Unveiling the Molecular Profile and Antiviral Potential of Costus arabicus L. Against Zika Virus.

Widely used in Brazilian folk medicine, Costus arabicus L. (Canarana) is a herbaceous plant with promising pharmacological potential. Here, we profile the molecular composition of extracts from different plant organs and evaluate their in vitro activity against Zika virus (ZIKV). Ethanolic and aqueous extracts from leaves, stems, and roots were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) for metabolite assignment. In vitro antiviral activity was assessed against Zika, Chikungunya, and Oropouche viruses. Forty-five compounds were annotated, including amino acids, flavones, flavonols, glycosylated flavonoids, lignans, lipids, phenolic acids, steroidal saponins, and xanthones. The ethanolic extract demonstrated promising anti-ZIKV activity, with an EC₅₀ of 30.21 µg/mL and a selectivity index (SI) of 16.55. Costus arabicus L. displays a diverse molecular profile, with most compounds reported for the first time in this species and even within the genus. These findings highlight the unexplored phytochemical richness of this plant and suggest that the anti-ZIKV effect may involve synergistic interactions among flavonols, glycosylated flavonoids, lignans, and steroidal saponins.