Quorum sensing inhibitors of plant origin: structure–activity relationships

The research into quorum sensing inhibitors is mainly directed towards fighting pathogenic bacteria resistant to therapy with antimicrobial drugs. Natural quorum sensing inhibitors may serve as an effective alternative to antibiotics, since they are less likely to cause the development of drug resistance of pathogenic microbiota. Currently, the search for effective inhibitor molecules and analysis of structure–activity relationships among natural compounds is considered to be the most obvious strategy towards solution of the antibiotic resistance problem. Since plants have co-evolved with the microbial environment and have been constantly exposed to bacterial infections, they successfully developed chemical mechanisms to fight external pathogens, in particular the quorum sensing inhibition. The review considers the secondary metabolites of various classes of plants such as terpenes, quinones, coumarins, stilbenes, alkaloids, curcuminoids, flavonoids, phenolic compounds, and their derivatives and analogues that possess quorum quenching activity. Some aspects of the structure–activity relationships for the described compounds are highlighted for the first time.The bibliography includes 139 references.