andg, with the last two being predominant),
and others (LIST AND HO ̈RHAMMER).4,11–13
Roasted coffee contains slightly less caf-
feine than green coffee, but contains much
lower concentrations of trigonelline, chloro-
genic acid, tannins, polyamines, proteins, and
sugars, which are degraded and involved in
flavor formation during roasting. The most
important flavor precursors are reported to be
trigonelline, sugars, free amino acids, and
peptides.1,9,10,14
More than 100 aroma compounds have
been identified in roasted coffee, including
such important flavor contributors as furan
derivatives, pyrazines, pyrroles, oxazoles, and
acids (LIST AND HO ̈RHAMMER).1,10
Roasted coffee contains a relatively high
content of niacin, and coffee has been sug-
gested as a source of niacin, for treating
pellagra or niacin deficiency.10,15A cup of
coffee contains about 100 mg caffeine, which
is within the therapeutic dose range.
PHARMACOLOGY AND BIOLOGICAL
ACTIVITIES
The physiological activities of coffee are gen-
erally attributed to its caffeine. Caffeine is a
powerful stimulant of the central nervous
system, respiration, and skeletal muscles;
other activities include cardiac stimulation,
coronary dilation, smooth muscle relaxation,
and diuresis.
Apart from the biological activities of caf-
feine, those of chlorogenic acid (which is pres-
ent in substantial quantities in coffee) should
not be ignored, as chlorogenic acid is reported
tohavestimulant,diuretic,andcholereticprop-
erties (seeartichokeandhoneysuckle); it also
has allergenic properties (MORTON3).
TOXICOLOGY
The fatal dose of caffeine in humans is re-
ported to be 10 g. A dose of 1 g or more would
produce toxic effects, including headache,
nausea, insomnia, restlessness, excitement,
mild delirium, muscle tremor, tachycardia,
and extrasystoles.
In addition to the above well-known activi-
ties, caffeine has been reported to have many
other activities, including mutagenic, terato-
genic, and carcinogenic activities; it is also
reported to cause temporary increase in intra-
ocular pressure, to have calming effects on
hyperkinetic children (effect similar to methyl
phenidate or dextroamphetamine), and to
cause chronic recurrent headache, among
others.16,17More than 50% of the total muta-
genic activity of coffee can be attributed to the
activity of methylglyoxal.^18 Coffee drinking
has also been linked to myocardial infarction
(a kind of blood clot in blood vessels that
supply blood to heart muscles), cancer of the
lower urinary tract (e.g., bladder), ovaries,
prostate, and others.19,20However, most of
these findings were disputed by later reports
(GOODMAN AND GILMAN; MARTINDALE; USD
23rd).15,21,22
Mutagenic activity of coffee is inactivated
by sodium sulfite (completely suppressing the
mutagenicities of the 1,2 dicarbonyls, diacetyl
and glyoxal) as well as by sodium bisulfite and
metabisulfite. Sodium sulfite also inactivates
the phage-inducing activity of coffee. It has
been suggested that sulfites should be added
to coffee to reduce mutagenicity.^23
Coffee (even decaffeinated) is reported to
stimulategastric secretion and should be taken
only with proper precautions (e.g., with cream
or during meals) by individuals with peptic
ulcer (GOODMAN AND GILMAN;MARTINDALE).USESMedicinal, Pharmaceutical, and Cosmetic.
In addition to its use as a central and respi-
ratory stimulant, usually as caffeine, U.S.P.,
and caffeine and sodium benzoate injection,
U.S.P., caffeine is extensively used as an
ingredient in many types of pharmaceutical
preparations, particularly internal analgesics,
cold and allergy products, weight-control
formulations (appetite depressants), and
others.Coffee 223