title: Effects of pH and corn steep liquor variability on mannitol production by Lactobacillus intermedius NRRL B-3693.
abstract: Lactobacillus intermedius NRRL B-3693 produced mannitol, lactic acid, and acetic acid when grown on fructose at 37 degrees C. The optimal pH for mannitol production from fructose by the heterofermentative lactic acid bacterium (LAB) in pH-controlled fermentation was at pH 5.0. It produced 160.7 +/- 1.1 g mannitol in 40 h with a volumetric productivity of 4.0 g l(-1) h(-1) in a simplified medium containing 250 g fructose, 50 g corn steep liquor (CSL), and 33 mg MnSO(4) per liter. However, the mannitol production by the LAB was severely affected by the variability of CSL. The supplementation of CSL with soy peptone (5 g/l), tryptophan (50 mg/l), tryptophan (50 mg/l) plus tyrosine (50 mg/l), or commercial protease preparation (2 ml/100 g of CSL) enhanced the performance of the inferior CSL and thus helped to overcome the nutrient limitations.
authors.affiliation: Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, US Department of Agriculture, Peoria, IL 61604, USA. Badal.Saha@ars.usda.gov
authors.forename: Badal C
authors.initials: BC
authors.lastname: Saha
authors.forename: F Michael
authors.initials: FM
authors.lastname: Racine
mesh_terms: D019149:Bioreactors / Q000382:microbiology; D003470:Culture Media / Q000737:chemistry* / Q000378:metabolism; D005285:Fermentation; D005632:Fructose / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus / Q000737:chemistry / Q000378:metabolism*; D008353:Mannitol / Q000378:metabolism*; D003313:Zea mays / Q000737:chemistry* / Q000382:microbiology
chemical_list: D003470:Culture Media; D005632:Fructose; D008353:Mannitol