TY - JOUR
T1 - Immobilization of Aspergillus oryzae Β-galactosidase in an agarose matrix functionalized by four different methods and application to the synthesis of lactulose
AU - Guerrero, Cecilia
AU - Vera, Carlos
AU - Serna, Nestor
AU - Illanes, Andrés
N1 - Publisher Copyright:
© 2017 Elsevier Ltd
PY - 2017
Y1 - 2017
N2 - Aspergillus oryzae β-galactosidase was immobilized in monofunctional glyoxyl-agarose and heterofunctional supports (amino-glyoxyl, carboxy-glyoxyl and chelate-glyoxyl agarose), for obtaining highly active and stable catalysts for lactulose synthesis. Specific activities of the amino-glyoxyl agarose, carboxy-glyoxyl agarose and chelate-glyoxyl agarose derivatives were 3676, 430 and 454 IU/g biocatalyst with half-life values at 50 °C of 247, 100 and 100 h respectively. Specific activities of 3490, 2559 and 1060 IU/g were obtained for fine, standard and macro agarose respectively. High immobilization yield (39.4%) and specific activity of 7700 IU/g was obtained with amino-glyoxyl-agarose as support. The highest yields of lactulose synthesis were obtained with monofunctional glyoxyl-agarose. Selectivity of lactulose synthesis was influenced by the support functionalization: glyoxyl-agarose and amino-glyoxyl-agarose derivatives retained the selectivity of the free enzyme, while selectivity with the carboxy-glyoxyl-agarose and chelate-glyoxyl-agarose derivatives was reduced, favoring the synthesis of transgalactosylated oligosaccharides over lactulose.
AB - Aspergillus oryzae β-galactosidase was immobilized in monofunctional glyoxyl-agarose and heterofunctional supports (amino-glyoxyl, carboxy-glyoxyl and chelate-glyoxyl agarose), for obtaining highly active and stable catalysts for lactulose synthesis. Specific activities of the amino-glyoxyl agarose, carboxy-glyoxyl agarose and chelate-glyoxyl agarose derivatives were 3676, 430 and 454 IU/g biocatalyst with half-life values at 50 °C of 247, 100 and 100 h respectively. Specific activities of 3490, 2559 and 1060 IU/g were obtained for fine, standard and macro agarose respectively. High immobilization yield (39.4%) and specific activity of 7700 IU/g was obtained with amino-glyoxyl-agarose as support. The highest yields of lactulose synthesis were obtained with monofunctional glyoxyl-agarose. Selectivity of lactulose synthesis was influenced by the support functionalization: glyoxyl-agarose and amino-glyoxyl-agarose derivatives retained the selectivity of the free enzyme, while selectivity with the carboxy-glyoxyl-agarose and chelate-glyoxyl-agarose derivatives was reduced, favoring the synthesis of transgalactosylated oligosaccharides over lactulose.
KW - Agarose matrix
KW - Aspergillus oryzae
KW - Immobilization
KW - Lactulose
KW - β-Galactosidase
UR - http://www.scopus.com/inward/record.url?scp=85013078195&partnerID=8YFLogxK
U2 - 10.1016/j.biortech.2017.02.003
DO - 10.1016/j.biortech.2017.02.003
M3 - Article
C2 - 28214445
AN - SCOPUS:85013078195
VL - 232
SP - 53
EP - 63
JO - Bioresource Technology
JF - Bioresource Technology
SN - 0960-8524
ER -