Isolation, Screening, and Identification of Staphylococcus epidermidis with Effective Probiotic Attributes

In this investigation, Staphylococcus epidermidis SAS1 strain was isolated and assessed for its probiotic, antioxidant, antimicrobial, and anti-cancerous properties. The strain demonstrated no gelatinase, DNase, or hemolytic activity, highlighting its safety for human use. Comprehensive tests were conducted to assess its probiotic potential, including its tolerance and survival under in-vitro gastric conditions, such as acidic pH and bile salts as well as antimicrobial potential. Furthermore, the CAE (crude antibacterial extract) extracted from S. epidermidis exhibited potent free radical scavenging activities against the different radicals such as super anion, 2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS), nitrogen oxide, and hydroxyl. The SAS1 strain also exhibited ferric ion and cupric-reducing antioxidant power. The anti-cancerous potential of the strain was also determined by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay, which was carried out using the human colorectal adenocarcinoma cell line HT-29. An IC₅₀ value of 8.30 ± 0.35 µg/mL and morphological changes in HT-29 cells, including apoptotic damage, cell shrinkage, and release of cellular content, depicted the anti-cancerous nature of the strain. The potent lipase inhibition activity of SAS1 may expand the scope of treating diseases associated with lipid metabolism. These findings underscore the efficacy in vitro efficacy of the S. epidermidis SAS1 strain as a probiotic, antioxidant, lipase inhibitor, and anti-cancerous agent, which can be further studied for potential treatment of colon cancer and other therapeutic applications.