Larvicidal activity of Artemisia annua L. callus culture against Anopheles stephensi larvae.

The emergence of resistance by both Plasmodium falciparum and Anopheles stephensi made the search for an alternative environmentally safe plant based insecticide inevitable. Artemisia annua is a well known antimalarial. Present study is an attempt to induce callus production from young leaves of Artemisia annua plant and study its larvicidal activity against larvae of Anopheles stephensi. Callus was initiated by using different concentrations of auxins and cytokinins. A suitable culture media was standardized for optimal growth of callus. Healthy callus cultures were obtained in the slightly modified Murashige and Skoog's medium +NAA and BAP (0.03 and 0.2 mg l(-1) respectively) + Sucrose 20 gm l(-1) +Agar 8 gm l(-1) within 28 days of inoculation. Callus was successively extracted in order of increasing polarity of solvents. Larvicidal activity, in terms of lethal concentration (LC50) of the callus extract in chloroform was calculated to be 18.45 +/- 0.75 ppm after72 hr against third instar larvae of A. stephensi.

Toxicity of artemisinin [Artemisia annua L.] in two different periods of pregnancy in Wistar rats.

Artemisinin compounds are important for treating multidrug-resistant malaria; however, the possible resorption and abnormalities observed in animal reproduction studies may contraindicate artemisinin use during the first trimester. To evaluate whether artemisinin interferes with developmental outcomes at different periods of pregnancy, Wistar rats were treated by gavage with increasing doses of 7, 35 and 70 mg/kg/day from gestational day [GD] 7 to 13 or 14 to 20. Viable embryos and post-implantation losses, and progestagens and testosterone levels, were monitored in the former treatment group and pregnancy and outcomes data, post-implantation losses and male and female developmental endpoints of the offspring were evaluated in the latter treatment group. Results indicate toxicity for both periods of treatment, with lower sensitivity at later stages of pregnancy. The results showed that dosing with 35 or 75 mg/kg of artemisinin caused high percentages of post-implantation losses that correlated with a trend to lower maternal progestagens and a significant maternal testosterone decrease. These findings demonstrate that oral administration of artemisinin can adversely effect post-implantation development and pregnancy in the rat.