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Production of Galactooligosaccharides Using β-Galactosidase Immobilized on Chitosan-Coated Magnetic Nanoparticles with Tris(hydroxymethyl)phosphine as an Optional Coupling Agent.

Chen SC, Duan KJ - Int J Mol Sci (2015)

Bottom Line: However, activity retention of batchwise reactions was similar for both immobilized systems.All the three enzyme systems produced GOS compound with similar concentration profiles, with a maximum GOS yield of 50.5% from 36% (w · v(-1)) lactose on a dry weight basis.The chitosan-coated magnetic Fe3O4 nanoparticles can be regenerated using a desorption/re-adsorption process described in this study.

View Article: PubMed Central - PubMed

Affiliation: Department of Bioengineering, Tatung University, Taipei 104, Taiwan. monica94707@yahoo.com.tw.

ABSTRACT
β-Galactosidase was immobilized on chitosan-coated magnetic Fe3O4 nanoparticles and was used to produce galactooligosaccharides (GOS) from lactose. Immobilized enzyme was prepared with or without the coupling agent, tris(hydroxymethyl)phosphine (THP). The two immobilized systems and the free enzyme achieved their maximum activity at pH 6.0 with an optimal temperature of 50 °C. The immobilized enzymes showed higher activities at a wider range of temperatures and pH. Furthermore, the immobilized enzyme coupled with THP showed higher thermal stability than that without THP. However, activity retention of batchwise reactions was similar for both immobilized systems. All the three enzyme systems produced GOS compound with similar concentration profiles, with a maximum GOS yield of 50.5% from 36% (w · v(-1)) lactose on a dry weight basis. The chitosan-coated magnetic Fe3O4 nanoparticles can be regenerated using a desorption/re-adsorption process described in this study.

No MeSH data available.


Batchwise reactions of immobilized enzyme at 45 °C. Fe3O4-CS- or Fe3O4-CS-THP-immobilized enzymes (0.5 g) was added to 50 mL of 36% (w·v−1) lactose at pH 6.0 in a 500 mL Erlenmeyer flask. The solution was incubated 45 °C on an orbital shaker bath of 200 rpm and the lactose solution was replaced every 24 h. The immobilized enzyme was recovered everyday by applying a magnetic field and the residual activity was measured by the standard assay. The procedure was repeated for 9 days. The activity at beginning of the experiments was set as 100%. The data are averaged from three samples. (●) Fe3O4-CS-immobilized enzyme; (○) Fe3O4-CS-THP-immobilized enzyme.
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ijms-16-12499-f006: Batchwise reactions of immobilized enzyme at 45 °C. Fe3O4-CS- or Fe3O4-CS-THP-immobilized enzymes (0.5 g) was added to 50 mL of 36% (w·v−1) lactose at pH 6.0 in a 500 mL Erlenmeyer flask. The solution was incubated 45 °C on an orbital shaker bath of 200 rpm and the lactose solution was replaced every 24 h. The immobilized enzyme was recovered everyday by applying a magnetic field and the residual activity was measured by the standard assay. The procedure was repeated for 9 days. The activity at beginning of the experiments was set as 100%. The data are averaged from three samples. (●) Fe3O4-CS-immobilized enzyme; (○) Fe3O4-CS-THP-immobilized enzyme.

Mentions: In batchwise reactions, enzymes may be detached from the surface of the nanoparticles while being shaken in the flask due to abrasion by the shear forces of the substrate solution. The detached enzyme would be lost when the nanoparticles were retrieved and washed and a new batch of substrate solution added. Therefore, it is important to compare the enzyme retention abilities of the immobilization systems. As shown in Figure 6, in batchwise reactions, the residual activities of the Fe3O4-CS-THP- and the Fe3O4-CS-immobilized enzymes were 50.9% and 47.3%, respectively, after incubation at 45 °C for 4 days (Figure 6). Thus, the two systems showed similar enzyme retention abilities.


Production of Galactooligosaccharides Using β-Galactosidase Immobilized on Chitosan-Coated Magnetic Nanoparticles with Tris(hydroxymethyl)phosphine as an Optional Coupling Agent.

Chen SC, Duan KJ - Int J Mol Sci (2015)

Batchwise reactions of immobilized enzyme at 45 °C. Fe3O4-CS- or Fe3O4-CS-THP-immobilized enzymes (0.5 g) was added to 50 mL of 36% (w·v−1) lactose at pH 6.0 in a 500 mL Erlenmeyer flask. The solution was incubated 45 °C on an orbital shaker bath of 200 rpm and the lactose solution was replaced every 24 h. The immobilized enzyme was recovered everyday by applying a magnetic field and the residual activity was measured by the standard assay. The procedure was repeated for 9 days. The activity at beginning of the experiments was set as 100%. The data are averaged from three samples. (●) Fe3O4-CS-immobilized enzyme; (○) Fe3O4-CS-THP-immobilized enzyme.
© Copyright Policy
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4490457&req=5

ijms-16-12499-f006: Batchwise reactions of immobilized enzyme at 45 °C. Fe3O4-CS- or Fe3O4-CS-THP-immobilized enzymes (0.5 g) was added to 50 mL of 36% (w·v−1) lactose at pH 6.0 in a 500 mL Erlenmeyer flask. The solution was incubated 45 °C on an orbital shaker bath of 200 rpm and the lactose solution was replaced every 24 h. The immobilized enzyme was recovered everyday by applying a magnetic field and the residual activity was measured by the standard assay. The procedure was repeated for 9 days. The activity at beginning of the experiments was set as 100%. The data are averaged from three samples. (●) Fe3O4-CS-immobilized enzyme; (○) Fe3O4-CS-THP-immobilized enzyme.
Mentions: In batchwise reactions, enzymes may be detached from the surface of the nanoparticles while being shaken in the flask due to abrasion by the shear forces of the substrate solution. The detached enzyme would be lost when the nanoparticles were retrieved and washed and a new batch of substrate solution added. Therefore, it is important to compare the enzyme retention abilities of the immobilization systems. As shown in Figure 6, in batchwise reactions, the residual activities of the Fe3O4-CS-THP- and the Fe3O4-CS-immobilized enzymes were 50.9% and 47.3%, respectively, after incubation at 45 °C for 4 days (Figure 6). Thus, the two systems showed similar enzyme retention abilities.

Bottom Line: However, activity retention of batchwise reactions was similar for both immobilized systems.All the three enzyme systems produced GOS compound with similar concentration profiles, with a maximum GOS yield of 50.5% from 36% (w · v(-1)) lactose on a dry weight basis.The chitosan-coated magnetic Fe3O4 nanoparticles can be regenerated using a desorption/re-adsorption process described in this study.

View Article: PubMed Central - PubMed

Affiliation: Department of Bioengineering, Tatung University, Taipei 104, Taiwan. monica94707@yahoo.com.tw.

ABSTRACT
β-Galactosidase was immobilized on chitosan-coated magnetic Fe3O4 nanoparticles and was used to produce galactooligosaccharides (GOS) from lactose. Immobilized enzyme was prepared with or without the coupling agent, tris(hydroxymethyl)phosphine (THP). The two immobilized systems and the free enzyme achieved their maximum activity at pH 6.0 with an optimal temperature of 50 °C. The immobilized enzymes showed higher activities at a wider range of temperatures and pH. Furthermore, the immobilized enzyme coupled with THP showed higher thermal stability than that without THP. However, activity retention of batchwise reactions was similar for both immobilized systems. All the three enzyme systems produced GOS compound with similar concentration profiles, with a maximum GOS yield of 50.5% from 36% (w · v(-1)) lactose on a dry weight basis. The chitosan-coated magnetic Fe3O4 nanoparticles can be regenerated using a desorption/re-adsorption process described in this study.

No MeSH data available.