title: Influence of phosphate on rhamnose-containing exopolysaccharide rheology and production by Klebsiella I-714.
abstract: Physiological conditions enhancing rhamnose-containing polysaccharide synthesis by Klebsiella I-714 were studied in batch culture (0.3-l and 2-l bioreactors). The four carbon sources tested, sucrose, sorbitol, Neosorb and Cerelose, allowed exopolysaccharide production. Larger amounts of polymer were produced when high carbon/nitrogen ratios and complex nitrogen sources were used. Exopolysaccharide synthesis was greatest at 30 degrees C, which was a suboptimal growth temperature. A reduction in the phosphate content of the medium enhanced rhamnose-containing polysaccharide production. When the initial carbon source concentration was augmented, byproducts other than exopolysaccharide were formed. Rhamnose-containing polysaccharide rheology can be modulated by changing the phosphate content of the medium.
authors.affiliation: Departament d'Enginyeria Química, Universitat Autònoma de Barcelona, Bellaterra, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Farrés
authors.forename: G
authors.initials: G
authors.lastname: Caminal
authors.forename: J
authors.initials: J
authors.lastname: López-Santín
mesh_terms: D019149:Bioreactors; D002021:Buffers; D002244:Carbon / Q000378:metabolism; D003470:Culture Media / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism / Q000494:pharmacology; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000737:chemistry; D012210:Rhamnose / Q000032:analysis*; D012212:Rheology; D013012:Sorbitol / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism
chemical_list: D002021:Buffers; D003470:Culture Media; D010710:Phosphates; D011135:Polysaccharides, Bacterial; D013012:Sorbitol; D013395:Sucrose; D002244:Carbon; D005947:Glucose; D009584:Nitrogen; D012210:Rhamnose