TANZANIAN MEDICINAL-PLANTS USED TRADITIONALLY FOR THE TREATMENT OF MALARIA - IN-VIVO ANTIMALARIAL AND IN-VITRO CYTOTOXIC ACTIVITIES

Seventeen fractions of extracts obtained from 11 Tanzanian medicinal plants, which had previously been shown to possess a high antimalarial activity in vitro were submitted to the 4-day suppressive test in Plasmodium berghei-infected mice, and were investigated for cytotoxic activity in human carcinoma cell lines in vitro. Several fractions administered orally to the mice (500 mg/kg body weight/day) produced a significant reduction of parasitaemia. The most effective plant fractions investigated were those of the root and stem bark of Maytenus senegalensis (90% and 63% suppression of parasitaemia, respectively) and of the roots of Cissampelos mucronata (59% suppression), Highest cytotoxic activities were found with all fractions of Maytenus senegalensis (IC50<1 mu g/mL) and with the PE fraction of the roots of Salacia madagascariensis (median IC50=1.2 mu g/mL for HT 29 and 2.3 mu g/mL for KB).