Functional Properties of Lactic Acid Bacteria Postbiotics Isolated from Tarhana Samples

Area of Science:

• Food Science and Technology
• Microbiology
• Biotechnology

Background:

• Tarhana, a traditional Turkish fermented soup, is a source of lactic acid bacteria (LAB).
• Postbiotics, beneficial compounds derived from microorganisms, are gaining interest as alternatives to probiotics.

Purpose of the Study:

• To characterize postbiotics derived from LAB isolated from tarhana.
• To evaluate the antimicrobial and antioxidant properties of these postbiotics.
• To assess their safety and compare different production methods (cell-free supernatant vs. heat-killed cells).

Main Methods:

• Lactic acid bacteria were isolated from tarhana.
• Postbiotics were prepared as cell-free supernatants (CFS) and heat-killed (HK) cell fragments.
• Antimicrobial activity was tested against foodborne pathogens using the well diffusion method.
• Antioxidant activity was assessed using DPPH radical scavenging assay.
• Cytotoxicity was evaluated on HT-29 cells.
• Chemical analyses included HPLC and FT-IR.

Main Results:

• Postbiotics exhibited significant antimicrobial activity against Staphylococcus aureus and Listeria monocytogenes.
• Antimicrobial activity was attributed to acidic compounds.
• Identified Pediococcus pentosaceus strains produced the most potent postbiotics.
• Postbiotics demonstrated antioxidant activity and reduced cancer cell viability in a dose-dependent manner.
• No significant differences in activity or structure were found between CFS and HK postbiotic forms.

Conclusions:

• Postbiotics derived from tarhana LAB possess significant antimicrobial and antioxidant properties.
• Both CFS and HK forms are effective, suggesting flexibility in application.
• These findings highlight the potential of tarhana-derived postbiotics for the food and health industries.