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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.


Adsorption equilibria of Fe3O4-CS-THP-immobilized β-galactosidase. 0.5 g of Fe3O4-CS-THP was added to 4 mL of β-galactosidase solution at various concentrations, and enzyme immobilization was allowed to proceed with mild shaking at 25 °C for 2 h. The particles were then collected with a permanent magnet and washed with distilled water thrice. The resulting immobilized enzyme was stored in the 0.1 M sodium acetate buffer (pH 6.0) at 4 °C. The data are averaged from three samples. (Δ) Activity of immobilized enzyme; (▲) Percent of enzyme activity retained; (□) Immobilized protein per gram of Fe3O4-CS-THP nanoparticles.
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ijms-16-12499-f001: Adsorption equilibria of Fe3O4-CS-THP-immobilized β-galactosidase. 0.5 g of Fe3O4-CS-THP was added to 4 mL of β-galactosidase solution at various concentrations, and enzyme immobilization was allowed to proceed with mild shaking at 25 °C for 2 h. The particles were then collected with a permanent magnet and washed with distilled water thrice. The resulting immobilized enzyme was stored in the 0.1 M sodium acetate buffer (pH 6.0) at 4 °C. The data are averaged from three samples. (Δ) Activity of immobilized enzyme; (▲) Percent of enzyme activity retained; (□) Immobilized protein per gram of Fe3O4-CS-THP nanoparticles.

Mentions: Fe3O4-CS-THP and Fe3O4-CS nanoparticles were used for enzyme immobilization at various enzyme concentrations. Figure 1 and Figure 2 show the absorption equilibria for different initial enzyme concentrations versus the activities of the immobilized enzyme, and the percentage of the adsorbed enzyme activity retained on the Fe3O4-CS-THP and Fe3O4-CS nanoparticles, respectively. Interestingly, the Fe3O4-CS nanoparticles showed better enzyme activity retention than the Fe3O4-CS-THP nanoparticles. The enzyme activity retained after immobilization ranged from 70% to 23% for the Fe3O4-CS-THP nanoparticles (Figure 1), and from 85% to 40% for the Fe3O4-CS nanoparticles (Figure 2). For subsequent experiments, the immobilized enzyme was prepared with an initial enzyme concentration of 20 mg·mL−1 for Fe3O4-CS-THP and 10 mg·mL−1 for Fe3O4-CS.


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)

Adsorption equilibria of Fe3O4-CS-THP-immobilized β-galactosidase. 0.5 g of Fe3O4-CS-THP was added to 4 mL of β-galactosidase solution at various concentrations, and enzyme immobilization was allowed to proceed with mild shaking at 25 °C for 2 h. The particles were then collected with a permanent magnet and washed with distilled water thrice. The resulting immobilized enzyme was stored in the 0.1 M sodium acetate buffer (pH 6.0) at 4 °C. The data are averaged from three samples. (Δ) Activity of immobilized enzyme; (▲) Percent of enzyme activity retained; (□) Immobilized protein per gram of Fe3O4-CS-THP nanoparticles.
© Copyright Policy
Related In: Results  -  Collection

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

ijms-16-12499-f001: Adsorption equilibria of Fe3O4-CS-THP-immobilized β-galactosidase. 0.5 g of Fe3O4-CS-THP was added to 4 mL of β-galactosidase solution at various concentrations, and enzyme immobilization was allowed to proceed with mild shaking at 25 °C for 2 h. The particles were then collected with a permanent magnet and washed with distilled water thrice. The resulting immobilized enzyme was stored in the 0.1 M sodium acetate buffer (pH 6.0) at 4 °C. The data are averaged from three samples. (Δ) Activity of immobilized enzyme; (▲) Percent of enzyme activity retained; (□) Immobilized protein per gram of Fe3O4-CS-THP nanoparticles.
Mentions: Fe3O4-CS-THP and Fe3O4-CS nanoparticles were used for enzyme immobilization at various enzyme concentrations. Figure 1 and Figure 2 show the absorption equilibria for different initial enzyme concentrations versus the activities of the immobilized enzyme, and the percentage of the adsorbed enzyme activity retained on the Fe3O4-CS-THP and Fe3O4-CS nanoparticles, respectively. Interestingly, the Fe3O4-CS nanoparticles showed better enzyme activity retention than the Fe3O4-CS-THP nanoparticles. The enzyme activity retained after immobilization ranged from 70% to 23% for the Fe3O4-CS-THP nanoparticles (Figure 1), and from 85% to 40% for the Fe3O4-CS nanoparticles (Figure 2). For subsequent experiments, the immobilized enzyme was prepared with an initial enzyme concentration of 20 mg·mL−1 for Fe3O4-CS-THP and 10 mg·mL−1 for Fe3O4-CS.

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.