**1. Introduction**

The latest food consumer trends point beyond fulfilling the function of providing nutrients to the body. It is intended that foods provide compounds capable of reducing the likelihood of developing diseases, improving or complementing the functions of the body, and even increasing life expectancy. A search for new food sources of these "healthy compounds" is

© 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2017 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

underway to meet the needs of today's consumers. New analytical methods are being used with known foods to demonstrate properties they always had, but properties that had not been properly tested because of technological limitations; new foods or derived food compounds are also being found.

The diversity of food we know is derived from the biodiversity of plant and animal species we know. However, there are still many plant species which have not been explored or whose potential is just beginning to come to light. Many of these plants have been used by aboriginal groups around the world since ancient times. These species, which only grow in specific geographic locations (endemism), are rarely objects of scientific study or for industrial or commercial scaling.

Chile is one of the top five hotspots of plant biodiversity on the planet; here it is possible to find new food and food-derived resources of interesting compounds in the poorly explored flora. In addition, the biodiversity of plant species found in Chile have a high degree of endemism, indicating that they do not grow elsewhere. Leaves, stems, roots, or fruits can be sources of antioxidants and/or antibacterial compounds. Among the plant species with potential are the non-fruiting tree specimens such as quillay and ulmo; within fruit tree species, we may find maqui, murta, calafate, and others that are less known. All these products have high contents of polyphenolics, which have high antioxidant and antibacterial properties.

Polyphenolics are secondary metabolites from plants that have been associated with several healthy benefits such as the prevention of cancer, cardiovascular, inflammatory, and neurodegenerative diseases [1–3]; they are also associated with bioactive properties such as antioxidant and antibacterial properties [4–7].

Each phenolic/flavonoid compound has different antioxidant/antibacterial potency depending on its action mechanism. Phenolic compounds alter the permeability of bacterial cell membranes, which may result in the uncoupling of oxidative phosphorylation, the inhibition of active transport, and the loss of pool metabolites due to cytoplasmic membrane damage [8, 9]. Other authors explain the antibacterial activity of phenolics by the presence of more number of hydroxyl groups that may form hydrogen bonds with enzymes, altering their metabolism and also the lipid solubility and the degree of steric hindrance [10, 11]. In the case of flavonoids, antibacterial activity has been associated with its capacity to form complex bonds with proteins through non-specific forces such as hydrogen bonding and hydrophobic effects, as well as by covalent bond formation. Thus, it may inactivate microbial adhesins, enzymes, and cell envelope transport proteins. Lipophilic flavonoids may also disrupt microbial membranes [12, 13].
