Abstract:

In quest of a new trypanocidal compounds from medicinal plants, methanolic extracts of Quercus borealis leaves and Zingiber officinale roots at concentrations (250-1000 µg/ml) were screened for their anti trypanosomal activity against Trypanosoma evansi maintained in vitro in culture medium seeded with Vero cells. In vitro cytotoxicity of the chloroform extract at concentrations (100-1.56 µg/ml) was carried out on Vero cells grown in Dulbecco’s Modified Eagle Medium (DMEM) at appropriate conditions. Anti trypanosomal activity of methanolic plant extracts (MPES) varied from immobilization (clumped trypanosomes in the bottom of the wells) to the killing of the trypanosomes depending on the extract concentrations and time of exposure. MPE of Quercus borealis exhibited a significant trypanocidal activity by reduction of average mean trypanosomes counts from initial concentration (40.00±0.00) at 250 µg/ml and complete killing of trypanosomes at 9 h of incubation at the same concentration. While, MPE of Z. officnale had a reduction of average mean trypanosomes counts from 40.00±0.00 to 0.58±0.02 at all concentrations. Both MPE of Q. borealis and Z. officinale and diminazine aceturate were cytotoxic to the Vero cells in al concentrations except at 1.56, 6.25-1,56 and 6.25-1.56µg/ml, respectively.

Keywords: Medicinal Plants, Quercus borealis leaves, Zingiber officinale roots, Trypanosomaevansi, Trypanocidal activity, in vitro cytotoxicity test