Preliminary studies on the anthelmintic effects of ethanolic extract of Garcinia kola (heckel) seed and methanolic extract of sacoglottis gabonensis (baillon) stem bark on Heligmosomoides bakeri larvae in Nsukka, Nigeria

Abstract

The anthelmintic activities of two folkloric medicinal plants, Garcinia kola (Heckel) seed and Sacoglottis gabonensis (Baillon) stem bark were investigated independently in in vitro studies. The effects of the crude ethanolic and methanolic extracts of the two plants, on the pre-parasitic stages of Heligmosomoides bakeri, in egg-hatch assay for Garcinia kola and larval mortality assay for both plants, were studied. Three down-graded concentrations, (100, 50 and 25 mg/ml) of Garcinia kola were used in both assays. The larval mortality assay for Sacoglottis gabonensis was carried out with the plant extract concentrations of, 125, 62.5, 31.5 and 15.625 mg/ml, and the larval counts were determined at specified time interval of 30 minutes. The concentrations, 25, 12.5 and 6.25 mg/ml of two standard anthelmintics, Albendazole and levamisole, were used in the positive control test of the egg-hatch and the larval mortality assays respectively, while of the Garcinia kola seed, 25 mg/ml of levamisole was used in the positive control test of the Sacoglottis gabonensis study. Distilled water was used in the negative control for both assays. Every test was set up in triplicate. By using the number of eggs that hatched in distilled water as the standard, the number of eggs that hatched in each concentration of the plants extracts and the drugs was expressed as a percentage reduction in egg-hatch. The same procedure was used to obtain the percentage paralysis of the larvae in the larval mortality assay. Garcinia kola seed extract inhibited only 18.75% of the egg-hatch at the maximum concentration used but irreversibly paralyzed 76.52% of the larvae at 50 mg/ml. This compares with the efficacy of levamisole at 12.5
mg/ml; (p > 0.05).The maximum and minimum concentrations of Sacoglottis gabonensis achieved 100 % irreversible larval paralysis, compatible with the 25 mg/ml of levamisole, in 30 and 150 minutes respectively. Both plant extracts were found to posses some anthelmintic activities in vitro that could further be exploited.

KEY WORDS: Garcinia kola, Sacoglottis gabonensis , Anthelmintic, in vitro