In the search for antiprotozoal compounds from natural sources, Triclisia patens displayed activity against L. donovani promastigotes (IC(50) = 1.5 microg/mL) and T. b. brucei blood stream trypomastigote forms (IC(50) = 31.25 microg/mL). In addition, a total of 20 bisbenzylisoquinoline alkaloids were screened for antileishmanial and antitrypanosomal activity in vitro. Fangchinoline (IC(50) = 0.39 microM) was found to be as active as the standard pentamidine against Leishmania donovani promastigotes. Phaeanthine was three-fold more active (IC(50) = 2.41 microM; 1.5 microg/mL) than the standard drug Pentostam against L. donovani amastigotes, but at this concentration was toxic to murine macrophages. In contrast, cocsoline (IC(50) = 12.3 microM; 6.76 microg/mL) was as active as Pentostam, and was not toxic to macrophages at this concentration. Thalisopidine showed the strongest activity (IC(50) = 1.14 microM) against Trypanosoma brucei brucei blood stream form trypomastigotes, but was less active than pentamidine.
Copyright 2002 John Wiley & Sons, Ltd.