The anthelmintic effect of aqueous methanol extract of Combretum molle (R. Br. x. G. Don) (Combretaceae) in lambs experimentally infected with Haemonchus contortus.

The aqueous methanol extract from the stem-bark of Combretum molle was evaluated for anthelmintic activity in lambs infected with Haemonchus contortus using faecal egg count (FEC) reduction assay. The extract showed a dose-dependent reduction in FEC in infected animals. At doses of 500, 1000 and 2000 mg kg(-1), the extract caused FEC reduction of 63%, 69.25% and 96.23%, respectively. Similarly, the standard anthelmintic (albendazole) at a dose of 200 mg kg(-1) produced FEC reduction of 99.24%. FEC reduction produced by the extract at doses of 500 and 1000 mg kg(-1) is below the minimum standard of 90% FEC recommended by the World Association for the Advancement of Veterinary Parasitology (WAAVP). However, there was no significant (P>0.05) difference between the means of groups treated with 1000 mg kg(-1) and 2000 mg kg(-1) compared to that of albendazole. In this study, C. molle has shown a promising anthelmintic activity against experimental haemonchosis. Nonetheless, further studies to evaluate its detailed toxicity are required for the plant extract to be developed into a useful anthelmintic drug. There is also the need to evaluate other parts of the plant (root, leaves, fruits, etc.) for the same effect.

Evaluation of selected South African plant species for antioxidant, antiplatelet, and cytotoxic activity.

The antioxidant, antiplatelet, and cytoxoxic effects of seven South African plant extracts, namely, Combretum vendae A.E. van Wyk (Combretaceae), Commiphora harveyi (Engl.) Engl. (Burseraceae), Khaya anthotheca (Welm.) C.DC (Meliaceae), Kirkia wilmsii Engl. (Kirkiaceae), Loxostylis alata A. Spreng. ex Rchb. (Anacardiaceae), Ochna natalitia (Meisn.) Walp. (Ochnaceae), and Protorhus longifolia (Bernh. Ex C. Krauss) Engl. (Anacardiaceae), were evaluated using established in vitro assays. All the extracts showed comparably low toxicity except for the extract of C. harveyi that showed high hemagluttination assay titer value, which indicates toxicity. The extracts of P. longifolia, K. wilmsii, O. natalitia, L. alata, C. harveyi, and C. vendae exhibited antioxidant properties in the qualitative assay using DPPH. In the quantification of antioxidation using ABTS, only the extracts of P. longifolia, L. alata, and C. vendae showed antioxidant activity with respective TEAC values of 1.39, 1.94, and 2.08. Similarly, in the quantitative DPPH assay, L. alata (EC50, 3.58+/-0.23 microg/mL) and K. wilmsii (EC50, 3.57+/-0.41 microg/mL) did not differ significantly (p

Can MTT be used to quantify the antioxidant activity of plant extracts?

Antioxidant properties of three different medicinal plant extracts from northern Nigeria were evaluated using the traditional qualitative 2,2, diphenyl-picrylhydrazyl (DPPH) method and a new 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) microdilution method described here. The results were in agreement. It is a simple, rapid and inexpensive method compared with many other methods for determining quantitative antioxidant activity of plant extracts.

Antidiarrhoeal activity of the methanol stem-bark extract of Annona senegalensis Pers. (Annonaceae).

AIM OF THE STUDY: To investigate the antidiarrhoeal properties of the stem-bark extract of Annona senegalensis, using both in vivo and in vitro models. MATERIALS AND METHODS: Swiss albino mice were used to investigate the acute oral toxicity of the extract. The extract was administered orally to mice fed with charcoal meal in order to investigate intestinal transit time. The effect of the extract on contraction of isolated rabbit jejunum and the responses of the tissue to acetylcholine and histamine were also investigated. RESULTS: The extract was safe at doses up to 5000 mg/kg. The extract at the dose of 10mg/kg significantly (p<0.05) decreased intestinal transit time at concentrations of 0.2-3.2 mg/ml, the extract attenuated spontaneous contractions of the isolated rabbit jejunum, and those induced by acetylcholine in a concentration-dependent fashion. CONCLUSION: The extract decreased intestinal transit time by attenuating the spontaneous contractions of the intestine, thus the study provided a scientific basis for the use of Annona senegalensis stem bark extract in the treatment of diarrhoea.