Antimicrobial Activity of Wine in Relation to Bacterial Resistance to Medicinal Antibiotics

Although antimicrobial properties of wine have been extensively studied, antimicrobial effects of wine in relation to bacterial resistance to medicinal antibiotics have not been examined. Therefore, our aim was to determine whether bacterial resistance to antibiotics can be related to their resistance to red wine as an unspecific antimicrobial medium. The organisms studied were Salmonella enteritidis (ATCC 13076), Escherichia coli (ATCC 25922), and two clinical isolates which exhibited different resistance to antibiotics, ESBL - producing Escherichia coli UR 3612 and Salmonella enteritidis KK 962. The time-kill curves method was used. The minimal incubation time of the bacterial suspension with wine, necessary for prevention of bacterial growth, was 3 and 20 min for E. coli ATCC and ESBL E. coli respectively. This was associated with susceptibility testing in which E. coli ATCC proved highly sensitive in contrast to ESBL-producing E. coli, which exhibited resistance to a spectrum of antimicrobial drugs of different classes regarding their principal mechanism of action. In the case of S. enteritidis strains, they were similar in their susceptibility against test antibiotics and time-kill curves following exposure to wine. Bacterial resistance to wine is closely associated with bacterial resistance to antimicrobial drugs. The exact mechanisms of antimicrobial activity of wine are still a matter of debate. However, wine might be less susceptible to bacterial resistance development and may include mechanisms different from those of medicinal antibiotics. The present study represents an initial contribution to this important subject which has been practically unexplored.