In vitro Evaluation of Immunomodulatory and Antioxidant Potential of Isolated Lactic Acid Bacteria from Iranian Dairy Products: An Insight into beneficial potential of cheese-derived isolates.

In the current study, two isolates from Iranian dairy products, Koozeh cheese, were screened and identified through evaluation of different biological activities, including different lactic acid bacteria assessment, such as tolerance to different temperatures, pH levels, and bile salt conditions. Additional tests such as hydrophobicity, co-aggregation, auto-aggregation, hemolytic activity, and competition assay against E.coli strain (PTCC No: 1330, ATCC 8739) were also conducted. The study further investigated molecular profiling through 16 S rRNA sequencing, antioxidant activity, and the ability of the isolates to mitigate lipopolysaccharide (LPS)-induced inflammation in the Caco-2 cell line. The results indicated that the isolates belong to the lactic acid bacterium, Lactobacillus brevis, with moderate hydrophobicity, co-aggregation, auto-aggregation potency, and proper inhibitory effect against E. coli. Both isolates reduced TNF-α and IL-6 concentrations in response to LPS challenge in the Caco-2 cell line and demonstrated a great ability to scavenge DPPH radicals. These findings suggest that lactic acid bacteria from Iranian native dairy products may offer potential health benefits for modulating inflammation and promoting gut health. However, further investigation is necessary to fully explore these properties.