The Anti-inflammatory Effects of Probiotic-produced Exopolysaccharide

School of Food Science & Biotechnology, College of Agriculture and Life Sciences, Kyungpook National University, Daegu 702-701, KoreaReceived March 16, 2015/Revised June 12, 2015/Accepted June 15, 2015The present study isolated seven different kinds of probiotics from various food sources and identified them with Bacillus sp. and Lactobacillus sp. by 16S rDNA sequencing. Their supernatants were pre-pared after a 24 hr culture, and their effects on nitric oxide (NO) production in mouse RAW 264.7 cells were investigated. Among the treated samples, the culture supernatants of two strains (Bacillus sp. FG-1 and Lactobacillus sp. FG-6) significantly decreased NO production in LPS-activated RAW 264.7 cells. Moreover, they dramatically reduced the expression of pro-inflammatory genes such as COX-2, iNOS, and TNF-α. To examine whether exopolysaccharide (EPS) is responsible for the anti-in-flammatory effects of probiotics, EPS was purified from the culture supernatants of Bacillus sp. FG-1 and Lactobacillus sp. FG-6 strains. The EPS treatment produced by FG-1 and FG-6 strains decreased NO production in a dose-dependent manner in LPS-stimulated RAW 264.7 cells without affecting cell viability, while also reducing pro-inflammatory gene expression. Overall, these results suggest that EPS might be one of the key molecules responsible for the anti-inflammatory effects of probiotics. Keywords :