Natural Compounds of Plant Origin–Promising Agents in the Fight Against Antibiotic Resistance

Antimicrobial resistance (AMR), or antibiotic resistance of microorganisms, is becoming a global threat to healthcare, and strains with multidrug resistance (MDR) pose significant challenges for drug development programs. New mechanisms of antimicrobial traits render existing drugs ineffective, leading to prolonged illnesses and increased costs. The misuse of traditional and widely available antibiotics in healthcare, hygiene, veterinary medicine and agriculture is the main reason for the evolution, maintenance and alarming rate of spread of antimicrobial resistance. The continuing decline in antibiotic efficacy exacerbates the situation, necessitating urgent efforts by the global community aimed at developing innovative antibacterial drugs and treatments for infections caused by MDR pathogens. In addition to various natural and synthetic agents currently undergoing preclinical and clinical testing, secondary plant metabolites, or phytochemicals, are proving effective in combating drug-resistant strains. Various phytochemicals from classes such as alkaloids, phenolic derivatives, terpenoids, coumarins, organosulfur compounds and polypeptides have successfully demonstrated their antibacterial potential against MDR pathogens. Phytochemicals have been shown to be effective against molecular factors such as membranes, proteins, biofilms, efflux pumps and bacterial cell communication. However, despite promising results, further in-depth studies are needed to implement these approaches in clinical practice. The review examines successful examples, current challenges and prospects for the further application of phytochemicals in combating antimicrobial resistance of microbial pathogens.