Increase of antioxidant capacity of the lowbush blueberry (Vaccinium angustifolium) during fermentation by a novel bacterium from the fruit microflora

Members of the genus Vaccinium, such as blueberry and cranberry, are known to be excellent sources of antioxidant phenolic compounds, for example anthocyanins, flavonols and phenolic acids. The fruit also provides a natural habitat for numerous microorganisms. Interaction between the fruit and the microflora might affect the antioxidant phenolic compounds. The aim of this study was to investigate the effects on phenolic content and antioxidant capacity of wild blueberry fermented by a newly identified bacterium isolated from blueberry-fruit surface microflora, Serratia vaccinii. Increase in the antioxidant capacity following fermentation of blueberries by the novel bacterium, as determined with the 2,2'-diphenyl-1-picrylhydrazyl method, was attributed not only to an increase in total phenolics, but also to a change in the phenolic profile, as demonstrated by the production of gallic acid and of a novel compound of phenolic or phenylpropanoic structure. (c) 2005 Society of Chemical Industry.