The activity of β-galactosidase and lactose metabolism in Kluyveromyces lactis cultured in cheese whey as a function of growth rate

Show simple item record Ornelas, A. P. Silveira, W. B. Sampaio, F. C. Passos, F. M. L 2018-11-29T13:20:41Z 2018-11-29T13:20:41Z 2007-11-27
dc.identifier.issn 1364-5072
dc.description.abstract Kluyveromyces lactis was cultured in cheese whey permeate on both batch and continuous mode to investigate the effect of time course and growth rate on β-galactosidase activity, lactose consumption, ethanol production and protein profiles of the cells. Cheese whey was the substrate to grow K. lactis as a batch or continuous culture. In order to precise the specific growth rate for maximum β‐galactosidase activity a continuous culture was performed at five dilution (growth) rates ranging from 0·06, 0·09, 0·12, 0·18 to 0·24 h−1. The kinetics of lactose consumption and ethanol production were also evaluated. On both batch and continuous culture a respirofermentative metabolism was detected. The growth stage for maximum β‐gal activity was found to be at the transition between late exponential and entrance of stationary growth phase of batch cultures. Fractionating that transition stage in several growth rates at continuous culture a maximum β‐galactosidase activity at 0·24 h−1 was observed. Following that stage β‐gal activity undergoes a decline which does not correlate to the density of its corresponding protein band on the gel prepared from the same samples.The maximum β‐galactosidase activity per unit of cell mass was found to be 341·18 mmol ONP min−1 g−1 at a dilution rate of 0·24 h−1.The physiology of K. lactis growing in cheese whey permeate can proven useful to optimize the conversion of that substrate in biomass rich in β‐gal or in ethanol fuel. In addition to increasing the native enzyme the conditions established here can be set to increase yields of recombinant protein production based on the LAC4 promoter in K. lactis host. en
dc.format pdf pt-BR
dc.language.iso eng pt-BR
dc.publisher Journal of Applied Microbiology pt-BR
dc.relation.ispartofseries Volume 104, Issue 4, Pages 1008– 1013, April 2008 pt-BR
dc.rights Open Access pt-BR
dc.subject α-galactosidase pt-BR
dc.subject Cheese whey pt-BR
dc.subject Continous culture pt-BR
dc.subject Lacose metabolism pt-BR
dc.subject Kluyveromyces lactis pt-BR
dc.title The activity of β-galactosidase and lactose metabolism in Kluyveromyces lactis cultured in cheese whey as a function of growth rate en
dc.type Artigo pt-BR

Files in this item

This item appears in the following Collection(s)

  • Artigos [268]
    Artigos Técnico-científicos na área de Microbiologia

Show simple item record

Search DSpace


My Account