Natural polyphenols as potential antibacterial agents and their delivery systems of nanosized level

Bacterial infections associated with multidrug-resistant pathogens are a serious danger to both humans and farm animals. For this reason, natural biologically active agents (BAA), in particular, polyphenols, with a wide range of biological activity could become promising molecules for effective antibacterial therapy. Despite the potentially high antibacterial activity and other beneficial biological effects, the use of such BAA is hindered due to their low water solubility. To overcome this problem, various approaches are used, for example, loading BAA into nanosized delivery systems (nanoparticles, nanocapsules, micelles, etc.). Such approaches allow not only to increase the effectiveness of natural BAA, but also to ensure their targeted (local) effect, which is important in the treatment of bacterial diseases, and in some cases result in synergic action. This review describes the antibacterial properties of the most promising polyphenols and key approaches for their delivery at the nanoscale level, as well as the methods for their development.