Abstract
Exopolysaccharide (EPS) was produced by Klebsiella pneumoniae K63 grown in fed-batch cultures using different procedures of the supply of carbon or nitrogen (N) source, or both. Cultures grown with excess of glucose and limitation or exhaustion of N produced 54.8 and 47.4 gEPS l−1, respectively. These cultures also led to an accumulation of `overflow' metabolites representing more than 16% of carbon conversion. The consistency indexes (K) obtained to the end of the cultures, characteristic of the rheological property of the biopolymer, were 16.4 Pa sn for N deficiency and 5.2 Pa sn for N limitation conditions. The simultaneous limitation of glucose and N decreased the excretion of co-metabolites (6.4% of carbon conversion) and the EPS production (18.1 gEPS l−1), while improving the quality of the polysaccharide, characterized by the highest K of 126.2 Pa sn and the highest pseudoplasticity degree (flow behaviour index, n=0.2).
Similar content being viewed by others
References
Banks GT, Browning PD (1987) Fermentation process for the production of polysaccharides. US Patent, number 4692408.
De Vuyst L, Van Loo J, Vandamme EJ (1987) Two-step fermentation process for improved xanthan production by Xanthomonas campestris NRRL-B-1459. J. Chem. Tech. Biotechnol. 39: 263–273.
Farrés J, Carminal G, López-Santín J (1997) Influence of phosphate on rhamnose-containing exopolysaccharide rheology and production by Klebsiella I-714. Appl. Microbiol. Biotechnol. 48: 522–527.
Iversen JJL (1987) The pH mediated effects of initial glucose concentration on the transitory occurrence of extracellular metabolites, gas exchange and growth yields of aerobic batch cultures of Klebsiella pneumoniae. Biotechnol. Bioeng. 30: 352–362.
Joseleau JP, Marais MF (1979) Structure of the capsular polysac-charide of Klebsiella K-type 63. Carbohydr. Res. 77: 183–190.
Kobayashi T, Adachi S, Nakanishi K, Matsuno R (2000) Synthesis of alkyl glycosides through-glucosidase-catalyzed condensation in an aqueous-organic biphasic system and estimation of the equilibrium constants for their formation. J. Mol. Catal. B: Enzym. 11: 13–21.
Mengistu Y, Edwards C, Saunders JR (1994) Continuous culture studies on the synthesis of capsular polysaccharide by Klebsiella pneumoniae K1. J. Appl. Bacteriol. 76: 424–430.
Neijssel OM, Tempest DW (1975) The regulation of carbohydrate metabolism in Klebsiella aerogenes NCTC 418 organisms, growing in chemostat culture. Arch. Microbiol. 106: 251–258.
Paul FMB, Perry DF, Monsan PF (1995) Nouvelle souche de Klebsiella pneumoniae, subsp. pneumoniae et procédé de production d'un polysaccharide contenant L-fucose. Demande de brevet en France No. 95 00898.
Sutherland IW (1982) Biosynthesis of microbial exopolysaccharides. Adv. Microbiol. Physiol. 23: 79–150.
Teixeira de Mattos MJ, Neijssel OM (1997) Bioenergetic consequences of microbial adaptation to low-nutrients environments. J. Biotechnol. 59: 117–126.
Vanhooren PT, Vandamme EJ (1999) L-fucose: occurrence, physiological role, chemical, enzymatic and microbial synthesis. J. Chem. Technol. Biotechnol. 74: 479–497.
Rights and permissions
About this article
Cite this article
Ramírez-Castillo, M., Uribelarrea, J. Improved process for exopolysaccharide production by Klebsiella pneumoniae sp. pneumoniae by a fed-batch strategy. Biotechnology Letters 26, 1301–1306 (2004). https://doi.org/10.1023/B:BILE.0000044923.02460.de
Issue Date:
DOI: https://doi.org/10.1023/B:BILE.0000044923.02460.de