CLOVES may provide the next novel drug
for epilepsy, convulsion, toothache,
tuberculosis, measles and erectile
dysfunction.
THE dried flower buds are used in making
the popular local drink, Zobo. But several
studies, including the World Health
Organisation (WHO) monographs on
selected medicinal plants have validated the
folklore uses of cloves in treating microbial
infections such as Staphylococcus aureus,
Mycobacterium tuberculosis (causative
organism for tuberculosis), herpes, polio,
measles virus; epilepsy, seizures,
convulsion, toothache, ulcer, constipation,
sleeplessness (insomnia) and erectile
dysfunction.
Commonly called clove, Syzygium
aromaticum belongs to the plant family
Myrtaceae. The locals, especially in Lagos call
it conophor. It is one of the important herbs
used as an indigenous medicine and spice
in many Asian countries, Africa and other
parts of the world.
According to the World Health Organisation
(WHO) monographs on selected medicinal
plants, Flos Caryophylli, which consists of
the dried lower buds of Syzygium
aromaticum (cloves) are applied externally
or locally for the treatment of toothache,
and minor infections of the mouth and skin;
and also used as an antiseptic for dressing.
The report reads: “Flos Caryophylli of minor
wounds, and, in the form of lozenges, for
sore throats and coughs associated with the
common cold. The essential oil (one to five
per cent) is used in mouthwashes. Uses
described in folk medicine, not supported
by experimental or clinical data include;
treatment of asthma, bleeding gums,
dyspepsia, fevers and morning sickness.”
According to the WHO Monograph, ethanol
(95 per cent) or aqueous extracts of Flos
Caryophylli inhibited the growth in vitro of
Staphylococcus aureus. The juice of the ?
ower bud inhibited the growth in vitro of
Mycobacterium tuberculosis (minimal
inhibitory concentration [MIC] 1:160). The
powdered crude drug inhibited the growth
in vitro of Yersinia enterolitica when added
to the medium at a concentration of one to
three per cent (w/w).
Nigerian researchers have found that
extracts of cloves could be used to treat
convulsion, seizures and sleeplessness. The
study titled “Neurobehavioral effects of
ethyl acetate fraction of Syzygium
aromaticum ” was published in Nigerian
Journal of Pharmaceutical Sciences.
The study reads: “The result of this study
therefore suggest that the ethyl acetate
fraction may not have contained the
bioactive constituents that are useful in the
treatment of epilepsy. However, the fraction
may contain constituents that are beneficial
in potentiating the effects of diazepam in
inducing sleep suggesting sedative activity
of the fraction. ”
Nigerian researchers have also found the
extract of cloves have anti-ulcerogenic and
anti-secretory activity. The study titled
“ Anti-Ulcerogenic and Anti-Secretory
Activity of the N-Butanol Portion of
Syzygium aromaticum in Rat ” was
published in Nigerian Journal of
Pharmaceutical Sciences.
The study reads: “The extract contains
flavonoids, tannins among others that have
proven to stimulate the production of
prostaglandins, which contribute to the
maintenance of basal gastric mucosal blood
flow and mucus secretion that enhance the
mucosal defense integrity and repair of
injury.
“ The extract proved to possess some
phytochemicals, which may contribute to
the observed gastric anti-ulcerogenic and
anti-secretory activity. ”
Nigerian researchers have also used cloves
extracts to treat constipation and ulcer in
animal models. The study titled was
published in Nigeria Quarterly Journal of
Hospital Medicine by E.O. Agbaje of the
Department of Pharmacology, College of
Medicine, University of Lagos (CMUL), Idi-
Araba.
The study reads: “Our present findings
explain the folkloric uses of Syzigium
aromaticum as an anti-ulcer and a purgative
agent as well as its possible mechanism of
action. ”
Indian researchers have demonstrated that
cloves extracts could be successfully used
to treat male sexual disorders. The study
titled “Aphrodisiac effect of 50 per cent
ethanolic extract of Syzygium aromaticum
(L.) on sexual behavior of normal male rats”
was published in BMC Complementary
Alternative Medicine.
The study reads: “Oral administration of the
extract significantly increased the mounting
frequency, intromission frequency;
intromission latency, erections; quick flips,
long flips as well as aggregate of penile
reflexes and caused significant reduction in
the mounting latency and post ejaculatory
interval. The most appreciable effect of the
extract was observed at the dose of 500
mg/kg.
“The results indicated that the 50 per cent
ethanolic extract of Syzygium aromaticum
produced a significant and sustained
increase in the sexual activity of normal
male rats, without any conspicuous gastric
ulceration and adverse effects. Thus, the
resultant aphrodisiac effectivity of the
extract lends support to the claims for its
traditional usage in sexual disorders. ”
According to the WHO monographs on
selected medicinal plants, eugenol, one of
the active constituents of the ?ower buds,
inhibited the growth in vitro of
Staphylococcus aureus, Propionibacterium
acnes (implicated in pimples/acne) and
Pseudomonas aeruginosa, with an MIC of
0.05, 0.05 and 0.80mg/ml, respectively.
In other studies, eugenol had a broad
spectrum of antibacterial activity in vitro,
inhibiting the growth of Clostridium
sporogenes, Enterobacter aerogenes,
Escherichia coli, Klebsiella pneumoniae
(causative organism for pneumonia),
Proteus vulgaris, Pseudomonas aeruginosa,
Salmonella pullorum (implicated in food
poisoning), Staphylococcus aureus,
Streptococcus faecalis and Comamonas
terrigena at various concentrations.
An aqueous extract of the lower buds
suppressed the replication of herpes
simplex virus (HSV) in vitro at a
concentration of 50 mg/ml. An aqueous
extract of the lower buds had antiviral
activity against HSV-1 in vitro (IC50 60mg/
ml), and in mice (250 mg/kg body weight
by gastric lavage).
According to the WHO monographs on
selected medicinal plants, aqueous extract
of the lower buds suppressed the
replication of HSV-1, measles virus and
poliovirus-1 in Vero cells in vitro at a
concentration of 0.5mg/ml. Intragastric
administration of a decoction of the lower
buds (750mg/kg body weight) decreased
HSV-1 genome titres and the severity of HSV
infection in mice with recurring herpetic
lesions induced by ultraviolet light. Eugenol
at a concentration of 0.1 –10 mg/ml
demonstrated antiviral activity against HSV
and adenovirus-6 in vitro. Eugeniin isolated
from the ?ower buds exhibited anti-HSV-1
activity in mice.
Recommended dosage, according to the
WHO monographs on selected medicinal
plants: “Crude drug, extracts, tincture (1:5,
25 per cent ethanol), lozenges and
mouthwash. Store in a well-closed container,
protected from light. Crude drug 3 –5g as an
infusion (preferably taken hot), three times
daily; 25 per cent ethanol extract (1:1) 3 –
5ml; tincture (1:5, 25 per cent ethanol) 10–
25ml.”