Anti‐Campylobacter activity of resveratrol and an extract from waste Pinot noir grape skins and seeds, and resistance of Camp. jejuni planktonic and biofilm cells, mediated via the CmeABC efflux pump

Aims To define anti-Campylobacter jejuni activity of an extract from waste skins and seeds of Pinot noir grapes (GSS) and of resveratrol, and possible resistance mechanisms, and the influence of these on C. jejuni morphology. Methods and results Using gene-specific knock-out C. jejuni mutants and an efflux-pump inhibitor, we show CmeABC as the most active efflux pump for extrusion across the outer membrane of GSS extract and resveratrol. Using polystyrene and pig small-intestine epithelial (PSI) and human foetal small intestine (H4) cell lines, GSS extract shows efficient inhibition of adhesion of C. jejuni to these abiotic and biotic surfaces. Conclusions Low doses of GSS extract can inhibit C. jejuni adhesion to polystyrene surfaces and to PSI and H4 cells, and can thus modulate C. jejuni invasion and intracellular survival. Significance and Impact of Study An understanding of the activities of GSS extract and resveratrol as bacterial growth inhibitors and the specific mechanisms of cell accumulation is crucial for our understanding of C. jejuni resistance. GSS extract inhibition of C. jejuni adhesion to abiotic and biotic surfaces provides a further step towards the application of new innovative strategies to control Campylobacter contamination and infection via the food chain. This article is protected by copyright. All rights reserved.