Antiplasmodial Activity of the Root Extracts of Cochlospermum tinctorium in Mice Experimentally Infected with Clinical Isolates of Plasmodium berghei berghei (NK 65)

摘要

Aims: To determine in vivo the antiplasmodial activity of two chromatographic fractions obtained from Cochlospermum tinctorium A. Rich root bark extract against Plasmodium berghei berghei in mice. Methodology: Two chromatographic fractions were obtained from the crude methanolic extract of C. tinctorium root bark using petroleum ether (Fraction 1) and ethanol (Fraction 2) which were tested to determine their antiplasmodial activity in Swiss Albino mice infected with P. berghei berghei. Fraction 1 was administered at dose levels of 50, 100 and 200mg/kg/day, while fraction 2 was administered at dose levels of 25, 50 and 100 mg/kg/day. Chloroquine at 5 mg/kg per day was used as positive control and 0.2 ml normal saline was applied per day as sham. Results: Fraction 1had a percentage antiplasmodial activity of 80.67%, 64.14% and 69.71% for the dose level of 50, 100 and 200 mg/kg respectively. Data shows that fraction 1 treatment was not dose dependent as the lowest dosage of 50 mg/kg/day produced the highest percentage antiplasmodial activity of 80.67%, while 5 mg/kg chloroquine gave 100% cure. The effects of all treatments were significantly different (p0.05) from that of 5 mg/kg chloroquine. The Median survival time post infection for infected mice treated with sham was 11 days, for infected mice treated with 50, 100 and 200mg/kg of fraction 1, the median survival time was 15.5, 15.5 and 19 days respectively, the log-rank (Mantle-Cox) test value of p0.05).There was however no significant difference (p>0.05) in the mean percentage antiplasmodial activity of fraction 2 (65.26%) which was higher than that of fraction 1 (62.90%). Conclusion: C. tinctorium root bark extractpossess antimalarial and anaemia ameliorating properties which validates its use in traditional medicine for the treatment of malaria.