Title: Phytochemicals in lowbush wild blueberry inactivate Escherichia coli O157:H7 by damaging its cell membrane
Authors: Lacombe A, Tadepalli S, Hwang C, Wu VC
Journal: Foodborne Pathog Dis
Accepted date: 2013 Jun 5
Interpretive summary: Extracts from lowbush blueberry fruits have been shown to kill microbes. This study identified the chemicals in the extract and the mechanism against a foodborne pathogen, Escherichia coli O157:H7. Blueberries extract was separated into four phenolic fractions, blueberry phenolics, monomeric phenolic acids, anthocyanins plus proanthocyanidins, anthocyanins. The effects of these polyphenols in killing E. coli O157:H7 and damaging the cell membrane of E. coli O157:H7 were determined. Monomeric phenolic acids at 0.4 g/L gallic acid equivalent (GAE), anthocyanins plus proanthocyanidins at 0.9 g/L GAE, or anthocyanins at 0.65 g/L GAE were capable of killing 5 log CFU/ml of E. coli O157:H7. These polyphenols killed E. coli O157:H7 by damaging and increasing the permeability of the cell membrane. Findings from this study will help food producers in using blueberry constituents as natural preservatives in food products.
Publication date: 2013 Nov