title: A continuous lactic acid production system using an immobilized packed bed of Lactobacillus helveticus.
abstract: A 5 l packed bed bioreactor was used to study the effect of initial lactose concentration and hydraulic retention time (HRT) on cell growth, lactose utilization and lactic acid production. Up to 95% of the initial lactose concentration was utilized at longer HRTs (30-36 h). The study showed that lactic acid production increased with increases in HRT (12-36 h) and initial lactose concentrations. The highest lactic acid production rate (3.90 g l(-1) h(-1)) was obtained with an initial lactose concentration of 100 g/l and an HRT of 18 h, whereas the lowest lactic acid production rate (1.35 g l(-1) h(-1)) was obtained with an initial lactose concentration of 50 g/l and an HRT of 36 h. This suggested that optimal lactic acid production can be achieved at an HRT of 18 h and initial lactose concentration of 100 g/l.
authors.affiliation: Department of Biological Engineering, Dalhousie University, P.O. Box 1000, Halifax, Nova Scotia, B3J 2X4, Canada.
authors.forename: M S A
authors.initials: MS
authors.lastname: Tango
authors.forename: A E
authors.initials: AE
authors.lastname: Ghaly
mesh_terms: D019149:Bioreactors; D002455:Cell Division; D005285:Fermentation; D019344:Lactic Acid / Q000096:biosynthesis*; D007778:Lactobacillus / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D007785:Lactose / Q000378:metabolism; D008855:Microscopy, Electron, Scanning
chemical_list: D019344:Lactic Acid; D007785:Lactose