الفهرس | Only 14 pages are availabe for public view |
Abstract Quorum sensing (QS) represents a major target for reducing bacterial pathogenicity and antibiotic resistance. At present, QS inhibition is a promising strategy to develop anti-infective agents that target bacterial signalling network without triggering bacterial resistance. This study has identified 17 plant-based materials of essential oils and extracts as potential sources of QS inhibitors, among which bergamot essential oil and aspidosperma extract were reported for the first time to the best of our knowledge. Initially, the conditions for growth and violacein production by the biosensor bacterium chromobacterium violaceum ATCC 12472 and CV026 were optimised to be utilized in the subsequent QS inhibition assays. Afterward, the anti-QS activity of 75 plant materials on C. violaceum CV026 was qualitatively screened using the agar diffusion method. Out of them, 17 plant-based materials exhibited QS inhibitory activity, judged by their capacity to inhibit violacein pigment production by test bacteria. In addition, 40 collected Gram-negative bacterial isolates including Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Acinetobacter baumannii were screened for acyl homoserine lactone (AHL) production. Out of these clinical isolates, six P. aeruginosa isolates were able to produce the AHL signal and induce violacein production by C. violaceum mutant strain CV026. These isolates were used to further confirm the QS inhibitory effect of selected plant materials |