Anti-quorum sensing effects of medicinal plants and chemical compounds: A new dimension against Pseudomonas aeruginosa and Staphylococcus aureus

Quorum sensing (QS) is a communication mechanism utilized by microorganisms to deliberately unleash virulence factors for their survival in living or non-living hosts. Biofilm, one of virulence factors that entrenches pathogenicity is developed through this process. Accumulation of biofilm as a result of heightened quorum sensing effect results in persistent spread of diseases and in extension, antibiotic resistance. Staphylococcus aureus and Pseudomonas aeruginosa are the major causative agents of nosocomial diseases which include wound and skin infections; so many synthetic and natural remedies have been introduced to reduce or entirely eliminate the development of QS-mediated virulence factors through repression of genes that encode them at the molecular level. Therefore, the activities of medicinal plants and chemical agents as inhibitors against QS-mediated virulence factors of P. aeruginosa and S. aureus strains are discussed and compared in this review. Overall, having the knowledge of target sites of plant extracts and chemical inhibitors and their mechanisms in these pathogenic bacterial cells as discussed in the review will assist scientists and medical practitioners in decision making for better therapeutic regimen in the treatment of bacterial diseases.