Efficacy of dogonyaro, mango, guava, pawpaw, banana, lime and lemon grass extract in malaria treatment.

Nigerian researchers have identified local
malaria therapy- containing extracts of
dogonyaro, mango, guava, pawpaw,
banana, lime and lemon grass- used by the
Hausa, Yoruba and Ibo communities.
THE rains are here again! They are
associated with increased episodes of
malaria. However, nature has made
provision for the treatment of malaria in
local plants.
A survey of plants commonly used amongst
the three major ethnic groups (Ibo, Hausa
and Yoruba) in Nigeria for malaria therapy
identified neem/dogonyaro (Azadiratcha
indica), mango (Magnifera indica), lemon
grass (Cymbopoggen citratus), guava
(Psidium guajava), pawpaw (Carica papaya),
lime (Citrus limon), and banana (Musa
sapientum).
The survey by researchers at Ahmadu Bello
University, Zaria, and the Nigerian Institute
of Medical Research (NIMR), Yaba, Lagos
State also showed that in addition to the
plants commonly used by the three Nigerian
major tribes for malaria therapy, Guiera
senegalensis and Artemisia maciverae are
more common with the Hausa tribe in
treating malaria.
According to the survey published in Indian
Journal of Traditional Knowledge, bitter leaf
(Vernonia amygdalina), maize (Zea mays)
and cashew are commonly used by the
Yoruba tribe in malaria therapy, while the
Ibo ethnic group in addition to the plants
commonly used by the other two major
tribes for malaria therapy use bitter leaf.
Leaves and the stem bark are commonly
used for malaria therapy; only in few cases
roots are used.
The researchers obtained information on
the preparation, dosage forms,
administration, effectiveness and possible
side effects of the plant preparations in
treating malaria by interviewing herbalists
from the three Nigerian major tribes. They
wrote: “The common dosage form is liquid
administered orally. For higher efficacy,
decoction of two or more plants is
administered. In some of the preparations,
red potash, pineapple, lemon, local gin and
honey may be added. In some cases, the
possible side effects are frequent urinating,
vomiting, sweating and loss of body
weight. ”
According to the researchers, the herbalists
use different additives and solvents in
preparing their formulations, depending on
dosage formulations. They explained:
“ Some of the additives in traditional
formulations may exert therapeutic activity
in addition to being used as adjutants. For
example, the antibacterial and antifungal
properties of honey is well documented,
with the inhibition of growth of organisms
such as Staphylococcus aureus and Candida
albicans. Honey has been shown to be of
great value in treating infected surgical
wounds. Hence, the use of honey in
traditional formulations for treating malaria
might in addition to exerting synergistic
effect, also have a direct therapeutic effect
on many other concurrent diseases.
“The pattern of traditional prescriptions
revealed that about three quarter of the
prescriptions contained composite
remedies. Traditional healers claimed that
the use of multiple plants has a synergetic
effect. The properties of the constituents of
composite remedies could be different from
those of the mixtures considered as a
whole. ”
Are there scientific backings to this malaria
therapy? Before now, numerous studies
have investigated the antimalarial activities
of neem tree. The leaf extract appears to
have antiretroviral activity and there are
efforts underway to use water extract of
the leaf to develop new drug thrapies. The
plant leaves contain the lemonoid gedunum,
which has demonstrated activity against
two clones of Plasmodium falciparum
(caisative agent of malaria) and in
laboratory analysis appeared to be as
effective as chloroquine. In addition to
viewing the properties of neem tree as
candidates for treating malaria, the oil from
this plant has been shown to have
insecticidal and insect repellant properties.
A consultant pharmacognocist at the
University of Lagos,
Prof. Olukemi Odukoya, told The Guardian:
“ Neem tree (Azadirachta indica of Meliaceae
family) is also used for drug resistant
strains of falciparum malaria. The
antimalarial activity of neem tree is due to
the
active constituent ’s (Gedunin also a lactone)
ability to induce oxidant stress in
erythrocytes during malaria treatment; this
redox perturbation leads to the death of
the parasite in erythrocytes. ”
Researchers have assessed extracts from
the leaves and root bark of Vernonia
amygdalina for antimalarial activity against
drug-sensitive Plasmodium berghei in mice.
According to the study published in the
British Journal of Biomedical Science, a
standard inoculum of infected erythrocytes
was used, and leaf and root-bark extracts of
500 mg/kg, 250 mg/kg or 125 mg/kg are
used in a four-day suppression test and a
Rane test of established infection. Leaf
extract produced 67 per cent suppression
of parasitaemia in the four-day test, while
root-bark extract produced 53.5 per cent
suppression. These results are significant
when compared to a placebo.
Researchers have conducted phytochemical
screening and antioxidant activities of
some selected medicinal plants- pawpaw,
mango, guava, and bitter- used for malaria
therapy in southwestern Nigeria.
The study was published in Tropical Journal
of Pharmaceutical Research. Oxidative
stress has been shown to play an important
role in the development of anaemia in
malaria. Indeed, increase in total antioxidant
status has been shown to be important in
recovery from malaria.
The ethanolic extracts of the leaves of
pawpaw, stem bark of mango, leaves of
guava and the leaves of bitter leaf, were
used in the present study. The plant parts
commonly used in the locality in malaria
therapy were employed in this study.
All the plants showed potent inhibition of
DPPH radical scavenging activity, guava
being the most potent.
The free radical scavenging (antioxidant)
activities of these plants probably
contribute to the effectiveness of the above
plants in malaria therapy.
A study on antiplasmodial activity of seven
plants used in African folk medicine
published in Indian Journal of
Pharmacology shows that lemon grass
possess great inhibition in the growth of
drug-resistant malaria parasite.
Earlier studies had found lemon grass oil to
be anti-microbial, particular against gram
positive bacteria and fungi. Lemon grass oil
had also been found to be pain killing,
central nervous system depressing, fever
reducing, aids digestion and anti-oxidant.
To treat typhoid, researchers recommend
that lemon grass leaf or is boiled in two
litres of water for 30 - 40 minutes with 25
whole limes, two grape fruits, two unripe
papaw fruits, and two unripe pineapples,
cut garlic and the bark of Alstonia boonei
(alstonia, cheesewood, pattern wood or
stool wood in English; egbu in Igbo; and
awun in Yoruba). However, to make an
infusion for malaria, pour a cup of boiling
water over the lemon grass, let it stand for
five minutes, strain it, and drink it.