Antimicrobial Activity of Yerba Mate (Ilex paraguariensis) Aqueous Extracts against Escherichia coli O157:H7 and Staphylococcus aureus
Article first published online: 5 JUL 2011
© 2011 Institute of Food Technologists®
Journal of Food Science
Volume 76, Issue 6, pages M456–M462, August 2011
How to Cite
Burris, K. P., Davidson, P. M., Stewart, Jr, C. N. and Harte, F. M. (2011), Antimicrobial Activity of Yerba Mate (Ilex paraguariensis) Aqueous Extracts against Escherichia coli O157:H7 and Staphylococcus aureus. Journal of Food Science, 76: M456–M462. doi: 10.1111/j.1750-3841.2011.02255.x
- Issue published online: 5 AUG 2011
- Article first published online: 5 JUL 2011
- MS 20110227 Submitted 2/23/2011, Accepted 5/1/2011.
- antimicrobial activity;
- aqueous tea extract;
- foodborne pathogens;
- Ilex paraguariensis;
- Yerba Mate
Abstract: Bioactive compounds from natural plant sources are becoming increasingly important to the food industry. Ilex paraguariensis is used in the preparation of a widely popular tea beverage (Yerba Mate) in the countries of Uruguay, Paraguay, Argentina, and Brazil. In this study, extracts of 4 brands of commercial tea, derived from the holly plant species, Ilex paraguariensis, were evaluated for their ability to inhibit or inactivate bacterial foodborne pathogens. The ultimate goal was to evaluate potential use of the extracts in commercial applications. Dialyzed aqueous extracts were screened for antimicrobial activity against Escherichia coli O157:H7 and Staphylococcus aureus. S. aureus was found to be the more sensitive to extracts than E. coli O157:H7. Minimum bactericidal concentrations (MBCs) were determined to be approximately 150 to 800 μg/mL and 25 to 50 μg/mL against E. coli O157:H7 and S. aureus, respectively. A Uruguayan brand had reduced activity against E. coli O157:H7 compared to the Argentinean brands tested. It was concluded that Yerba Mate could be used as a potential antimicrobial in foods and beverages against these pathogenic bacteria.
Practical Application: Soluble extracts from Yerba Mate are natural antimicrobials that can be incorporated into food products to achieve longer shelf life.