The
in vitro antitrypanosomal activity of
Citrullus lanatus
leaf aqueous extract and its effects on blood parameters of
Trypanosoma brucei
infected albino rats was investigated in this study. The plant extract showed
in vitro activity against
T. brucei at a minimum concentration of 0.0875 mg/ml. There was a positive correlation between extract concentration and parasitaemia clearance, with administration of the extract at 10 mg/ml concentration resulting in zero parasitaemia count. Thirty albino rats divided into six groups (A-F) of five rats each were used for the haematological study. Graded extract doses of 200, 400 and 600 mg/kg were administered orally to groups A, B, and C respectively following an establishment of parasitaemia of 4 × 10
6 two days post infection. Group D (Veriben®−treated) was given a single dose of 3.5 mg/kg diminazine aceturate (Veriben®) intramuscularly. Group E (Untreated) was not treated with any trypanocide but given 10 ml/kg of distilled water orally, while group F (Uninfected) were not infected with the parasites and did not receive any treatments. There was a significant (p<0.0001) decrease in mean packed cell volume (PCV) and red blood cell (RBC) counts of the infected and untreated group (E), when compared with the uninfected (F), and the infected but treated groups (A-D). The mean haemoglobin concentration was significantly (p<0.0001) higher in untreated uninfected and Veriben®−treated albino rats compared with those treated with the extracts (A−C) and the untreated infected rats (E). White blood cell (WBC) counts increased significantly (p<0.0001) in the untreated infected group (E) compared with the uninfected (F), extract-treated (A−C) and Veriben®−treated (D) groups. In conclusion, our investigation shows that the aqueous extract of
C. lanatus leaf is toxic to
T. brucei in vitro. However,
in vivo studies are needed to demonstrate that it has any beneficial value in clearing parasites from infected animals.