Essential oils
alpha-santalene, alpha-bergamotene,
and (Z)-alpha-bisabolene
Opopanax Commiphora erythraea
var.
glabrescens (
C. opobalsamum) (Burseraceae) Bisabol
Myrrh, Balm of Mecca
This is another of the famous resins of the Orient, see also
myrrh
and
olibanum
(frankincense).
All Burseraceans are resinous. The species of the genus
Commiphora
are thorny bushes and small trees. They are important elements of the African
dry-land vegetation. Opopanax is a viscous exudate obtained by breaking
the twigs of
Commiphora erythraea var.
glabrescens, growing
in Somalia (Africa's Horn). It solidifies to brown lumps of a warm-balsamic
and sweet, honey-like fragrance.
A resinoid is prepared by solvent extraction, and steam distillation of
the resin gives an essential oil. They are both used in perfumes of the
Oriental type.
The main constituents of opopanax oil are sesquiterpene hydrocarbons like
alpha-santalene, alpha-bergamotene, and (Z)-alpha-bisabolene [146].
According to Arctander, the olfactory difference between myrrh oil and opopanax
oil is the vegetable-soup-like, slightly animalic-sweet odor of opopanax
oil compared with the medicinal-sharp freshness of myrrh oil.
Etymology: The term "opopanax", meaning "all healing juice",
is a source of confusion, since it is also used for the gum latex from several
umbellifers, e.g. from
Opopanax chironium (
Pastinaca opopanax)
(Umbelliferae), indigenous to the Mediterranean area [147].
(all-E)-alpha-sinensal
2,6,10-trimethyl-2(E),6(E),9(E),11-dodecatetraenal
(+)-limonene
Orange Citrus sinensis (Rutaceae)
Sweet orange
The familiar citrus fruits - orange,
lemon,
grapefruit,
mandarin,
lime fruit,
bergamot,
bitter orange, etc.
- each have their own characteristic aroma. If an orange is peeled in a
railway coupe, it is immediately identified. The peel's oil glands burst
with an aerosol of tiny evaporating droplets, filling the air with the characteristic
smell of orange. As with most citrus oils, (+)-limonene is the major component,
but the distinctive fresh sweetness from the orange peel is mainly due to
the sesquiterpene aldehyde sinensal, especially the isomer (all-E)-alpha-sinensal,
whose odour detection threshold is as low as 0.05 ppb [3].
Orange oil, obtained by cold-pressing of the peels, is made in several countries
in conjunction with orange juice production. It is used in perfumes of the
Cologne type, and as an aroma in soft drinks.
Etymology: The members of the genus
Citrus belongs to the Rutacean
family, named after
rue,
one of its smaller members.
linalool, indol, farnesene, caryophyllene, germacrene d, bicyclogermacrene
Orange Jessamine
Murraya paniculata
(Rutaceae)
Murraya is related to Citrus, and the flowers of Murraya
paniculata, commonly known as Orange Jessamine, are strongly scented
in the direction of citrus flowers although somewhat lighter and greener.
Orange Jessamine is a native of South and Southeast Asia, China and Australasia.
It is a small tropical tree or shrub with un-edible fruits resembling kumquats
but turning red when ripe. It is a popular ornamental. Honey collected from
bee hive colonies foraging on the flowers has a tangy sweet orange undertone.
Rout et al. investigated the volatiles of Orange Jessamine flowers by various
methods and found that the headspace of the live flowers is dominated by
linalool, indole, (E,E)-alpha-farnesene, (E)-caryophyllene, germacrene d
and bicyclogermacrene, whereas the absolute (obtained by pentane extraction
followed by methanol extraction) has manool as the major component together
with phenethyl alcohol, indole, nerolidol, benzyl benzoate and phenethyl
benzoate [308] [309].
Etymology: Lat. paniculata, i.e. the flowers come in panicles.
p.s. The Curry Leaf Tree of India, Murraya koenigii, is a close
relative. The leaves of this tree, also called sweet neem leaves, are used
in many dishes and curries in India and neighbouring countries.
major odorants in sweet marjoram
Oregano
Origanum majorana (Labiatae) Sweet marjoram
There are about twelve species of Origanum, all natives of the
Mediterranean area and the Near East. A lot of cultivars and many hybrids
exist. The influence of climate, season and soil on the composition of
the essential oil is often greater than the difference between the various
species.
The oregano usually preferred as a spice is O. majorana or sweet
marjoram. It has a natural distribution from Egypt and Arabia to India
but is now grown in most of the world. The tops are harvested before flowering,
then dried and comminuted.
The main essential oil components of sweet marjoram are the bicyclic sabinyl
monoterpenes shown: cis-sabinene hydrate, cis-sabinene hydrate acetate,
trans-sabinene hydrate and sabinene. Hydrodistillation of the essential
oil commonly results in artifact formation with high contents of especially
terpinen-4-ol and gamma-terpinene.
The flavour of the related species O. vulgare or wild marjoram
is generally strongly phenolic due to the presence of thymol and carvacrol
[76] [77].
Oregano is a sine qua non of the Italian cuisine. Maybe the dish most
associated with oregano is pizza.
Etymology: Gr. oros, mountain; Gr. ganos, delight.
Orchid
(Orchidaceae)
With more than twenty thousand species, the orchids are by far the largest
group among the monocots.
In everyday speech, orchids are considered to be expensive plants with large,
richly coloured flowers, but many species have flowers of only a few millimetres'
size. A large number of orchids show highly specific adaptation to (or co-adaptation
with) their pollinators. Some are luring male insects by having flowers
mimicing the females in both appearance and pheromone odour.
In accordance with their adaptation to specific pollinators, orchids may
be scented only at specific times during the day or night. And their odours
show a diversification as impressive as their looks - 'overripe cherry-plum-like',
'patchouli-tagetes-like', 'fresh lemony', 'animal-fatty' are a few impressions
from the orchid house in
The
Botanic Garden in Copenhagen. Many perfumes have borrowed from the exotic
connotations of the orchid, but to describe a fragrance as being 'orchid-like'
is completely meaningless without a reference to a specific orchid.
Etymology: Gr.
orchis, testicles, referring to the shape of the
root nodules of the genus
Orchis.
Only two species will be briefly mentioned here (see
vanilla
too!):
major odorants from Nigritella nigra
Nigritella nigra (Orchidaceae)
This orchid, an endangered species in Scandinavia, is common in the Alps.
Its habitat is sunny, dry alpine meadows on calcareous ground at attitudes
of 1000 to 2800 m. It is locally known as Männertreu or Orchis vanillé.
The dark purple flowers are strongly fragrant with a sweet, cocoa-vanilla-shaded
odour.
The scent is based on phenethyl alcohol and benzyl alcohol and additionally
contains a number of compounds also identified in vanilla
and cocoa extracts
- vanillin, vanillyl ethyl ether, phenylacetaldehyde, isovaleraldehyde,
benzyl isovalerate, etc. [33].
Etymology: Lat. niger, black, as the flowers at a distance have
an almost black appearance.
major odorants from Coryanthes kaiseriana
Coryanthes kaiseriana G. Gerlach (Orchidaceae)
Coryanthes kaiseriana, a recently discovered orchid from Costa
Rica and Panama, has been named after Givaudan scientist Dr. Roman Kaiser
for his research in orchid scents. It belongs to a group of so-called
perfume orchids or euglossine orchids, whose pollinators (euglossine bees)
use the orchids' scents in their own reproductive biology. The flowers
are without nectar. The bees collect the scent at A,
fall into the fluid-filled bucket B, and
are forced to leave the orchid at C whereby
it is pollinated.
The scent of C. kaiseriana is dominated by the rare natural compound
N-methyl anthranilaldehyde, or
2-(methylamino)benzaldehyde, which is characterized by a peculiar dusty,
leathery but still sweetish odor, according to Roman Kaiser. The N-dimethyl
analogue is also present. Moreover, traces of the intensely scented (3E,5Z)-undeca-1,3,5-triene
(also known from galbanum)
make a contribution, together with its precursor, (6Z)-dodeca-2,6-dieno-5-lactone.
1,8-cineole and trans-sabinene hydrate are major terpenoids [167].
(-)-cis-gamma-irone
(-)-cis-alpha-irone
Orris root Iris pallida (
I.
florentina) (Iridaceae) Sweet iris
Orris root is the dried rhizome of the sweet iris,
I. pallida.
Since old ages it has been a remedy in folk medicine, and even today it
is sometimes used to chew on for babies getting teeth. The major cultivation
area is near Florence in the Italian province of Tuscany, but for another
chief purpose. The roots upon ageing get a fine
violet-like
odour and are the source of the famous and very expensive orris root oil,
having an outstanding effect in perfumes. The ageing takes several years,
as the active ingredients arise from slow oxidation of triterpenoid compounds
resembling
ambrein.
The most important odorants from orris root are the methylionones (-)-cis-gamma-irone
and (-)-cis-alpha-irone. A high content of
myristic
acid makes the distillate a waxy mass. The yield is as low as 0.2 %
[3] [6].
Etymology: Gr.
iris, rainbow, because of the often richly coloured
flowers of this genus.