Phytochemical Analysis and In-vitro Antitrypanosomal Activity of Selected Medicinal Plants in Niger State, Nigeria

Abstract

Trypanosomiasis is a disease caused by protozoan parasite belonging to the genus Trypanosoma. The disease affects both humans and animals. In this study, phytochemical analysis and in-vitro antitrypanosomal screening of crude methanol extracts of the leaves of Waltheria indica, Vernonia amygdalina, Albizia ferruginea, Camellia sinensis, Chamaecrista mimosoides and Hyptis suaveolens were carried out using standard methods. Highly parasitized blood from infected donor rats was diluted with glucose phosphate buffered saline solution and incubated with varying concentrations (1 mg/ml, 2 mg/ml and 4 mg/ml) of the extracts in Eppendorf tubes for 60 minutes. Aliquots from the mixtures were removed and observed under microscope for parasite motility at 5 minutes interval. Phytochemical screening revealed the presence of tannins, alkaloids, flavonoids,phenols and glycosides in all the plants’ extracts. Saponins were absent in H. suaveolens while steroids and phlobatannins were absence in C. mimosoides and H. suaveolens. All the plants’ extracts showed significant cessation of parasite motility with increase in incubation time and concentration of the extract. Complete cessation of the parasite motility was observed for all the extracts within 60 minutes of the study. The most active extract was W. indica at 4mg/ml which caused complete cessation of the parasite motility within 5 minutes whereas the least active plants C. mimosoides and H. suaveolens. Both caused complete cessation of the parasite motility within 25 minutes. Berenil, the standard drug, however, caused cessation of trypanosomal motility within 5 minutes even at 1 mg/ml. These results showed that methanol l extracts of the plants leaves screened especially Waltheria indica and Vernonia amygdalina have significant in vitro antitrypanosomal activity and may be potential source for the in vivo treatment of trypanosomiasis.