Transcript Essential Oil Chemistry

Essential Oil Chemistry
Prepared by Christine Rose
Atoms -The building blocks of matter
Atoms are composed of 3 types of particles:
 protons
(positively charged)
 neutrons (no electric charge)
 electrons (negatively charged)
Atoms become different elements
depending on the number and ratio of these
three particles.
The atom
www.csmate.colostate.edu/.../viney_off/ato
m.jpg
The basic elements of essential
oils
Hydrogen-H
The smallest atom
1 proton
1 electron
0 neutrons
Carbon-C
6 protons
6 electrons
6 neutrons
Oxygen-O
8 protons
8 electrons
8 neutrons
https://vinstan.wikispaces.com/file/view/covalent_bonding.gif/46392209
 In
order to become stable, most atoms
bond to share electrons, and thus, form
molecules.
 Hydrogen, Oxygen, and Carbon form
these covalent bonds.
All essential
oils start with
hydrogen and
carbon atoms.
When 5 carbon
atoms join in a
branched chainhead to tail, the
essential building
block in plant
biology is formed.
This 5carbon
molecule is
called an
Isoprene unit
Hydrogen & Carbon
5 Carbon atoms form
an Isoprene Unit
Terpenes are the
largest class of
molecules in essential
oils
formed from isoprene
units
Monoterpenes
composed of two
isoprene units
contain 10 carbon
atoms
Sesqiterpenes
Composed of 3
isoprene units
containing 15 carbon
atoms
Diterpenes
Composed of 4
isoprene units
contain 20 carbon
atoms
Monoterpenes
• Analgesic, bactericidal, expectorant, stimulant
• Examples: Camphene & pinene in cypress, terpinene in
juniper
Sesquiterpenes
• Analgesic, anti-allergic, anti-inflammatory, antiseptic,
hypotensive, spasmolytic
• Farnesene in chamomile & lavender, Beta-caryophyllene
in basil & black pepper
Diterpenes
• Antifungal, expectorant, hormonal balancers, hypotensive
• Sclareol in clary sage
An interesting fact:
diterpene molecules are
too heavy to allow
evaporation in steam
distillation, so are
therefore rarely present in
distilled essential oils!
So, now that we understand terpenes, let us add an oxygen
atom or oxygen-containing functional group to this
terpene molecule and we have a terpenoid molecule.
Physical characteristics of terpenoid
molecules are:
They are very volatile-making inhalation
an effective method for use.
They are very flammable.
They are generally less dense than
water and will float on the surface.
Monoterpenes and sesquiterpenes are not soluble in water. The
molecules in water (H2O) are polar and prefer to attract other
polar molecules. Terpenoids are generally non-polar and,
therefore, will be repelled and float on top of the water (or in the
case of eugenol, which is more dense than water, will sink to the
bottom).
Vegetable oils, however, are also non-polar and will
dissolve the lipophilic (fat-loving) terpenoids.
Ethanol (alcohol in spirits) is another medium used to
dissolve essential oils. This has the added benefit of
dissolving itself in water.
Name
Ending
Main actions
Alcohols
Antiseptic, antiviral,
bactericidal
Aldehydes
Antifungal, antiinflammatory, disinfectant,
sedative
Examples
ol
Borneol, cedrol,
citronellol,
geraniol, linalool
al, aldehyde
Citral, citronellal,
geranial,
valeranal
Essential
Oils
Characteristics
peppermint,
geranium
Relatively stable
lemongrass,
Slightly fruity
aroma, often cause
skin irritation and
allergic reaction
Frankincense
Rare in essential
oils, generally low
volatility
Acids
Anti-inflammatory
ic acid
Benzoic acid,
cinnamic acid
Esters
Antifungal, antimicrobial,
sedative
yl, ate
Benzyl acetate,
linalyl acetate
clary sage,
bergamot,
lavender
Often intensely
fruity odor.
Ketones
Anticatarrhal, cell
proliferant, expectorant,
vulnerary
one
Camphor,
carvone, jasmone,
thujone,
verbenone
camphor,
hyssop,
rosemary,
sage
Stable compounds,
relatively resistant
to metabolism by
the body
Lactones
Anti-inflammatory,
antiphlogistic, expectorant,
febrifuge
one, in
Bergapten,
coumarin
catnip,
jasmine(low)
Generally low
volatility
Oxides
Expectorant, antiinflammatory
ole
Cineole, linalol
oxide, rose oxide
eucalyptus,
anise
Possible respiratory
irritation
Phenols
Analgesic, antiseptic,
bactericidal, disinfectant,
stimulant
ol
Carvacrol,
eugenol, thymol,
cresol
bay, cinnamon,
thyme, clove
Very likely to be
irritating.
Terpenes
Anti-inflammatory,
antiseptic, antiviral,
bactericidal
Bergaptene,
limonene
citrus, pine,
juniper
Susceptible to
spoilage