Schriften zu Genetischen Ressourcen - Genres

Utilisation of plant genetic resources for valuable raw materials
aspects are limonene, ß-pinene, ?-terpinene, terpinen-4-ol, a-terpineol, and methyl Nmethylanthranilate.
Garlic and onion oils are mainly used in seasoning mixtures for the food industry. The
oils are produced by steam distillation of the crushed bulbs. The oils have a very
strong pungent odour and the main active odour principles are dialkyl- and dialkenyl
polysulfides which are enzymatically produced from the cysteine sulfoxides such as
alliin occurring in garlic. Leek oil is commercially less important. Also here, specific
sulfides and disulfides are responsible for the typical aroma. Due to the very low
yield, this oil is very expensive.
Essential oils are also produced from several trees and shrubs such as cedar wood
oil, eucalyptus oil, and of course from species of the conifer family. Essential oils
produced from grasses such as Cymbopogon nardus (citronella oil), Cymbopogon
flexuosus and Cymbopogon citratus (lemon grass oil), Cymbopogon martinii (palmarosa
and ginger grass oil), as well as Vetiveria zizainoides (vetiver oil) are used either
as starting materials for single fragrance and flavour chemicals or as such in various
perfume formulations.
A large number of Mentha species, subspecies and varieties are used for essential
oil production such as peppermint, spearmint, pennyroyal, cornmint and M. citrata oil.
Among the lavender plants used for cosmetic products, three are particularly important:
French lavender (Lavandula angustifolia), spike lavender (L. latifolia) and the
hybrid of these two species.
Sage oils are used in fairly large amounts in the fragrance industry, they are obtained
predominantly from Salvia sclarea (clary sage), S. officinalis, S. lavandulifolia (socalled
Spanish sage oil) and S. triloba (Greek sage oil).
To obtain the essential oils, the crushed plant material is distilled with steam or extracted
with a solvent, depending upon the material in question and the desired product.
Since many of the valuable plant substances are thermo-labile or sensitive to
acids, the composition and quality of the isolated products depends strongly on the
individual applied process. In order to minimise the amount of such artefacts, today
also supercritical carbon dioxide extraction is used, which possesses very good solubility
properties and leave no problematic residues (Ziegler 1982). Furthermore in
most cases the resulting products represent a more authentic sensory impression of
the extracted plant material.
The production of lavender oil from the wild plant Lavandula angustifolia is closely
connected with the city of Grasse, which was the centre of perfume manufacture
during the Middle Ages. The collecting of fragrance raw materials such as wild lavender
was performed by the peasants who lived in the area of Grasse. At that time
many of them bought travelling copper stills to produce the lavender oil directly in the
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