24 Chemical composition of essential oils
from different species, hybrids and
cultivars of
Lavandula
Maria Lis-Balchin
Introduction
The chemical composition of the essential oils from different
Lavandula
species, hybrids and
cultivars show not only interspecific differences, but also intraspecific differences, which may
sometimes
be due to climatic, geographical or seasonal differences or due simply to the amount
of watering or fertilization used. It may also depend on variation due to genotypes, which can
occur either in plants growing in close proximity or in plants some considerable distance away,
for example, in different countries. It can also be due to the method of essential oil extraction
and,
in the case of commercial oils, to the degree of blending and adulteration. The many
species, hybrids and cultivars of
Lavandula
have only been studied to a limited extent and many
of these show wide differences in their compositions, while some are apparently very consistent.
The commercial hybrids of lavandin have variable concentrations of 1,8-cineole and camphor,
which are absent
from the most favoured species,
Lavandula angustifolia
P. Miller, but which give
the harsher notes to the lavandins (Table 24.1). The ‘rhodinol content’, consisting of citronellol,
geraniol, nerol, neryl acetate and geranyl acetate, which together amount to a very small per-
centage
of the total composition, give a sweet, rose-like odour to the lavandin oils. The lavandin
hybrids (Table 24.1), originated from France, but were grown in the Po Valley, Italy, and were
found to have a similar composition to those grown in France.
In 1981, Tucker gave the following average percentage composition
of the main components
of cultivars of lavandin (Table 24.2). This showed small differences between the cultivars, the
Table 24.1
Composition of French lavender (ISO 3515) (
L. angustifolia
P. Miller)
compared to lavandin hybrids
Constituent
L. angustifolia proportion
‘Abrialis’
‘Grosso’
‘Super’
Average
Average
Average
Minimum
Maximum
1,8-cineole
—
1.5
8.6
5.2
2.0
Camphor
—
0.5
8.2
5.9
3.0
Lavandulyl
acetate
2
—
—
—
—
Linalool
25
38
30.4
28.4
29.3
Linalyl acetate
25
45
20.8
27.6
30.4
‘rhodinol content’
not 1.5
1.7
2.2
assesed
Source: Piccaglia (1998).
252
Maria Lis-Balchin
main one was in the high concentration of linalyl acetate in ‘Super’ and the apparent absence of
terpinen-4-ol, cis-ocimene and trans-ocimene in this cultivar, however, the analyses had been
done by different groups, which may account for the slight differences.
Spike lavender
L. latifolia
Medicus is the spike oil of commerce. Different authors have presented variable
compositions for spike oil (Lawrence, 1976–8; 1979–80; 1981–7). This is the most important of
the Spanish oils produced commercially and the yield is high, 0.8–1.2 per cent. More than 300
components have been identified (Table 24.3) and the main ones are linalool (19–48 per cent),
1,8-cineole (21– 42 per cent) and camphor (5–17 per cent).
Table 24.4 shows the similarities in the composition of
L. latifolia
(as averages)
published by
different authors in different years, with the exception of linalool.
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