title: Use of continuous lactose fermentation for ethanol production by Kluveromyces marxianus for verification and extension of a biochemically structured model.
abstract: A biochemically structured model has been developed to describe the continuous fermentation of lactose to ethanol by Kluveromyces marxianus and allowed metabolic coefficients to be determined. Anaerobic lactose-limited chemostat fermentations at different dilution rates (0.02-0.35h(-1)) were performed. Species specific rates of consumption/formation, as well as yield coefficients were determined. Ethanol yield (0.655 C-mol ethanol(∗)C-mol lactose(-1)) was as high as 98% of theoretical. The modeling procedure allowed calculation of maintenance coefficients for lactose consumption and ethanol production of m(s)=0.6029 and m(e)=0.4218 (C-mol) and (C-molh)(-1), respectively. True yield coefficients for biomass, ethanol and glycerol production were calculated to be Y(true)(sx)=0.114, Y(true)(ex)=0.192 and Y(sg)=2.250 (C-mol) and (C-mol)(-1), respectively. Model calculated maintenance and true yield coefficients agreed very closely with those determined by regressions of the experimental data. The model developed provides a solid basis for the rational design of optimised fermentation of cheese whey.
authors: Novozymes A/S, Solid Products Development, DK-2880 Bagsvaerd, Denmark. scse@novozymes.com
authors: S
authors: S
authors: Sansonetti
authors: T J
authors: TJ
authors: Hobley
authors: S
authors: S
authors: Curcio
authors: J
authors: J
authors: Villadsen
authors: G
authors: G
authors: Sin
mesh_terms: D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D007716:Kluyveromyces / Q000378:metabolism*; D007785:Lactose / Q000378:metabolism*; D008954:Models, Biological
chemical_list: D000431:Ethanol; D007785:Lactose