Antibacterial Activity of Cell-Free Culture Supernatant of Bacteriocinogenic Pediococcus pentosaceus IO1 against Staphylococcus aureus Inoculated in Fruit Juices

Staphylococcus aureus is a major food-borne pathogen worldwide and a frequent contaminant of fruit juices. This study aimed to evaluate the antibacterial activity of bacteriocin-containing Cell-Free Culture Supernatants (CFCS) of Pediococcus pentosaceus IO1 against S. aureus inoculated in fruit juices, as well as their impact on the juice sensory attributes.

The orange and watermelon juice samples were treated with bacteriocin supernatant at different concentrations (1, 5, and 10% v/v) and the sensory attributes were evaluated using a 5-point hedonic scale and thereafter inoculated with a culture of S. aureus. Then, the inhibitory effect of bacteriocin-containing CFCS of P. pentosaceus IO1 against S. aureus in the fruit juices was evaluated by in situ and plate assays.

The 10% (v/v) bacteriocin-containing CFCS exhibited the highest antibacterial activity, reducing S. aureus counts in pasteurized orange and watermelon juices by 1.42 and 2.12 log Colony Forming Units (CFU)/ml, respectively, and by 1.03 and 0.88 log CFU/ml in unpasteurized orange and watermelon juices, respectively, compared to the control. The taste, colour, and overall acceptability of pasteurized orange and watermelon juices treated with 1% (v/v) bacteriocin supernatant and 0.1% (w/v) sodium benzoate were not significantly different (p=0.228) from those pasteurized orange and watermelon juices without preservative.

The bacteriocin produced by P. pentosaceus IO1 could be used as a natural preservative in fruit juices to control S. aureus.DOI: 10.18502/jfqhc.9.3.11151