Antimicrobial and antibiofilm actions of iridoids: a comprehensive mechanistic review

The intensive use of antibiotics resulted in the development of resistance, posing a significant global threat to human health. Natural products have garnered significant attention in modern drug discovery and development. Utilizing natural compounds and extracts, either alone or in combination with conventional antimicrobial drugs, could be a significant development in overcoming pathogen resistance mechanisms. Among these natural compounds, iridoids exhibited diverse biological activities, such as anti-inflammatory, antioxidant, anticancer, antidiabetic, antimicrobial, and neuroprotective properties. They are present in some widely available fruits, such as olives, noni, and berries. In this concise review, the utilization of iridoids as a promising approach to combat antimicrobial resistance is discussed. Iridoids exert their antimicrobial effects through various mechanisms including inhibition of microbial growth, disruption and permeability of microbial cell membranes, interference with metabolic pathways, and inhibition of bacterial efflux pumps. Their structural versatilities give them an advantage in targeting a variety of microorganisms.