Phytochemical composition and antimicrobial, and anti-quorum sensing activities of L. methanolic extract.

Background And Objectives: In this work, our aims were to investigate the antimicrobial resistance, and anti-quorum sensing activities of L. methanolic extract.

Materials And Methods: Antibacterial and antifungal activities were performed against thirteen bacteria and five fungal pathogens. Ultra-high performance liquid chromatography was used to identify the polyphenolic extract. The inhibition of pyocyanin production, proteolytic and elastolytic activity and swarming motility in PAO1 test strain were estimated.

Results: The methanolic extract from L. was dominated by chlorogenic acid (34.028 mg/g), rutin (26.05 mg/g), epicatechin (12.207 mg/g), gallic acid (11.157 mg/g), and caffeic acid 9.768 mg/g). Results showed antibacterial activities against almost all tested microorganisms with mean diameter of growth inhibition zone ranging from 6 ± 0 to 30 ± 0 mm for species and from 6 ± 0 to 22.66 ± 0.57 for bacterial strains. The lowest minimal inhibitory concentrations were recorded for ATCC 19115 and CECT 529 (0.14 mg/ml, respectively). The anti-quorum sensing activity of methanolic extract against showed a significant inhibition of swarming motility and an attenuation in virulence factors like pyocyanin production at low concentrations.

Conclusion: The obtained results indicates that L. extracts is a rich source of phenolic compounds and highlighted the possibilities uses of pomegranate to attenuate the expression of quorum sensing controlled factors in PAO1 strain.