Tehran University of Medical Sciences Iranian Journal of Microbiology 2008-3289 18 4 2026 08 04 509 517 Zohreh Amirheidari Pharmaceutics Research Center, Institue of Pharmaceutical Sciences, Kerman University of Medical Sciences, Kerman, Iran Farshid Ataollahi Pharmaceutical Sciences and Cosmetic Products Research Center, Institue of Pharmaceutical Sciences, Kerman University of Medical Sciences, Kerman, Iran Bagher Amirheidari Pharmaceutics Research Center, Institue of Pharmaceutical Sciences, Kerman University of Medical Sciences, Kerman, Iran; Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran Hamid Forootanfar Pharmaceutical Sciences and Cosmetic Products Research Center, Institue of Pharmaceutical Sciences, Kerman University of Medical Sciences, Kerman, Iran; Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran Mojtaba Shakibaie Pharmaceutical Sciences and Cosmetic Products Research Center, Institue of Pharmaceutical Sciences, Kerman University of Medical Sciences, Kerman, Iran; Department of Pharmaceutical Biotechnology, Faculty of Pharmacy, Kerman University of Medical Sciences, Kerman, Iran Mehdi Ahmadinejad Department of Anesthesiology, Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran Zahra Khoshnam Department of Anesthesiology, Faculty of Medicine, Kerman University of Medical Sciences, Kerman, Iran Maryam Nooshadokht Herbal and Traditional Medicines Research Center, Institute of Pharmaceutical Sciences, Kerman University of Medical Sciences, Kerman, Iran Mohammad Shabani Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran Maryam Ramezani Nejad Herbal and Traditional Medicines Research Center, Institute of Pharmaceutical Sciences, Kerman University of Medical Sciences, Kerman, Iran Zahra Amirheidari Oral and Dental Diseases Research Center, Kerman University of Medical Sciences, Kerman, Iran 2026 01 08 2026 07 12 Background and Objectives: A selenium (Se) enriched Lactobacillus brevis was applied as mouthwash to relieve mouth ulcers and regulate oral pathogens. The persistence of four frequent oral pathogens (Pseudomonas, Klebsiella, Proteus, and Enterobacter) and the quantity of mouth lesions were to be measured after exposure to the above probiotic. Susceptibility of the pathogens was also examined. Materials and Methods: In this randomized double-blind controlled clinical trial, 60 ICU patients were allocated into three groups equally (to receive normal saline, chlorhexidine, and Se-probiotic) every 6 hours for 1 week. The utilized Lactobacillus brevis was previously separated from a traditional dairy product and its enrichment was accomplished through streaking on MRS plates supplemented with sodium selenite. Results: Klebsiella and Pseudomonas were the most frequent initial pathogens, from which Pseudomonas were totally omitted from the probiotic group. The Se-probiotic existed in the mouth cavity of the test group six hours after the last dose. In the probiotic group, the number of oral lesions were significantly reduced. Conclusion: Clearance of Pseudomonas from mouth cavity and significant decrease in the quantity of mouth ulcers are considerable achievements. Hence, the applied Se-supplemented mouthwash exhibited promising capability to be considered as a potential oral hygiene formulation. https://ijm.tums.ac.ir/index.php/ijm/article/view/6044 https://ijm.tums.ac.ir/index.php/ijm/article/download/6044/1911