Chemical Composition and In Vitro Antiplasmodial Activity of the Ethanolic Extract of Cyperus articulatus var. nodosus Residue.

Cyperus articulatus L. is popularly known as priprioca. Its rhizomes are used as a medicine in the treatment of malaria in traditional medicine. Since priprioca oil is extracted for commercial purpose, we evaluated if the components from the priprioca residue can be a source of antiplasmodial active molecules. This study aimed to determine the in vitro antiplasmodial and cytotoxicity activities of the ethanolic extract of C. articulatus as an in vitro antiplasmodial agent. From the solid residue of the plant rhizomes, 40 g samples were removed and subjected to hot extraction using a Soxhlet extractor. The in vitro antiplasmodial activity was determined using the W2 and 3D7 strains of P. falciparum. The phytochemical study identified the following main compounds: corymbolone (14.25%), cyclocolorenone (9.75%), and cadalene (8.36%). The extract exhibited moderate IC50 (inhibitory concentration) against the two strains of P. falciparum: 1.21 ± 0.01 against the W2 strain and 1.10 ± 0.06 µg/mL against the 3D7 strain. Our results show the therapeutic potential of priprioca residue as a low-cost antiplasmodial agent.

In vitro and in vivo antimalarial activity of the volatile oil of Cyperus articulatus (Cyperaceae)

Malaria is a disease of global tropical distribution, being endemic in more than 90 countries and responsible for about 212 million cases worldwide in 2016. To date, the strategies used to eradicate this disease have been ineffective, without specific preventive measures such as vaccines. Currently, the existing therapeutic arsenal is limited and has become ineffective against the expansion of artemisinin-resistant Plasmodium, demonstrating the need for studies that would allow the development of new compounds against this disease. In this context, we studied the volatile oil obtained from rhizomes of Cyperus articulatus (VOCA), a plant species commonly found in the Amazon region and popularly used as a therapeutic alternative for the treatment of malaria, in order to confirm its potential as an antimalarial agent by in vitro and in vivo assays. We cultured Plasmodium falciparum W2 (chloroquine-resistant) and 3D7 (chloroquine-sensitive) strains in erythrocytes and exposed them to VOCA at different concentrations in 96-well microplates. In vivo antimalarial activity was tested in BALB/c mice inoculated with approximately 106 erythrocytes infected with Plasmodium berghei. VOCA showed a high antimalarial potential against the two P. falciparum strains, with IC50 = 1.21 µg mL-1 for W2 and 2.30 µg mL-1 for 3D7. VOCA also significantly reduced the parasitemia and anemia induced by P. berghei in mice. Our results confirmed the antimalarial potential of the volatile oil of Cyperus articulatus. (AU)