Ilex paraguariensis (yerba mate) an infusion herb with promising antibacterial activity and its interaction with different classes of antibiotics

Abstract

Ilex paraguariensis (Yerba Mate) is a plant found in South American countries that has known antimicrobial, anticancer, immunomodulatory and antiproliferative properties. Extensive spread of resistance has prompted the use of new antimicrobials, including natural antimicrobials found in plants. The antibacterial activity of aqueous Yerba Mate extracts on different isolates of A. baumanii and S. aureus was tested along with testing their ability to inhibit coagulase secretion in S. aureus. An aqueous extraction was first performed until dry solids were obtained. Then, the MIC was performed on the bacterial strains, which was followed by the checkerboard synergy test in order to test for any synergy that Yerba Mate might have with an antibiotic. Yerba Mate was also tested for its ability to stop coagulase secretion in S. aureus. The extracts were subjected to in vitro digestion and tested for the antibacterial activity of the different phases on different bacteria. Aqueous extracts of Yerba Mate were found to have a promising antibacterial activity on different strains of A. baumanii and S. aureus. The extracts had an additive effect with Clarithromycin, indifferent or additive effect with Cefotaxime and Ciprofloxacin and an indifferent or antagonistic effect with Gentamicin depending on the S. aureus strain tested. Mate was also able to delay coagulase secretion in S. aureus. Extracts digested in vitro still exhibited antibacterial activity on the bacterial strains tested. Further work should be done to help in the identification of the bioactive molecules in Yerba Mate.