Identification and characterization of Diutina rugosa SD-17 for potential use as a probiotic

Abstract In this study, a new strain of D. rugosa isolated from chicken feces was identified and characterized. Phylogenetic analyses using the 5.8 internal transcribed spacer and 18S rDNA sequencing showed that this strain belongs to the species D. rugosa , and was thus named D. rugosa SD-17. Its general biological features were studied and compared with its closest related strain, D. rugosa ATCC 10571. The results showed that D. rugosa SD-17 formed a depression in the middle of the colony; furthermore, the cell wall was significantly thicker ( P  = 0.004) and the production of β-glucan was significantly higher ( P D. rugosa ATCC 10571. Intestinal environmental tolerance tests showed that D. rugosa SD-17 could thrive at the host intestinal temperature; approximately 45% of D. rugosa SD-17 survived at pH = 2 for 4 h and 0.3% of bile salts had no effect on growth. Colonization and adhesion tests showed that elimination of D. rugosa SD-17 was achieved after 20 h of oral administration, and the adhesion rate to Caco-2 cells reached 61.5% ( P D. rugosa SD-17 could be considered an appropriate probiotic candidate and may have potential use as a novel probiotic in animals.