TY - JOUR
T1 - A novel acid-stable, acid-active β-galactosidase potentially suited to the alleviation of lactose intolerance
AU - O'Connell, Shane
AU - Walsh, Gary
PY - 2010/3
Y1 - 2010/3
N2 - Extracellular β-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 °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 β-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 β-galactosidase was formulated, along with a neutral β-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.
AB - Extracellular β-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 °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 β-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 β-galactosidase was formulated, along with a neutral β-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.
KW - β-galactosidase
KW - Aspergillus niger van Tiegh
KW - Lactase
KW - Lactose intolerance
KW - Two-segment capsule
UR - http://www.scopus.com/inward/record.url?scp=77249089742&partnerID=8YFLogxK
U2 - 10.1007/s00253-009-2270-7
DO - 10.1007/s00253-009-2270-7
M3 - Article
C2 - 19806354
AN - SCOPUS:77249089742
SN - 0175-7598
VL - 86
SP - 517
EP - 524
JO - Applied Microbiology and Biotechnology
JF - Applied Microbiology and Biotechnology
IS - 2
ER -