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In this study, the antibacterial activity of a grape seed extract (GSE) was examined against different Campylobacter strains. Growth inhibition was in the range from 5.08 to 6.97 log CFU/ml, demonstrating the strong capacity of the GSE to inhibit Campylobacter growth. Further dilution of the extract showed a minimal inhibitory concentration (MIC) of 20 mg/l and a minimal bactericidal concentration (MBC) of 60 mg/l against Campylobacter jejuni. GSE was fractioned by RP-HPLC and phenolic composition was determined by HPLC-DAD and HPLC-MS. The phenolic profile of GSE mainly consisted on flavonols, phenolic acids, catechins and proanthocyanidins, and anthocyanins. Among them, catechins and proanthocyanidins were the major compounds, representing 77.6% of total phenolic compounds determined. The analysis of the antibacterial activity against C. jejuni of the collected fractions showed that phenolic acids, catechins and proanthocyanidins were the main responsible of the behavior observed. These results showed that identification and quantification of the individual phenolic compounds of GSE could be feasible to standardize the production process to obtain an enriched extract potentially useful to control Campylobacter in the food chain. © 2012 Elsevier Ltd., This work was founded through Projects AGL 2009-07894 from the CSIC, ALIBIRD-CM-P 2009/AGR-1469 (Comunidad de Madrid) and CSD2007-00063FUN-C-FOOD (CONSOLIDER INGENIO 2010).

Campylobacter jejuni is a food pathogen which causes gastrointestinal conditions with an ever-increasing incidence at a global level. The antimicrobial power of wine and its components has been studied. Wines having 11.5% ethanol significantly reduced the viability of C. jejuni when they were diluted to 25% in water. The microbicidal power of red wine was higher than that of white wine. While pH does not seem to affect the viability of this pathogen, different phenolic compounds have an effect on it when tested at concentrations from 0 to 1000 mg/L. Gallic acid and p-hydroxybenzoic acid reduced the viability of C. jejuni at concentrations as low as 1 mg/L, but quercetin and catechin did not even affect it at concentrations of 1000 mg/L. Methyl gallate, epicatechin, synaptic acid, vanillic acid, and caffeic acid were microbicidal at concentrations starting at 10 mg/L. Tryptophol, ferulic acid, and cumaric acid were effective starting at 100 mg/L. According to this, wine constitutes an adverse environment for the survival of this pathogen. Furthermore, it would be interesting to study the possible use of phenolic compounds in wine as an alternative to the use of antimicrobial growth promoters against these bacteria in broilers.

In this work, an effort is made to elucidate the main hazard of microbial origin in winemaking, the presence of ochratoxin A (OTA), which has not yet been considered from an HACCP (Hazard Analysis and Critical Control Points) point of view, and for which a limit of

Lactic acid bacteria are important in enology since they undergo the malolactic fermentation, a process which main effect is the reduction of wine acidity and is almost indispensable in red wine-making. However, if this process is not well controlled during the elaboration of wine, alterations in wine quality due to bacteria metabolic activity can happen. Polyphenols are wine natural components in must and wine that can potentially affect the growth of lactic acid bacteria and the malolactic fermentation. In this paper, after describing the main features of the malolactic fermentation in wine, we review the use of different chemical substances to control growth of lactic acid bacteria in enology. Special attention is given to phenolic compounds, being revised the recent studies about the effect of polyphenols on the growth and metabolism of lactic acid bacteria in wine in order to establish the extent to which these compounds are involved in malolactic fermentation during wine-making. Finally, the potential use of phenolic extracts as new antimicrobial agents during wine-making, as a total or partial alternative to traditional treatments mainly using sulphur dioxide (SO 2 ) is discussed.