Changes in antagonistic activity of lactic acid bacteria induced by their response to technological factors

Authors

• Dovile Jonkuviene Kaunas University of Technology
• Joana Šalomskienė Kaunas University of Technology
• Asta Abraitienė Vilnius University
• Irena Mačionienė Kaunas University of Technology
• Jūratė Repečkienė Nature Research Center
• Jūratė Stankienė Kaunas University of Technology
• Lina Vaičiulytė-Funk Kaunas University of Technology

DOI: https://doi.org/10.23986/afsci.50936

Keywords:

lactic acid bacteria, antimicrobial activity, impact, technological factors, antimicrobial substances

Abstract

This study examined the changes in antagonistic activity of selected lactic acid bacteria (LAB) in response to technological factors used in food production. The antimicrobial activity of 12 selected LAB strains was assessed against the bacterial and fungal strains using the agar well diffusion method. Sodium chloride (NaCl) 6.5–8.0%, glucose 20-30% and pH 4.0, pH 8.0 and higher were the most crucial factors in reducing the spectra of the microorganisms antagonized. Heating at 80 °C or 100 °C had a greater negative impact than 63 °C on the antifungal activity of LAB. Freezing at –72 °C eliminated the antifungal activity, or it changed from fungicidal to fungistatic. Although each LAB demonstrated the ability to retain antimicrobial activity induced by various technological factors, Lactococcus lactis 768/5 was superior in retaining high antimicrobial activity against tested indicator strains.