Exopolysaccharide and extracellular metabolite production by Lactobacillus delbrueckii subsp. bulgaricus, grown on lactose in continuous culture.
Lactobacillus delbrueckii subsp. bulgaricus NCFB 2483, when grown on lactose in continuous culture, showed increasing specific yields and volumetric productivities of exopolysaccharide (EPS) with increasing dilution rate. Specific and volumetric productivities of lactate and galactose, as extracellular metabolites, increased in response to the incremental changes in the dilution rate up to 0.4 h(-1). Elevated Y(p/s) values determined for EPS (0.025 g EPS x g lactose(-1)) at the dilution rates of 0.3 h(-1)-0.4 h(-1), relative to those determined at lower dilution rates, suggest a diversion of carbon flux towards EPS being associated with the higher rates of growth.
Institute of Technology and Engineering, Massey University, Palmerston North, New Zealand. Alan.Welman@fonterra.com
Alan
A
Welman
Ian
I
Maddox
Richard
R
Archer
D019149:Bioreactors / Q000382:microbiology; D018929:Cell Culture Techniques / Q000379:methods*; D002455:Cell Division / Q000502:physiology; D045604:Extracellular Fluid / Q000378:metabolism*; D005690:Galactose / Q000096:biosynthesis*; D019344:Lactic Acid / Q000096:biosynthesis*; D007778:Lactobacillus / Q000145:classification / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D007785:Lactose / Q000378:metabolism*; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis*; D013045:Species Specificity; D013223:Statistics as Topic
D011135:Polysaccharides, Bacterial; C085953:exopolysaccharide, Bacillus; D019344:Lactic Acid; D007785:Lactose; D005690:Galactose