title: In vitro studies on the sensitivity pattern of Plasmodium falciparum to anti-malarial drugs and local herbal extracts.
abstract: BACKGROUND
  The resistance of human malaria parasites to anti-malarial compounds has become considerable concern, particularly in view of the shortage of novel classes of anti-malarial drugs. One way to prevent resistance is by using new compounds that are not based on existing synthetic antimicrobial agents.
  
  
  RESULTS
  Sensitivity of 100 Plasmodium falciparum isolates to chloroquine, quinine, amodiaquine, mefloquine, sulphadoxine/pyrimethamine, artemisinin, Momordica charantia ('Ejirin') Diospyros monbuttensis ('Egun eja') and Morinda lucida ('Oruwo') was determined using the in vitro microtest (Mark III) technique to determine the IC50 of the drugs. All the isolates tested were sensitive to quinine, mefloquine and artesunate. Fifty-one percent of the isolates were resistant to chloroquine, 13% to amodiaquine and 5% to sulphadoxine/pyrimethamine. Highest resistance to chloroquine (68.9%) was recorded among isolates from Yewa zone while highest resistance to amodiaquine (30%) was observed in Ijebu zone. Highest resistance to sulphadoxine/pyrimethamine was recorded in Yewa and Egba zones, respectively. A positive correlation was observed between the responses to artemisinin and mefloquine (P<0.05), artemisinin and quinine (P<0.05) and quinine and mefloquine (P<0.05). A negative correlation was observed between the responses to chloroquine and mefloquine (P>0.05). Highest anti-plasmodial activity was obtained with the ethanolic extract of D. monbuttensis (IC50 = 3.2 nM) while the lowest was obtained from M. lucida (IC50 = 25 nM).
  
  
  CONCLUSIONS
  Natural products isolated from plants used in traditional medicine, which have potent anti-plasmodial action in vitro, represent potential sources of new anti-malarial drugs.
authors.affiliation: Department of Biological Sciences, Covenant University, Ota, Ogun State, Nigeria. grace.olasehinde@covenantuniversity.edu.ng.
authors.forename: Grace I
authors.initials: GI
authors.lastname: Olasehinde
authors.forename: Olusola
authors.initials: O
authors.lastname: Ojurongbe
authors.forename: Adegboyega O
authors.initials: AO
authors.lastname: Adeyeba
authors.forename: Obasola E
authors.initials: OE
authors.lastname: Fagade
authors.forename: Neena
authors.initials: N
authors.lastname: Valecha
authors.forename: Isaac O
authors.initials: IO
authors.lastname: Ayanda
authors.forename: Adesola A
authors.initials: AA
authors.lastname: Ajayi
authors.forename: Louis O
authors.initials: LO
authors.lastname: Egwari
mesh_terms: D000293:Adolescent; D000328:Adult; D000962:Antimalarials / Q000008:administration & dosage / Q000494:pharmacology*; D029788:Diospyros / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D029777:Momordica charantia / Q000737:chemistry*; D032066:Morinda / Q000737:chemistry*; D009549:Nigeria; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D010963:Plasmodium falciparum / Q000187:drug effects*; D055815:Young Adult
chemical_list: D000962:Antimalarials; D010936:Plant Extracts