In vivo antimalarial activity of leaves of Plectranthus amboinicus (lour) spreng on Plasmodium berghei yoelii.

An invivo study of aqueous extract of the leaves of Plectranthus amboinicus on Plasmodium berghei yoelii was conducted on laboratory infected albino mice and compared with standard drug chloroquine. Reduction of parasitemia at 250 mg/kg and 500 mg/kg of aqueous extract for 24 hrs, 48 hrs, 72 hrs and 96 hrs were determined. The reduction of parasitemia after 96 hrs was 100%, 67.9% and 76.2% for standard, 250 mg/kg and 500 mg/kg of aqueous extract respectively. The isolation of active principle responsible for the reduction of parasitemia may give a promising drug molecule.

Mosquito larvicidal properties of various extract of leaves and fixed oil from the seeds of Caesalpinia bonduc (L) Roxb.

A Preliminary laboratory trial was undertaken to determine the efficacies of petroleum ether, ethanolic, aqueous extracts of dried leaves and fixed oil from the seeds of Caesalpinia bonduc (L). Roxb (Family: Caesalpiniaceae) at various concentrations against the fourth instar larvae of Culex quinquefasciatus by following the WHO guidelines. Hundred per cent mortality was observed in 1% concentration of petroleum ether and ethanolic extract of leaf, whereas it was 55% in 2.5% concentration of aqueous extract and 92.6% in 2.5% concentration of fixed oil. The active constituent responsible for the mortality is to be isolated to come up with a promising larvicidal agent, which will be economic, non pollutant and ecofriendly.