BALM, LEMON
Source: Melissa officinalis L. (Family
Lamiaceae).
Common/vernacular names: Balm, bee
balm, common balm, lemon balm, melissa,
and melissa balm.
GENERAL DESCRIPTION
An aromatic perennial herb with yellowish
or white flowers, up to approximately 1 m
in height, growing in the Mediterranean
region, western Asia, southwestern Siberia,
and northern Africa; widely cultivated. Parts
used are the dried leaves often with flower-
ing tops; an essential oil is obtained from
these by steam distillation. Bees are attracted
to the plant and bruising the leaves releases a
lemony odor.
CHEMICAL COMPOSITION
Contains about 0.1–0.2% volatile oil com-
posed mainly of oxygenated compounds such
as citral (a mixture of neral and geranial),
caryophyllene oxide, citronellal, eugenol
acetate, and geraniol, plus smaller amounts
of terpenes, includingtrans- and ()-b-oci-
mene, caryophyllene,a-cubebene, copaene,
andb-bourbonene.1–5Other constituents of
lemon balm include polyphenols (caffeic
acid, protocatechuic acid, etc.); a tannin
composed of caffeic acid units;6–9flavonoids
(rhamnazin,^10 luteolin, luteolin 7-O-beta-D-
glucopyranoside and other luteolin glycosides;
apigenin 7-O-beta-D-glucopyranoside);^11 ros-
marinic acid;^10 triterpenoids (ursolitc acid,
etc.); and glucosides of geraniol, nerol,
eugenol, benzyl alcohol, b-phenylethyl
alcohol, neric acid, and geranic acid, among
others (KARRER).6,9,12,13The main constituents
of the essential oil are geranial, neral,
citronellal, geranyl acetate, citronellol, and
b-caryophyllene.^14
PHARMACOLOGY AND BIOLOGICAL
ACTIVITIESExtracts of balm have shownin vitroantiviral
activity against HIV-1,^15 herpes simplex,^16
Newcastle disease virus, paramyxovirus
(mumps virus), vaccinia, and other viruses.
The active constituents include polyphenols
(other than caffeic acid) and tannin.7,8
Extracts of balm have also shownin vitro
antioxidant activity against lipid peroxida-
tion;^17 in vitro antithyrotropic activity;18,19
and antiulcerogenic activity in rats against
indomethicin-induced ulcer formation.^20
Balm oil has shownin vitroantitrypano-
somal^21 and antibacterial activity against
Mycobacterium phleiandStreptococcus he-
molytica,^5 as well as antifungal activity,^22
including activity against food spoilage
yeasts.^23 In vitroantihistaminic and antispas-
modic activities from the oil have also been
reported. Antispasmodic activity is attributed
to the presence of eugenol acetate5,24and to
citral. Both the essential oil and citral inhibited
acetylcholine- and serotonin-induced contrac-
tions of rat ileum.^14 In vitroCNS receptor
binding studies of lemon balm extracts have
found nicotinic^25 and muscarinic receptor
activities.^26
A randomized double-blind, placebo-con-
trolled clinical trial of the essential oil as an
aromatherapy in the treatment of patients with
severe dementia found significant improve-
ments in quality of life and agitation scores
from the oil compared to placebo.^27 Another
placebo-controlled, randomized double-blind
trial examined the benefits of a liquid extract
preparation of lemon balm (60 drops/day) in
patients with mild to moderate Alzheimer’s
disease. Patients in the active treatment groups
showed significantly less agitation and im-
proved cognitive function compared to place-
bo.^28 An acute 600 mg dose of an encapsulated
extract of lemon balm in healthy young adults
in a placebo-controlled, double-blind study
found significant improvement in their accura-
cy of attention and memory functions and
increased calmness.^29 In a similar study, an
acute 1600 mg dose increased calmness and62 Balm, lemon