Terpeneless Lemon Oil Monoterpenes Remove

reduction carvacrol

(+)-menthofuran

(+)-neoisomenthol

(+)-neoisomenthol

Table 5.1 Volatile oils containing principally terpenoid compounds Major volatile oils have been divided into two groups. Those oils containing principally chemicals which are terpenoid in nature and which are derived by the deoxyxylulose phosphate pathway are given in Table 5.1 below. Oils which are composed predominantly of aromatic compounds which are derived via the shikimate pathway are listed in Table 4.1 on page 139. The introductory remarks to Table 4.1 are also applicable to Table 5.1.

Oils Plant source Plant part used Oil content (%) Major constituents with Uses, notes typical (%) composition

Bergamot

Camphor oil

Caraway Cardamom

Citrus aurantium ssp. bergamia (Rutaceae)

Cinnamomum camphora (Lauraceae)

Carum carvi (Umbelliferae/Apiaceae) Elettaria cardamomum (Zingiberaceae)

fresh fruit peel (expression)

wood ripe fruit ripe fruit

limonene (42) linalyl acetate (27) y-terpinene (8) linalool (7)

(+)-carvone (50-70) limonene (47) a-terpinyl acetate (25-35) cineole (25-45) linalool (5)

flavouring, aromatherapy, perfumery also contains the furocoumarin berg apten (up to 5%) and may cause severe photosensitization (see page 146) soaps flavour, carminative, aromatherapy flavour, carminative, ingredient of curries, pickles

('Continued overleaf )

Table 5.1

Oils

Plant source

Plant part used

Chamomile (Roman chamomile)

Chamaemelum nobile (Anthémis nobilis) (Compositae/Asteraceae)

dried flowers

Citronella

Coriander

Cymbopogon winterianus C. nardus

(Graminae/Poaceae) Coriandrum sativum (Umbelliferae/Apiaceae)

fresh leaves ripe fruit

Dill

Eucalyptus

Eucalyptus (lemon-scented)

Anethum graveolens (Umbelliferae/Apiaceae) Eucalyptus globulus E. smithii E. polybractea (Myrtaceae) Eucalyptus citriodora (Myrtaceae)

ripe fruit fresh leaves fresh leaves

('Continued)

Major constituents with typical (%) composition

Uses, notes

0.4-1.5 aliphatic esters of angelic, tiglic, isovaleric, and isobutyric acids (75-85) small amounts of monoterpenes 0.5-1.2 (+)-citronellal (25-55)

geraniol

(+)-citronellol (10-15) geranyl acetate (8) (20-40) 0.3-1.8 (+)-linalool (60-75)

y-terpinene (5) a-pinene (5) camphor (5) 3-4 (+)-carvone (40-65)

1-3 cineole (= eucalyptol)

flavouring, aromatherapy blue colour of oil is due to chamazulene (see page 196)

perfumery, aromatherapy, insect repellent flavour, carminative flavour, carminative flavour, antiseptic, aromatherapy

citronellal (65-85)

perfumery

Ginger

Zingiber officinale (Zingiberaceae)

dried rhizome

Juniper

Juniperus communis (Cupressaceae)

dried ripe berries

Lavender

Lavandula angustifolia L. officinalis (Labiatae/Lamiaceae)

fresh flowering tops

Lemon

Citrus limon (Rutaceae)

dried peel from fruit

(expression)

1.5-3 zingiberene (34)

(5-sesquiphellandrene (12) (5-phellandrene (8) (5-bisabolene (6)

0.5-2 a-pinene (45-80) myrcene (10-25) limonene (1-10) sabinene (0-15)

0.3-1 linalyl acetate (25-45)

linalool (25-38)

P-pinene (8-12) y-terpinene (8-10) citral (= geranial + neral) (2-3)

flavouring the main pungent principles in ginger (gingerols) are not volatile flavouring, antiseptic, diuretic, aromatherapy juniper berries provide the flavouring for gin perfumery, aromatherapy inhalation produces mild sedation and facilitates sleep flavouring, perfumery, aromatherapy terpeneless lemon oil is obtained by removing much of the terpenes under reduced pressure; this oil is more stable and contains 40-50% citral

('Continued overleaf )

Table 5.1

Oils

Plant source

Plant part used

Lemon-grass

Matricaria (German chamomile)

Cymbopogon citratus (Graminae/Poaceae) Matricaria chamomilla (Chamomilla reçutica) (Compositae/Asteraceae)

fresh leaves dried flowers

Orange (bitter)

Citrus aurantium ssp. amara (Rutaceae)

dried peel from fruit

(expression)

Orange (sweet)

Citrus sinensis (Rutaceae)

dried peel from fruit

(expression)

('Continued)

Oil content (%) Major constituents with Uses, notes typical (%) composition

the main flavour and odour comes from the minor oxygenated components terpeneless orange oil is obtained by removing much of the terpenes under reduced pressure; this oil contains about 20% aldehydes, mainly decanal citral (= geranial + neral) (50-85)

(-)-a-bisabolol (10-25%) bisabolol oxides A and B (10-25%)

chamazulene (1-15%) (+)-limonene (92-94) myrcene (2)

perfumery, aromatherapy flavouring dark blue colour of oil is due to chamazulene flavouring, aromatherapy

flavouring, aromatherapy

Orange flower (Neroli)

Citrus aurantium ssp. amara (Rutaceae)

fresh flowers

Peppermint Pine

Pumilio pine

Mentha x piperita fresh leaf

(Labiatae/Lamiaceae)

Pinus palustris or other needles, twigs

Pinus species (Pinaceae)

Pinus mugo ssp. pumilio needles

(Pinaceae)

0.1 linalool (36)

(5-pinene (16) limonene (12) linalyl acetate (6) 1-3 menthol (30-50)

menthone (15-32) men thy 1 acetate (2-10), menthofuran (1-9) a-terpineol (65)

0.3-0.4 a- and P-phellandrene (60) a- and (5-pinene (10-20) bornyl acetate (3-10)

the main flavour and odour comes from the minor oxygenated components terpeneless orange oil is obtained by removing much of the terpenes under reduced pressure; this oil contains about 20% aldehydes, mainly octanal and decanal, flavour, perfumery, aromatherapy flavouring, carminative, aromatherapy antiseptic, disinfectant, aromatherapy inhalant the minor components bornyl acetate and borneol are mainly responsible for the aroma

(Continued overleaf )

Table 5.1

Oils

Plant source

Plant part used

Rose (attar of rose, otto of rose)

Rosa damascena, gallica, R. alba, and R. R. centifolia (Rosaceae)

fresh flowers

Rosemary

Rosmarinus officinalis (Labiatae/Lamiaceae)

fresh flowering tops

Sage

Salvia officinalis (Labiatae/Lamiaceae)

fresh flowering tops

Sandalwood

Santalum album (Santalaceae)

heartwood

('Continued)

Major constituents with typical (%) composition

Uses, notes

0.02-0.03 citronellol (36)

geraniol (17) 2-phenylethanol (3) C14—C23 straight chain hydrocarbons (25)

camphor (5-22) cineole (5-14) ß-caryophyllene (10) limonene (6)

4.5-6.3 sesquiterpenes:

perfumery, aromatherapy perfumery, aromatherapy aromatherapy, food flavouring perfumery, aromatherapy

Spearmint Tea tree

Mentha spicata fresh leaf

(Labiatae/Lamiaceae)

Melaleuca alternifolia fresh leaf

(Myrtaceae)

Thyme

Thymus vulgaris (Labiatae/Lamiaceae)

fresh flowering tops

Turpentine oil

Pinus palustris and other Pinus species (Pinaceae)

distillation of the resin (turpentine) secreted from bark

terpinen-4-ol (30-45) y-terpinene (10-28) a-terpinene (5-13) p-cymene (0.5-12) cineole (0.5-10) a-terpineol (1.5-8)

thymol (40) p-cymene (30) linalool (7) carvacrol (1)

(+)- and (—)-a-pinene (35:65) (60-70) P-pinene (20-25)

flavouring, carminative, aromatherapy antiseptic, aromatherapy an effective broad spectrum antiseptic widely used in creams, cosmetics, toiletries antiseptic, aromatherapy, food flavouring counter-irritant, important source of industrial chemicals residue from distillation is colophony (rosin), composed chiefly of diterpene acids (abietic acids, see page 209)

these various compounds has been established as in Figure 5.16, which illustrates how the stereochemistry at each centre can be established by stereospecific reduction processes on double bonds or carbonyl groups. The pathway also exemplifies that oxygen functions can be introduced into the molecule at positions activated by adjacent double bonds (allylic oxidation), as well as being introduced by quenching of carbocations with water. Thus limonene is a precursor of carvone (the main constituent of spearmint oil from Mentha spicata) as well as menthone and piperitone, initial hydrox-ylation occurring at an alternative allylic site on the ring. Menthofuran exemplifies a further oxidative modification generating a heterocyclic ring. Both pulegone and menthofuran are considered hepato-toxic. Pulegone is a major constituent of oil of pennyroyal from Mentha pulegium, which has a folklore history as an abortifacient. Pulegone is metabolized in humans first to menthofuran, and then to electrophilic metabolites that form adducts with cellular proteins (compare pyrrolizidine alkaloids, page 305).

p-Cymene, and the phenol derivatives thymol and carvacrol (Figure 5.16) found in thyme (Thymus vulgaris; Labiatae/Lamiaceae), are representatives of a small group of aromatic compounds that are produced in nature from isoprene units, rather than by the much more common routes to aromatics involving acetate or shikimate (see also cannabinol, page 85, and gossypol, page 200). These compounds all possess the carbon skeleton typical of monocyclic monoterpenes, and their structural relationship to limonene and the more common oxygenated monoterpenes such as men-thone or carvone suggests pathways in which additional dehydrogenation reactions are involved.

Data on volatile oils containing terpenoid constituents isolated from these and other plant materials are given in Table 5.1. Volatile oils in which the main components are aromatic and derived from the shikimate pathway are listed in Table 4.1, page 139.

Was this article helpful?

0 0
Aromatherapy Natural Scents that Help and Heal

Aromatherapy Natural Scents that Help and Heal

You have probably heard the term Aromatherapy and wondered what exactly that funny word, „aromatherapy‟ actually means. It is the use of plant oils in there most essential form to promote both mental and physical well being. The use of the word aroma implies the process of inhaling the scents from these oils into your lungs for therapeutic benefit.

Get My Free Ebook


Responses

  • sabrina
    Is decanal a terpenoid?
    7 years ago

Post a comment