Research progress of polyphenols in nanoformulations for antibacterial application

Infectious disease is one of the top 10 causes of death worldwide, especially in low-income countries. The extensive use of antibiotics has led to an increase in antibiotic resistance, which poses a critical threat to human health globally. Natural products such as polyphenolic compounds and their derivatives have been shown the positive therapeutic effects in antibacterial therapy. However, the inherent physicochemical properties of polyphenolic compounds and their derivatives limit their pharmaceutical effects, such as short half-lives, chemical instability, low bioavailability, and poor water solubility. Nanoformulations have shown promising advantages in improving antibacterial activity by controlling the release of drugs and enhancing the bioavailability of polyphenols. In this review, we listed the classification and antibacterial mechanisms of the polyphenolic compounds. More importantly, the nanoformulations for the delivery of polyphenols as the antibacterial agent were summarized, including different types of nanoparticles (NPs) such as polymer-based NPs, metal-based NPs, lipid-based NPs, and nanoscaffolds such as nanogels, nanofibers, and nanoemulsions. At the same time, we also presented the potential biological applications of the nano-system to enhance the antibacterial ability of polyphenols, aiming to provide a new therapeutic perspective for the antibiotic-free treatment of infectious diseases.