naa a22 4500 510818838 CHVBK 20180411083521.0 cr unu---uuuuu 180411e20130101xx s 000 0 eng 10.1007/s11814-012-0105-1 doi (NATIONALLICENCE)springer-10.1007/s11814-012-0105-1 Improvement of lactulose synthesis through optimization of reaction conditions with immobilized β -galactosidase [Elektronische Daten] [Yoon Song, Young Suh, Chulhwan Park, Seung Kim] Kluyveromyces lactis β-galactosidase was immobilized on silica gels using a covalent bonding method. To improve lactulose synthesis using immobilized β-galactosidase, the optimal reaction conditions, such as lactose and fructose concentrations, pH and ionic strength of the buffer, loading amount of the enzyme and temperature, were determined. Lactulose synthesis using the immobilized β-galactosidase was markedly improved after optimization of the reaction conditions. When the lactulose synthesis was carried out at 47 °C using 40% (w/v) lactose, 20% (w/v) fructose and immobilized β-galactosidase of 12 U/ml in 50 mM sodium phosphate buffer at pH 7.5, the lactulose concentration and specific productivity were 15.80 g/l and 1.32 mg/U·h, respectively. In addition, when the immobilized β-galactosidase was reused for lactulose synthesis, its catalytic activity retained 60.5% after 10 reuses. Korean Institute of Chemical Engineers, Seoul, Korea, 2012 β -Galactosidase nationallicence Lactulose nationallicence Optimization nationallicence Transgalactosylation nationallicence Immobilization nationallicence Song Yoon Department of Chemical and Biological Engineering, Korea University, 5Ga, Anam-dong, Sungbuk-gu, 136-701, Seoul, Korea aut Suh Young Department of Chemical and Biological Engineering, Korea University, 5Ga, Anam-dong, Sungbuk-gu, 136-701, Seoul, Korea aut Park Chulhwan Department of Chemical Engineering, Kwangwoon University, 447-1, Wolgye-dong, Nowon-gu, 139-701, Seoul, Korea aut Kim Seung Department of Chemical and Biological Engineering, Korea University, 5Ga, Anam-dong, Sungbuk-gu, 136-701, Seoul, Korea aut Korean Journal of Chemical Engineering Springer US; http://www.springer-ny.com 30/1(2013-01-01), 160-165 0256-1115 30:1<160 2013 30 11814 https://doi.org/10.1007/s11814-012-0105-1 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11814-012-0105-1 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Song Yoon Department of Chemical and Biological Engineering, Korea University, 5Ga, Anam-dong, Sungbuk-gu, 136-701, Seoul, Korea aut NATIONALLICENCE 700 1- Suh Young Department of Chemical and Biological Engineering, Korea University, 5Ga, Anam-dong, Sungbuk-gu, 136-701, Seoul, Korea aut NATIONALLICENCE 700 1- Park Chulhwan Department of Chemical Engineering, Kwangwoon University, 447-1, Wolgye-dong, Nowon-gu, 139-701, Seoul, Korea aut NATIONALLICENCE 700 1- Kim Seung Department of Chemical and Biological Engineering, Korea University, 5Ga, Anam-dong, Sungbuk-gu, 136-701, Seoul, Korea aut NATIONALLICENCE 773 0- Korean Journal of Chemical Engineering Springer US; http://www.springer-ny.com 30/1(2013-01-01), 160-165 0256-1115 30:1<160 2013 30 11814 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer