In vitro antiplasmodial effect of ethanolic extracts of traditional medicinal plant Ocimum species against Plasmodium falciparum.
OBJECTIVE
To identify the possible antiplasmodial compounds from leaf, stem, root and flower extracts of Ocimum canum (O. canum), Ocimum sanctum (O. sanctum) and Ocimum basilicum (O. basilicum).


METHODS
The O. canum, O. sanctum and O. basilicum were collected from Ramanathapuram District, Tamil Nadu and the extraction was carried out in ethanol. The filter sterilized extracts (100, 50, 25, 12.5, 6.25 and 3.125 μg/mL) of leaf, stem, root and flower extracts of O. canum, O. sanctum and O. basilicum were tested for antiplasmodial activity against Plasmodium falciparum (P. falciparum). The potential extracts were also tested for their phytochemical constituents.


RESULTS
The leaf extract of O. sanctum showed excellent antiplasmodial activity (IC(50) 35.58 μg/mL) followed by leaf extract of O. basilicum (IC(50) 43.81 μg/mL). The leaf extract of O. canum, root extracts of O. sanctum and O. basilicum, the stem and flower extracts of all the three tested Ocimum species showed IC(50) values between 50 and 100 μg/mL. Statistical analysis reveals that, significant antiplasmodial activity (P <0.01) was observed between the concentrations and time of exposure. The chemical injury to erythrocytes was also carried out and it shows that, there were no morphological changes in erythrocytes by the ethanolic extract of O. canum, O. sanctum and O. basilicum. The in vitro antiplasmodial activity might be due to the presence of alkaloids, glycosides, flavonoids, phenols, saponins, triterpenoids, proteins, resins, steroids and tannins in the ethanolic extracts of tested plants.


CONCLUSIONS
The ethanolic leaf extracts of O. sanctum possess lead compounds for the development of antiplasmodial drugs.
Department of Oceanography and Coastal Area Studies, School of Marine Sciences, Alagappa University, Thondi Campus, Thondi, Ramanathapuram District, Tamil Nadu, India.
Samuel Jacob
SJ
Inbaneson
Ravikumar
R
Sundaram
Palavesam
P
Suganthi
D000962:Antimalarials / Q000494:pharmacology*; D055808:Drug Discovery; D004912:Erythrocytes / Q000187:drug effects*; D000431:Ethanol; D035264:Flowers / Q000737:chemistry; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy*; D031339:Ocimum / Q000737:chemistry*; D024301:Plant Bark / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D010963:Plasmodium falciparum / Q000187:drug effects*; D012997:Solvents
D000962:Antimalarials; D010936:Plant Extracts; D012997:Solvents; D000431:Ethanol