Antimalarial Activity of Microalgae Extracts Based on Inhibition of PfMQO, a Mitochondrial Plasmodium falciparum Enzyme

Malaria is an important global disease that threatened human life. The resistance Plasmodium sp. to the available medicines encourages the search for new antimalarial substances based on new mechanisms on the inhibition of PfMQO (the mitochondrial Plasmodium falciparum enzyme). Objective: The purposes of this study was to screen antimalarial substances from microalgae based on the inhibition of PfMQO. Materials and Methods: Five microalgae were extracted by maceration using chloroform pa and ethanol pa. These ten crude extracts obtained were tested for the inhibitory activity against the PfMQO enzyme. Results: The highest inhibitory activity against PfMQO enzyme was chloroform extract of S. costatum with 91.050% of inhibition and 0.043 μg/mL of IC₅₀. The ethanol extract of S. platensis showed 91.999% and 5.25 μg/mL of inhibition and IC₅₀, respectively. These results indicated that the two extracts provide high antimalarial activity exceeded a theoretical standard of antimalarial bioactive compounds. Conclusion: Chloroform extract of S. costatum and ethanol extract of S. platensis are promising sources of antimalarial compounds based on the inhibition of PfMQO.