Leaves, stems and whole plant of Ilex paraguariensis (yerba mate) were characterized in terms of their chemical composition and biological activities in order to determine which part of the plant is more interesting to develop bioactive formulations. The yerba mate samples contain at least five free sugars, five organic acids, eighteen fatty acids, one tocopherol, nine hydroxycinnamoyl derivatives and two flavonols. The leaves extract revealed the highest antioxidant activity, correlating with its highest levels of phenolic compounds. By contrast, the stems extract showed the highest anti-inflammatory potential and was also the most potent against MCF-7 and HepG2 cell lines, probably due to the presence of other phytochemicals. The absence of hepatotoxicity of the extracts was confirmed in porcine liver primary cells. Although the yerba mate extracts have been widely studied, this report shows for the first time the distinct potentialities of each individual part of the plant.
The authors are grateful to Foundation for Science and Technology (FTC, Portugal) for financial support to CIMO (Pest-OE/AGR/UI0690/2014), L. Barros research contract (“Compromisso para a Ciência”) and R.C. Calhelha grant (SFRH/BPD/68344/2010). R.C.G. Correa and A. H. P. Souza thank CAPES Foundation, Ministry of Education of Brazil (CAPES fellows, process numbers BEX 3974/14-6 and BEX 3972/14-03, respectively). The authors also thank to A. Fernandes for all the support in some of the laboratorial work.