nervous
system, cardiac muscle, and respiratory system, diuretic Delays fatigue.

Theophylline: Sources: Tea Effects: Cariac stimulant, smooth muscle relaxant, diuretic, vasodilator

Theobromine: Sources: Principle alkaloid of the cocoa bean (1.5-3%) Cola nuts and tea Effects:
Diuretic, smooth muscle relaxant, cardiac stimulant, vasodilator.