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The "Discovery" of Coffee
Legend has it that coffee was "discovered" around850 AD in upper Egypt by a goat herded namedKhaldi. One night, Khaldi's goats did not returnhome. When he found his goats, Khaldi saw themdancing around a shrub with red berries (coffeebeans). After Khaldi tried some of the berries, hestarted to dance too. Khaldi spoke with some monkswho used the berries to make a drink and....coffeewas born!
Other names
- trimethylxanthine- coffeine- theine- mateine- guaranine- Methyltheobromine- 1,3,7-trimethylxanthine
Chemical properties
Alkaloid of the methylxanthine family Pure is bitter, odorless white powderChemical formula - C8H10N4O2
systematic name: 1,3,7-trimethylxanthine or 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-
dione
Metabolism
the first metabolic products: theophylline (4%) – relaxes muscles of the bronchii
theobromine (12%) - the principal alkaloid in cocoa
paraxanthine (84%) - increases lipolysis →elevated glycerol and free fatty acid levels in the blood plasma
has been used as a treatment of asthma
treatment = léčba
principal = hlavní
elevated = zvýšení
fatty acid = mastná kyselina
Metabolism
Adenosine - naturally occurring xanthine, neurotransmitter
- slows down the nerve cell activity
Caffeine - similar molecule to adenosine → binds to the
same receptors → blocks it →increased nerve activity → release of the hormone adrenaline
Effects: higher heart rate
increased blood pressure increased blood flow to muscles decreased blood flow to the skin and inner organs release of glucose by the liver
bind = vázat se
increased = zvýšený
release = uvolnění
heart rate = srdeční tep
liver = játra
Symptoms
Other caffeine effects:• increase alertness• reduce fine motor coordination• cause insomnia • cause headaches, nervousness and dizziness • cause mild diuretic effect• increase the excretion of calcium from the body
increase alertness = zvyšuje bdělostinsomnila = nespavostheadaches = bolesti hlavynervousness = nervozitadizziness = závratědiuretic = močopudný
Symptoms
Masive doses → intoxication
A) 250 mg per day:• nervousness• excitement• insomnia• flushed face• diuresis• gastrointestinal complaints• hallucinations
B) More than 1000 mg per day • muscle twitching• cardiac arrhythmia
= nervozita
= podráždění
= nespavost
= zrudlý obličej
= diuréza (vylučování moči)
= škubání svalů
doses = dávky
Symptoms
Lethal dose - 3 200 mg intravenously
- LD50 = 150 - 200 mg/kg of body mass 170
mg/kg body weight -> the same as drinking 140 to 180 cups of coffee in rapid succession -> not an easy thing to do!
lethal = smrtelný
in rapid succession = rychle za sebou
Half life = generaly around 5 hours
Physical dependence
Some studies show that caffeine causes physical dependence
Withdrawal symptoms: • headache• fatigue• muscle pain
- can occur within 24 hours after the last dose of caffeine
Two studies:1. minimum consumption of caffeine for physical
dependence is 4 cups of coffee per day 2. a few more cups of coffee are needed to develop
dependence.
= abstinenční příznaky
= únava
consumption = spotřeba
dependence = objevit se
= závislost
The effect of caffeine on spider web construction
web of a spider on LSD web of a drug-native spider
web of a spider on caffeine
web of a spider on hashish
Sources
http://faculty.washington.edu/chudler/caff.html http://en.wikipedia.orghttp://www.chm.bris.ac.uk/webprojects2001/tillingwhycaffeine.htm