Background and Objectives: Non-aseptic fermentation ecosystems such as sourdough are the best substrate for lactic acid bacteria (LAB) with antimicrobial properties. This study was carried out to evaluate the antimicrobial properties of a dominant isolated LAB from whole barley sourdough against some food borne pathogens.
Materials & Methods: In this experimental study after molecular identification of LAB isolate, the antimicrobial properties of the isolate and it’s cell free culture filtrate (CCF) as native and neutralized CCF, obtained from logarithmic and stationary phases were investigated. For this purpose, disc diffusion and microdilution (antibacterial) and also overlay and agar spore spot (antifungal) methods were used. Results were compared by the one way analysis of variance.
Results: Sequencing results of PCR products lead to identification of Pediococcus stilesii as LAB isolate from barley sourdough. Results of investigating the antibacterial activities indicated that the highest antagonistic effect of the isolate and it’s native CCF obtained from the logarithmic phase were observed against Bacillus subtilis in comparison to other indicator bacteria (p<0.05). Furthermore, P. stilesii and it’s CCF had proper antifungal effects on Aspergillus flavus and Aspergillus niger.
Conclusion: Based on the results of this study, it is possible to use from the P.stilesii and it’s CCF as bio preservative for controlling some microbial indicators in food and medical technologies.