A novel acid-stable, acid-active beta-galactosidase potentially suited to the alleviation of lactose intolerance.
Appl Microbiol Biotechnol
; 86(2): 517-24, 2010 Mar.
Article
em En
| MEDLINE
| ID: mdl-19806354
ABSTRACT
Extracellular beta-galactosidase produced by a strain of Aspergillus niger van Tiegh was purified to homogeneity using a combination of gel filtration, ion-exchange, chromatofocusing, and hydrophobic interaction chromatographies. The enzyme displayed a temperature optimum of 65 degrees C and a low pH optimum of between 2.0 and 4.0. The monomeric glycosylated enzyme displayed a molecular mass of 129 kDa and an isoelectric point of 4.7. Protein database similarity searching using mass spectrometry-derived sequence data indicate that the enzyme shares homology with a previously sequenced A. niger beta-galactosidase. Unlike currently commercialised products, the enzyme displayed a high level of stability when exposed to simulated gastric conditions in vitro, retaining 68+/-2% of original activity levels. This acid-stable, acid-active beta-galactosidase was formulated, along with a neutral beta-galactosidase from Kluyveromyces marxianus DSM5418, in a novel two-segment capsule system designed to ensure delivery of enzymes of appropriate physicochemical properties to both stomach and small intestine. When subjected to simulated full digestive tract conditions, the twin lactase-containing capsule hydrolyzed, per unit activity, some 3.5-fold more lactose than did the commercial supplemental enzyme. The acid-stable, acid-active enzyme, along with the novel two-segment delivery system, may prove beneficial in the more effective treatment of lactose intolerance.
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1
Base de dados:
MEDLINE
Assunto principal:
Aspergillus niger
/
Proteínas Fúngicas
/
Beta-Galactosidase
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article