Medicinal and aromatic plants – industrial profiles

1
General introduction to 
the genus 
Lavandula
Maria Lis-Balchin
Lavandula
species (Labiatiae, syn. Lamiaceae) are mainly grown for their essential oils, which are
used in perfumery, cosmetics, food processing and nowadays also in ‘aromatherapy’ products.
The dried flowers have also been used from time immemorial in pillows, sachets etc. for pro-
moting sleep and relaxation. Numerous lavender plants are also sold as ornamental plants for the
garden; these include 
L. latifolia, L. pinnata, L. lanata, L. dentata
and 
L. stoechas
and their numerous
cultivars.
Lavender oil, distilled from 
L. angustifolia
was used extensively in Victorian times as a per-
fume and applied in numerous cosmetic products, but now it is used mainly in combination
with other essential oils and aromachemicals. This species and numerous hybrids/cultivars, for
example, 
Lavandin
‘grosso’ were originally grown in the South of France, but are now grown vir-
tually round the world. True lavender oil, consisting mainly of linalool and linalyl acetate, has 
a very variable composition due to the genetic instability of the oil-producing plants and varia-
tions due to temperature, water quantity, altitude, fertilizers, time of year, geographic distribu-
tion etc. The chemical composition also varies in the numerous hybrids, which produce larger
plants with a higher essential oil yield and which are therefore grown more often.
The essential oil of lavender is often adulterated with other oils or some fractions derived 
from plants containing linalool and linalyl acetate, or with the synthetic components, or the
original oil can be acetylated. There is a problem with recognition of such adulterations,
although enantiomeric columns have been a useful tool in modern detection.
Aromatherapists consider the oil from 
L. angustifolia
as the most beneficial, together with
wild-grown cultivars at high altitude; as yet scientific evidence is lacking for this and all the
numerous medicinal claims made, other than for a possible general relaxing effect after inhala-
tion, produced via the Limbic system. Pharmacological studies have shown a relaxation of
smooth muscles 
in vitro
using animal tissues, with an initial small contraction exhibited by 
L. angustifolia
; the spasmolytic action was apparently mediated through the secondary messenger
cyclic AMP. Studies with animals 
in vivo
have shown a decline in movement after inhalation; in
man, there was a slowing down of mental and physical activities. The main components were
found in the blood after inhalation and these were also active in their own right when inhaled or
massaged into the skin.
Lavandula
species have a variable antimicrobial effect; Spike lavender, containing camphor, is
the most potent; some species have a moderate antifungal action while the antioxidant activity is
very variable. Some species have an acaricidal effect and have low general insecticidal properties.
Lavandula
has a low toxicity: even the strong undiluted essential oil can be used for some burns,
with, anecdotally, beneficial effects on healing, however, cases of allergic airborne contact 
dermatitis have been reported.
New research on 
Lavandula
species has indicated a wide diversity of applications, for example,
the usefulness of 
L. angustifolia
essential oil in the treatment of alopecia.

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