title: Optimization of culture medium and growth conditions for production of L-arabinose isomerase and D-xylose isomerase by Lactobacillus bifermentans.
abstract: Lactobacillus bifermentans was used to produce the intracellular enzymes L-arabinose isomerase and D-xylose isomerase. Various factors of cultivation (temperature, pH, or incubation period) and culture medium composition (mineral salts, carbon and nitrogen source) were studied to select the conditions that maximize production of these enzymes. Arabinose isomerase and xylose isomerase activities were 9.4 and 7.24 U/ml, respectively. They were highest at 9 h of cultivation in the optimized medium, 1.6 times higher than that in the basic MRS broth. The optimal medium composition and cultivation conditions were determined. On the other hand, the strain required for growth Tween 80 (1 g/l) and a source of inorganic nitrogen (e.g. ammonium citrate). The bacterium had no requirement for sodium acetate for both growth and production of isomerases. The production rate of enzymes was increased when metal ions were added and mainly manganese (2.5 mM).
authors.affiliation: Laboratoire de microbiologie industrielle UMR FARE 614, Universite de Reims Champagne Ardenne, Moulin de la Housse BP 1039, 51687 Reims cedex 2, France. sebastien.givry@univ-reims.fr
authors.forename: S
authors.initials: S
authors.lastname: Givry
authors.forename: F
authors.initials: F
authors.lastname: Duchiro
mesh_terms: D019747:Aldose-Ketose Isomerases / Q000096:biosynthesis*; D001426:Bacterial Proteins / Q000096:biosynthesis*; D019343:Citric Acid; D003470:Culture Media; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus / Q000254:growth & development / Q000378:metabolism*; D008345:Manganese; D011136:Polysorbates; D000644:Quaternary Ammonium Compounds; D013696:Temperature; D013997:Time Factors; D014994:Xylose / Q000096:biosynthesis*
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D011136:Polysorbates; D000644:Quaternary Ammonium Compounds; D019343:Citric Acid; D008345:Manganese; C481046:ammonium citrate; D014994:Xylose; D019747:Aldose-Ketose Isomerases; C019715:L-arabinose isomerase; C023298:xylose isomerase