Younes1* and G. Ibrahim2
(1) Center for Biological Control Research and Studies, Faculty of Agricultural Engineering, Damascus University, Syria; (2) Department of Plant Protection and Center for Biological Control Research and Studies, Faculty of Agricultural Engineering, Damascus University, Syria.
*Email address of the corresponding author: [email protected]
Bacterial quorum sensing (QS) enables bacterial biofilm formation and colonization of plant host tissue through virulence factors. Therefore, quorum quenching (QQ), the disruption of the QS communication, is an alternative antibacterial treatment. In this study, a methanolic extract of Eucalyptus tereticornis bark was used to inhibit the growth of the black mold bacterium Xanthomonas campestris pv. campestris (Xcc) and biofilm formation that protects the bacteria from external conditions. The results obtained showed the ability of the methanolic extract of E. tereticornis bark to inhibit the growth of Xcc, with a minimum inhibitory concentration (MIC) of 11.5 mg/mL. In addition, the results obtained showed the extract’s ability to inhibit biofilm formation at concentrations that were ineffective on bacterial growth (6.25, 3.125, and 1.565 mg/mL), with inhibition rates reaching 42.8, 29.4, and 23.53%, respectively. This indicates the extract’s effect as a QS inhibitor. Therefore, E. tereticornis bark extract can be used as a natural alternative to combat Xcc bacteria by targeting its QS system.
Quorum sensing, quorum quenching, Xcc, bacterial growth, biofilm.
https://doi.org/10.22268/AJPP-001494