title: Effect of Oxygen Tension and Medium Components on Monomer Distribution of Alginate.
abstract: Alginate is a natural biopolymer composed of mannuronic and guluronic acid monomers. It is produced by algae and some species of Azotobacter and Pseudomonas. This study aims to investigate the effect of dissolved oxygen tension (DOT) and growth medium substrate and calcium concentrations on the monomeric composition of alginate produced by Azotobacter vinelandii ATCC® 9046 in a fermenter. Results showed that alginate production increased with increasing DOT from 1 to 5 %. The highest alginate production was obtained as 4.51 g/L under 20 g/L of sucrose and 50 mg/L of calcium at 5 % DOT. At these conditions, alginate was rich in mannuronic acid (up to 61 %) and it was particularly high at low calcium concentration. On the other hand, at extreme conditions such as high DOT level (10 % DOT) and low sucrose concentration (10 g/L), guluronic acid was dominant (ranging between 65 and 100 %).
authors: Department of Environmental Engineering, Middle East Technical University, 06800, Ankara, Turkey.
authors: Çiğdem
authors: Ç
authors: Kıvılcımdan Moral
authors: Özdemir
authors: Ö
authors: Doğan
authors: Faika Dilek
authors: FD
authors: Sanin
mesh_terms: D000464:Alginates / Q000737:chemistry* / Q000378:metabolism*; D016948:Azotobacter vinelandii / Q000187:drug effects / Q000378:metabolism / Q000502:physiology; D018533:Biomass; D002118:Calcium / Q000494:pharmacology; D003470:Culture Media / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D005285:Fermentation / Q000187:drug effects; D020723:Glucuronic Acid / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D006603:Hexuronic Acids / Q000737:chemistry / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry* / Q000494:pharmacology*; D013312:Stress, Physiological / Q000187:drug effects*; D013395:Sucrose / Q000494:pharmacology
chemical_list: D000464:Alginates; D003470:Culture Media; D006603:Hexuronic Acids; D013395:Sucrose; D020723:Glucuronic Acid; D010100:Oxygen; D002118:Calcium