Abstract:
Background: The emergence of drug resistance to P. falciparum becomes challenging. Thus, a continued search for other effective, safe and cheap plant-based antimalarial agents becomes imperative in the face of these difficulties.
Objective: This study was aimed to investigate the antimalarial potentials of the crude stem bark extract and solvent fractions of P. linearifolia in Plasmodium berghei infected mice.
Methods: The dried stem bark of P. linearifolia was pulverized and extracted with 80% methanol. The dried crude extract was then further fractionated with n-hexane, chloroform, and ethyl acetate. For suppressive test, after three hours post inoculation of P. berghei, the first group was administered the vehicle 10 ml/kg. The second group was given chloroquine 25 mg/kg. Whereas the remaining three groups were administered 200, 400 and 600 mg/kg of the crude extract and 100,200 and 400 mg/kg of each of the chloroform, ethyl acetate and aqueous fractions. Furthermore, the crude extract and the aqueous fraction were evaluated using Rane’s model for the curative test. The result was statistically analyzed using paired T-test and one-way analysis of variance (ANOVA). The results were considered significant at P < 0.05.
Result: In the suppressive test, the crude extract and fractions suppressed parasitemia level significantly (P<0.05 for 200 and 400 mg/kg, P<0.001 for 600 mg/kg of the crude extract; P<0.01 for 100 mg/kg, P<0.001 for 200 and 400 mg/kg of the aqueous and P<0.01 for 200 mg/kg, P<0.001 for 400 mg/kg of chloroform fractions). Whereas, in curative model 400 mg/kg of the aqueous fraction (P<0.01) and 600 mg/kg of the crude extract (P<0.001) showed a significant parasitemia level reduction. Both 400 and 600 mg/kg of the crude extract and 400 mg/kg of aqueous and chloroform fractions reversed reduction in packed cell volume.
Conclusion: The results indicated that the plant is nontoxic at 2gm/kg and has a promising antiplasmodial activity against Plasmodium berghei, which upholds the earlier in vitro findings. Thus, it could be considered as a potential source to develop new antimalarial agents.
