Page 61 - Phytochemistry 2 (06-PG 605)

decomposition. Caffeine is soluble in water (1:50), more soluble in
hot water (1:6), in acetone (1:50), in benzene (1:100) and sparingly
soluble in ether. The stability of caffeine in water in increases by
addition of organic acids or their salts e.g. citric acid, sodium
benzoate and salicylate.
Uses
Caffeine is a central nervous system (CNS) stimulant, having the
effect of temporarily warding off drowsiness and restoring
alertness.
Caffeine is the world's most widely consumed (psychoactive)
substance, Most commonly consumed as beverages, such as
coffee, tea, soft drinks and energy drinks that enjoy great
popularity worldwide.
It is the most commonly consumed by humans in infusions
extracted from the seeds of the coffee plant and the leaves of the
tea.

Isolation of caffeine from tea leaves
The powdered tea leaves, is extracted by boiling (refluxing)

with water. The extract is filtered, boiled and treated with lead
acetate solution (precipitation of tannin) and filtered. The excess
lead in the filtrate is removed by addition of sodium hydrogen
phosphate and filtered. The filtrate is concentrated and caffeine is
extracted with chloroform.

Theobromine

Theobromine occurs naturally in seeds of Theobroma cocao
Properties

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