Antimalarial activity of Bidens pilosa L. (Asteraceae) ethanol extracts from wild plants collected in various localities or plants cultivated in humus soil.
Bidens pilosa (Asteraceae), a medicinal plant used worldwide, has antimalarial activity as shown in previous work. This study tested ethanol extracts from wild plants collected in three different regions of Brazil and from plants cultivated in various soil conditions. The extracts were active in mice infected with P. berghei: doses of < or =500 mg/kg administered by oral route reduced malaria parasitaemia and mouse mortality; higher doses were found to be less effective. Tested in vitro against three P. falciparum isolates, two chloroquine resistant and one mefloquine resistant, the plants cultivated under standard conditions, and in humus enriched soil, were active; but the wild plants were the most active. Analysis using thin layer chromatography demonstrated the presence of flavonoids (compounds considered responsible for the antimalarial activity) in all plants tested, even though at different profiles. Because B. pilosa is proven to be active against P. falciparum drug-resistant parasites in vitro, and in rodent malaria in vivo, it is a good candidate for pre-clinical tests as a phytotherapeutic agent or for chemical isolation of the active compounds with the aim of finding new antimalarial drugs.
Laboratory of Malaria, Centro de Pesquisas René Rachou/FIOCRUZ, Av. Augusto de Lima 1715, Belo Horizonte, Minas Gerais CEP 30190-002, Brazil.
Valter F
VF
Andrade-Neto
Maria G L
MG
Brandão
Francielda Q
FQ
Oliveira
Vicente W D
VW
Casali
Brian
B
Njaine
Mariano G
MG
Zalis
Luciana A
LA
Oliveira
Antoniana U
AU
Krettli
D000818:Animals; D000962:Antimalarials / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D031176:Bidens; D004351:Drug Resistance; D016778:Malaria, Falciparum / Q000517:prevention & control*; D051379:Mice; D021261:Parasitic Sensitivity Tests; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018517:Plant Roots; D010962:Plasmodium berghei / Q000187:drug effects*; D010963:Plasmodium falciparum / Q000187:drug effects*; D012987:Soil
D000962:Antimalarials; D010936:Plant Extracts; D012987:Soil