Neglected tropical diseases (NTDs) affect approximately 2 billion people globally and are caused by a range of pathogens, including protozoa, bacteria, and trypanosomes, primarily in tropical and subtropical regions. Among the 17 NTDs listed by the World Health Organization (WHO), protozoan infections such as those caused by Plasmodium, Entamoeba, Leishmania, and Trypanosoma represent a major public health concern. Indonesia, with its exceptional biodiversity resulting from a tropical climate, offers a wealth of plant species with promising bioactivities, making them potential sources for therapeutic development. This has led to an increased focus on exploring Indonesian plant extracts and their isolated compounds for anti-protozoal effects. A total of 48 plant extracts from the genera Cratoxylum, Diospyros, and Artocarpus were tested for antiprotozoal activity. Their effects were evaluated in vitro against Plasmodium falciparum (Pf), Entamoeba histolytica (Eh), Leishmania donovani (Ld), Trypanosoma brucei rhodesiense (Tbr), and Trypanosoma cruzi (Tc).
Dichloromethane extracts derived from Cratoxylum arborescens roots showed pronounced inhibitory activity, with IC50 values between 0.1 and 8.2 µg/mL. Cochinchinone C, a compound isolated from these extracts, displayed potent activity against Pf, Eh, Ld, Tbr, Tc trypomastigotes, and Tc epimastigotes, with IC50 values of 5.8 µM, 6.1 µM, 0.2 µM, 0.1 µM, 0.7 µM, and 0.07 µM, respectively. Remarkably, this is the first report of cochinchinone C demonstrating antiprotozoal activity. Cytotoxicity testing revealed low toxicity and high selectivity (selectivity index >10) against both cancerous and normal human cell lines, underscoring its potential as a lead compound for drug development. Cochinchinone C represents a promising candidate for antiprotozoal drug development and highlights Indonesia’s untapped potential as a source of bioactive natural products for combating neglected tropical diseases.
