Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 17 4 2025 07 30 613 622 EN Maryam Firoozi Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Hamadan University of Medical Sciences, Hamadan, Iran Mahdieh Shirzad Department of Microbial Biotechnology, School of Biology and Center of Excellence in Phylogeny of Living Organism, College of Science, University of Tehran, Tehran, Iran Elahe Motevaseli Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran Razieh Dalirfardouei Department of Medical Biotechnology, School of Advanced Medical Sciences and Technologies, Hamadan University of Medical Sciences, Hamadan, Iran Mohammad Hossein Modarresi Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Rezvan Najafi Department of Molecular Medicine, School of Advanced Medical Sciences and Technologies, Hamadan University of Medical Sciences, Hamadan, Iran; Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran 2024 09 25 2025 06 28 Background and Objectives: Bacterial polysaccharides have diverse applications, including antimicrobial compounds, bio-preservatives, prebiotics, and wound-healing hydrogels. Weissella confusa is notable for its high polysaccharide yield among lactic acid bacteria. Materials and Methods: The bacteria were identified via 16s rRNA and exopolysaccharide (EPS) production was performed in a 10% skim milk and 10% sucrose medium. FT-IR, SEM, and HPTLC analyzed functional groups, spatial structure, and EPS units. Moreover, MTT assay, DPPH, and Kirby-Bayer disk method assessed cell proliferation, antioxidant activity, and antimicrobial effects of EPS. Additionally, Prebiotic potential and growth kinetics of exopolysaccharide were examined using the Thitiratsakul method. Furthermore, EPS effects on MMP and TIMP gene expression in fibroblast cells were evaluated. Results: The purified polysaccharide from W. confusa B4-2 (Accession: KY290603), with a yield of 53 g/L, consists of glucose, fructose, and diglucuronic acid. This non-toxic polysaccharide (99-100% cell survival) exhibits 75% free radical scavenging activity along with significant antimicrobial effects against Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. It also shows a high prebiotic score (0.912), accelerating wound healing in fibroblast cells while reducing collagen-degrading gene expression, particularly matrix metalloproteinases (MMPs). Notably, exopolysaccharides downregulated MMP1, MMP2, MMP3, and MMP9 gene expression levels by approximately 1.3, 1.2, 1.5, and 1.16 times, respectively. Conclusion: These features highlight the commercial significance of W. confusa in the food, pharmaceutical, and health industries, surpassing lactobacilli with lower production yields. https://ijm.tums.ac.ir/index.php/ijm/article/view/5050 https://ijm.tums.ac.ir/index.php/ijm/article/download/5050/1805