Oxidative Stress Modulation and Antileishmanial Activity of Salvinia auriculata

The genus Salvinia has gained attention for its phytoremediation capacity and high levels of bioactive secondary metabolites, positioning it as a potential source of novel therapeutics. Considering the global burden of leishmaniasis and the central role of oxidative stress in disease, this study investigated the antioxidant and antileishmanial properties of the ethanolic extract of Salvinia auriculata. Salviniside II, the major metabolite, was isolated, structurally characterized, and quantified. Antioxidant capacity was assessed using in vitro chemical assays (DPPH, ABTS, and FRAP), an ex vivo human erythrocyte model, and in vivo Caenorhabditis elegans under juglone-induced oxidative stress. Antileishmanial activity of the extract and salviniside II was evaluated against Leishmania amazonensis and Leishmania infantum. The extract showed notable antioxidant and antiparasitic effects, whereas salviniside II alone was less effective at inhibiting parasite growth, suggesting contributions from other compounds or synergistic interactions within the extract. These findings underscore the remarkable accumulation of an underexplored metabolite, salviniside II, in S. auriculata and highlight the dual antioxidant and antileishmanial potential of its ethanolic extract. Thus, S. auriculata emerges as a promising candidate for developing new therapies targeting oxidative stress-related conditions and neglected tropical diseases, including leishmaniasis.