In vitro evaluation of antifilarial effect of Azadirachta indica leaves extract in different solvents on the microfilariae of Setaria cervi.

Polar solvent extracts of Azadirachta indica leaves were investigated to evaluate in vitro anthelmintic activity on the microfilariae of Setaria cervi. Four extracts of A. indica leaves were prepared with different solvents in increasing order of polarity (diethyl ether < chloroform < ethanol < methanol). Stock solution of the extract of A. indica leaves was prepared in Ringer's solution at the concentrations of 50, 100 and 200 μg/ml and used against microfilariae in three replicates. Ringer's solution was used as experimental control. Mortality rates of microfilariae were recorded for each concentration after 45, 90 and 135 min, respectively. All the solvent extracts show significant anthelmintic activity at the concentration of 200 μg/ml after 135 min of incubation. Highest mortality rate of microfilariae was observed in methanol and ethanol extracts throughout the incubation period compared to chloroform and diethyl ether extracts which showed low mortality rates. Dose dependent effect of ethanol and chloroform showed highest and lowest ranking when analyzed by regression values and correlation of regression. Solvents extracts of A. indica leaves showed anthelmintic effect and therefore may be used as phytopharmacological agents in future.