Journal of Biotechnology & Biomaterials
Open Access

Abstract

Quorum sensing (QS) systems of Psuedomonas aeruginosa are implicated in elevating tolerance to antibiotics and to the activity of host immune systems. The levels of tolerance often exceed the highest deliverable doses, making efficient treatment unfeasible. Hence, identifying compounds that inhibit the QS systems controlling the expression of virulence factors and biofilm formation is highly attractive for drug development to treat bacterial infections. Ten different commercially available ethanolic extracts from indigenous plants, viz., Agathosma betulina, Boswellia serrata, Curtisia dentata, Kigelia africana, Ocoteabullata, Pelargonium sidoides, Prunus africana, Siphonochilus aethiopicus, Sutherlandia frutescens and Warbugia salutaris were assessed for their anti-QS and anti-virulence capabilities using Chromobacterium violaceum and P. aeruginosa , respectively. Quantitative violacein inhibition analysis revealed P. sidoides and S. frutescens extracts as the most effective quorum sensing inhibitors. Inhibition was found to be dose-dependent, with ≥80% violacein inhibition at ≥250 μL. A high biofilm percentage reduction (≥90%) for P. aeruginosa ATCC 35032 in the presence of S. frutescens and B. serrataextracts . In addition, QS-regulated virulence activities of P. aeruginosa , such as pyocyanin and LasBelastase were greatly (≥ 80%) reduced by K. africana, W. salutaris, S. frutescens, A. betulina extracts . Thus, these plant extracts may be suitable lead compounds and promising medicinal tools as quorum sensing inhibitors for the control of P. aeruginosa infections.

Biography

Cosa S has completed her PhD from the University of Fort Hare in May 2013 and is a postdoctoral researcher at the University Of Kwa Zulu Natal South Africa. She has published more than 10 papers in reputed journals.