title: In vitro and in vivo antimalarial studies of Striga hermonthica and Tapinanthus sessilifolius extracts.
abstract: The antimalarial activities of the methanol extracts of Striga hermonthica (whole plant) and Tapinanthus sessilifolius (leaves), commonly used in Northern Nigeria for the treatment of malaria, were evaluated. In the in vitro antiplasmodial analysis, the extracts of T. sessilifolius and S. hermonthica utilized in the study, displayed mild to weak activities with IC50 values of 200.5 and 274.8 microg/ml respectively. This was investigated, using the multidrug resistant Plasmodium falciparum, K1 strain, in the parasite lactate dehydrogenase assay. The murine model in vivo antimalarial activity of the tested extracts, using chloroquine-sensitive Plasmodium berghei (ANKA P1), in the 4-day suppressive test, showed that both plants had intrinsic antimalarial properties, that were dose-dependent. At a dose of 400mg/kg weight of mice, extract of S. hermonthica exhibited a higher intrinsic antimalarial activity (68.5 % suppression) than that of T. sessilifolius (51.3 %). Chloroquine, the standard reference drug, had an average suppression of 78.0 % at a dose of 10 mg/kg weight of mice while normal saline was used as control. Preliminary phytochemical screening of the extracts indicated the presence ofsaponins, tannins, flavonoids, volatile oils and cardiac glycosides.
authors.affiliation: Department of Medicinal Chemistry and Quality Control, National Institute for Pharmaceutical Research and Development, P.M.B 21, Abuja, Nigeria.
authors.forename: L C
authors.initials: LC
authors.lastname: Okpako
authors.forename: E O
authors.initials: EO
authors.lastname: Ajaiyeoba
mesh_terms: D000818:Animals; D000962:Antimalarials / Q000627:therapeutic use; D002738:Chloroquine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D028183:Loranthaceae; D016778:Malaria, Falciparum / Q000188:drug therapy*; D008297:Male; D051379:Mice; D010936:Plant Extracts / Q000627:therapeutic use*; D018515:Plant Leaves; D010963:Plasmodium falciparum / Q000187:drug effects; D034362:Striga
chemical_list: D000962:Antimalarials; D010936:Plant Extracts; C023676:chloroquine diphosphate; D002738:Chloroquine; D007770:L-Lactate Dehydrogenase