Anthelmintic activity of Acacia oxyphylla stem bark against Ascaridia galli
Abstract
The anthelmintic activity of the ethanol extract of Acacia oxyphylla Graham ex Bentham (Mimosaceae) stem bark was tested against Ascaridia galli Schrank (Nematoda), the intestinal roundworm of domestic fowl. Different concentrations of the extract (0.5, 1, 2, 5, 10 and 20 mg/mL) were prepared in 0.9% phosphate buffered saline (PBS) with 1% dimethylsulfoxide (DMSO). In vitro treatment of the adult roundworms indicated concentration-dependent efficacy of the plant extract. Similar concentrations of a broad-spectrum antiparasitic drug, albendazole, were used as a standard reference. Control experiments consisted of nematodes maintained in 0.9% PBS with 1% DMSO. Albendazole was significantly effective ( P < 0.05) at all concentrations tested in causing mortality of A. galli. However, the plant extract showed concentration-dependent efficacy only at the concentrations of 2, 5, 10, and 20 mg/mL. In order to ascertain the anthelmintic effect, scanning electron microscopy was performed, which indicated devastating structural alterations on the fine topography of A. galli treated with 20 mg/mL of the plant extract, when compared with that of the control specimen. Severe shrinkage of the cuticle, loosening and collapse of the lips, and extensive irregular wrinkles all over the body surface were very distinct on the plant extract-treated nematode. Moreover, high magnification of the cuticle revealed formation of a number of small swellings or blebs, which apparently marked the initiation of disintegration of the entire cuticle.