In vitro anthelmintic activity of Combretum molle (R. Br. ex G. Don) (Combretaceae) against Haemonchus contortus ova and larvae

Abstract

Parasitic nematodes, especially Haemonchus contortus (Rudolphi), are among the most common and economically important causes of disease in sheep and goats owned by pastoralists and small holder farmers in Africa. The control of these infections relies mainly on the use of anthelmintic drugs. However, herbal preparations are widely used by pastoralists and small holder farmers for the treatment of their livestock against helminth parasites. The anthelmintic effect of acetone leaf extract and fractions of Combretum molle was investigated to determine the relative efficacy of the components against gastrointestinal sheep nematodes. The fractions were obtained by solvent:solvent extraction from the acetone extract. These were evaluated for nematocidal activity by means of an egg hatch (EHA) and larval a development and viability assay (LDVA) in vitro. The effect of the test extracts on the hatchability of eggs and development of first to third stage larvae and the survival rate of the third stage larvae. H. contortus, were used to determine the relative bioactivities. Best-fit LC 50 values were computed using global model of nonlinear regression curve-fitting. The extracts inhibited egg hatching and development of the larvae of H. contortus in a concentration-dependent manner. Best-fit LC 50 values for the egg hatch test were 0.866, 0.333, 0.833, 0.747, and 0.065 mg/mL for acetone extract, n-butanol, hexane, chloroform, and 35% water in methanol fractions, respectively. The best-fit LC 50 values for the LDVA were 0.604, 0.362, 1.077, 0.131 and 0.318 mg/mL for the acetone extract, butanol, hexane, chloroform, and 35% water in methanol fractions, respectively. In the EHA the 35% water in methanol fraction was significantly more active than all the other fractions (p < 0.05); however the activity was not significantly different with the LDVA. C. molle leaf could find application in anthelmintic therapy in veterinary practice.

IN VITRO ANTHELMINTIC EFFECT OF <i>ANOGEISSUS LEIOCARPUS</i> (DC.) GUILL. & PERR. LEAF EXTRACTS AND FRACTIONS ON DEVELOPMENTAL STAGES OF <i>HAEMONCHUS CONTORTUS</i>

“…The more polar (butanol) and less polar (chloroform and hexane factions had lower activities. There results are more or less in the line with results found with the anthelminthic activity of Combretum molle (Ademola and Eloff, 2010). Aqueous and hydro-alcoholic extracts of Hedera helix had LC 50 of 0.12 and 0.17 mg/ml respectively when tested against H. contortus egg (Eugale et al, 2007a).…”

Phytochemical analysis and ovicidal activity of Cassia sieberiana, Guiera senegalensis and Excoecaria grahamii extracts

“…It is generally considered that the anthelminthic effects of forage containing tannins are related to their content of condensed tannins (Hoste et al, 2011). Some in vitro results suggest also that secondary metabolites such as flavonoid and alkaloïds (Molan et al, 2003;;Barrau et al, 2005;Brunet and Hoste, 2006;Eguale et al, 2008;Chagas et al, 2008;Muthee et al, 2011), saponins (Ademola and Eloff, 2010;Waterman et al, 2010) and terpenoids (Marley et al, 2006;Githiori et al, 2003) may possess some anthelminthic properties. The dosedependent relationship between the concentration of tannins and/or flavonoid compounds and the anthelminthic activity has been demonstrated under both in vitro (Molan et al, 2002;Brunet and Hoste, 2006) and in vivo conditions (Hoste et al, 2011;Brunet et al, 2007;Terrill et al, 2009).…”

&lt;i&gt;In Vitro&lt;/i&gt; Ovicidal and Larvicidal Activities of Stem Bark of &lt;i&gt;Terminalia glaucescens&lt;/i&gt; (Combretaceae) against &lt;i&gt;Haemonchus contortus&lt;/i&gt;

“…The eggs could have been inhibited by the saponins in the extract as these molecules are known to stop nematode development from egg hatching [22]. Saponins have also been reported to have nematicidal activities and are said to interact with the cell membrane causing changes in cell wall permeability [23]. They also interact with collagen proteins from the cuticle of nematodes and this interaction may be responsible for the nematotoxic effects [24].…”