ABSTRACT
ABSTRACT Various extracts obtained from the red alga Plocamium brasiliense (Greville Howe & Taylor), including a fraction containing crude 5-chloro-1-(E)-chlorovinyl-2,4-dibromo-1,5-dimethylcyclohexane (1) and another containing a mixture of halogenated monoterpenes (F), as well as atomaric acid meroditerpene (2) isolated from brown alga Stypopodium zonale (J. V. Lamouroux) Papenfuss, were evaluated for their activity against Trypanosoma cruzi. The cytotoxic and trypanosomicidal effects of these extracts were evaluated in Vero cells and clinically relevant forms of T. cruzi (amastigotes and trypomastigotes). All extracts from P. brasiliense presented low cytotoxicity and moderate trypanosomicidal effects, except for the hydroalcoholic extract. The crude 1 and F fractions had enhanced trypanocidal activity but showed low selectivity. Moreover, atomaric acid (2) was identified as a hit, demonstrating a potent trypanocidal effect reaching an IC50 <10 µM against two different DTU (Yand high selectivity index (<10). These results identify marine natural products as promising candidates against Chagas disease.