title: Preparation, characterization and immunomodulatory activity of selenium-enriched exopolysaccharide produced by bacterium Enterobacter cloacae Z0206.
abstract: The tolerant-selenium exopolysaccharide-producing bacterial strain Enterobacter cloacae Z0206 was batch cultured in PDA medium containing optimal concentration of sodium selenite. Selenium was accumulated efficiently in Enterobacter cloacae Z0206 during cultivation with selenium. Inorganic selenite could be transformed into organic forms. Selenium-enriched exopolysaccharide (Se-ECZ-EPS-1) was purified from the fermentation liquid. Selenium content of Se-ECZ-EPS-1 was 12.962microg/g. Se-ECZ-EPS-1 with Mw of 29,300Ka was composed of Glc, Gal and Mann with molar ratio of 8.530:0.061:0.706. Administration of Se-ECZ-EPS-1 to cyclophosphamide (CP)-exposed animals resulted in improvement of cellular and humoral immune responses. These findings indicated that Se-ECZ-EPS-1 may act as potent immunomodulatory agents.
authors.affiliation: Key Laboratory of Molecular Animal Nutrition of Ministry of Education, Feed Science Institute, Zhejiang University, No. 164 Qiutao North Road, Hangzhou 310029, PR China.
authors.forename: C L
authors.initials: CL
authors.lastname: Xu
authors.forename: Y Z
authors.initials: YZ
authors.lastname: Wang
authors.forename: M L
authors.initials: ML
authors.lastname: Jin
authors.forename: X Q
authors.initials: XQ
authors.lastname: Yang
mesh_terms: D000818:Animals; D001711:Biotransformation; D002848:Chromatography, DEAE-Cellulose; D002851:Chromatography, High Pressure Liquid; D016972:Enterobacter cloacae / Q000378:metabolism*; D007155:Immunologic Factors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D018625:Microscopy, Atomic Force; D009929:Organ Size / Q000187:drug effects; D011134:Polysaccharides / Q000096:biosynthesis / Q000737:chemistry / Q000494:pharmacology*; D012643:Selenium / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013154:Spleen / Q000187:drug effects / Q000276:immunology; D013950:Thymus Gland / Q000187:drug effects / Q000276:immunology
chemical_list: D007155:Immunologic Factors; D011134:Polysaccharides; D012643:Selenium