In vitro anthelmintic activity of Azadirachta indica and Morinda lucida leaf extracts against adult Haemonchus placei

Abstract

Plants with anthelmintic activity have attracted considerable interest for their potential to treat helminthiasis, a major cause of reduced livestock production and profitability. In this study, we evaluated leaf extracts of Morinda lucida and Azadirachta indica for anthelmintic activity against Haemonchus placei, a blood-feeding nematode. Dried leaves of the plants were powdered and successively extracted with chloroform and acetone. After concentration and drying, the extracts were analysed by thin-layer chromatography to obtain chromatogram fingerprints, and then evaluated for activity against H. placei by exposing adult worms to varying extract concentrations for 3 hours. Percent lethality was determined from the number of dead worms. Data were fitted to a non-linear regression equation (log concentration of extract vs % lethality; variable slope) to produce best-fit sigmoidal curves, and LC50 values were computed. Extraction yields (% w/w) and anthelmintic potency parameters (mg/mL) were: chloroform extracts - M. lucida 3.2, 66.57; A. indica 5.1, 64.08; and acetone extracts - M. lucida 0.9, 12.52; A. indica 0.5, 43.58. Fingerprints revealed secondary metabolite patterns that provided characteristic visual impressions of the extracts. Of the four extracts investigated, the most active was the acetone extract of M. lucida, which could be useful as an anthelmintic phytomedicine.