SYNERGY OF NATURAL COMPOUNDS WITH ANTIBIOTICS IN COMBATING ANTIMICROBIAL RESISTANCE

Abstract

Objectives. The aim of this study was to evaluate the synergistic potential of natural compounds combined with conventional antibiotics, focusing on the identification of the main mechanisms involved, compounds with synergistic antimicrobial effects, and the prospects for their use as adjuncts to antimicrobial therapy.

Methods. A narrative review of the scientific literature published between 2011 and 2025 was conducted through searches of the PubMed, Scopus, and Web of Science databases. The search included terms related to natural compounds, antibiotics, antimicrobial synergy, and antimicrobial resistance. A total of 29 sources were analyzed and selected based on their relevance to the objectives of the study, with emphasis on the antimicrobial activity of natural compounds, their effects on biofilm formation, modulation of bacterial resistance mechanisms, and interactions with conventional antibiotics.

Results. The analyzed literature highlights the potential of several classes of natural compounds, including polyphenols, flavonoids, and alkaloids, to enhance antibiotic activity through multiple mechanisms. The mechanisms described include disruption of bacterial membrane integrity, inhibition of efflux pumps, suppression of biofilm formation, and modulation of enzymes involved in bacterial resistance, including β-lactamases. Epigallocatechin-3-gallate (EGCG), baicalein, and berberine have demonstrated promising synergistic effects in combination with antibiotics, particularly in experimental studies. Nanoparticles, photodynamic therapy, and controlled-release systems represent emerging technologies that may contribute to improving the bioavailability and efficacy of these compounds.

Conclusions. Certain natural compounds, including EGCG, baicalein, berberine, and curcumin, have demonstrated the potential to enhance the activity of selected antibiotics in predominantly in vitro studies through mechanisms involving disruption of the bacterial membrane, inhibition of efflux pumps, and reduction of biofilm formation. These findings support the potential use of natural compounds as adjuvants to antibiotic therapy; however, the clinical efficacy of these combinations requires validation in preclinical and clinical studies.