Influence of Silica-Derived Nano-Supporters on Cellobiase After Immobilization

Wang, Peng; Hu, Xiaoke; Cook, Sean; Hwang, Huey‐Min

doi:10.1007/s12010-008-8321-1

Cited by 28 publications

(16 citation statements)

References 24 publications

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“…Calsavara et al (2001) reported that t ½ of free and immobilized cellobiase at 65 ºC were 2.1 and 21.3 h, respectively. This is probably due to the formation of multiple covalent bonds between β-glucosidase and the support that reduce conformational flexibility and thermal vibration, thus preventing the immobilized protein from unfolding and denaturing (Mateo et al, 2000;Wang et al, 2009;Figueira et al, 2011). The deactivation rate constant at 65 ºC for the immobilized β-glucosidase is 9.5x10 -3 / min, which is lower than that of the free form (12.53x10 -3 / min).…”

Section: Thermal Stabilitymentioning

confidence: 97%

Biochemical studies on immobilized fungal β-glucosidase

Ahmed

El-Shayeb

Hashem

et al. 2013

Braz. J. Chem. Eng.

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-β-Glucosidase from Aspergillus niger was immobilized on sponge by covalent binding through a spacer group (glutaraldehyde). Sponge-immobilized enzyme had the highest immobilization yield (95.67%) and retained 63.66% of the original activity exhibited by the free enzyme. The optimum pH of the immobilized enzyme remains almost the same as for the free enzyme (pH 4.0). The optimum temperature for β-glucosidase activity was increased by 10 ºC after immobilization. The activation energy (E a ) of the immobilized β-glucosidase was lower than the free enzyme (3.34 and 4.55 kcal/mol), respectively. Immobilized β-glucosidase exhibited great thermal stability and retained all the initial activity after incubation at 55 ºC for 2 h; however, the free enzyme retained 89.25% under the same condition. The calculated half-life (t ½ ) value of heat inactivation of immobilized enzyme at 60, 65 and 70 ºC was 213.62, 72.95 and 56.80 min, respectively, whereas at these temperatures the free enzyme was less stable (half-life of 200.0, 55.31 and 49.5 min, respectively). The deactivation rate constant at 65 ºC for the immobilized β-glucosidase is 9.5x10 -3 / min, which was lower than that of the free form (12.53x10 -3 / min). The immobilization process improved the pH stability of the enzyme (immobilized and free enzyme retained 69.35 and 39.86%, respectively, of their initial activity after 45 min at pH 7.5). The effect of some chemical substances on the activity of the immobilized and free β-glucosidase has been investigated. In the presence of sodium dodecyl sulfate (SDS) and p-chloromercuri benzoate (p-CMB) the immobilized enzyme retained 36.13 and 45.34%, respectively, of the initial activity, which is higher than that of free enzyme (13.71 and 1.61%, respectively). The Michaelis constant (K m ) value of the free enzyme was 40.0 mM, while the apparent K m value for the immobilized enzyme was 46.51 mM. The maximum reaction rate (v max ) of immobilized β-glucosidase was smaller than that of the free enzyme by 7.69%. Sponge-immobilized β-glucosidase was repeatedly used to hydrolyze cellobiose (5 and 8 cycles with retained activity of 67.32 and 51.04%, respectively).

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Section: Thermal Stabilitymentioning

confidence: 97%

Biochemical studies on immobilized fungal β-glucosidase

Ahmed

El-Shayeb

Hashem

et al. 2013

Braz. J. Chem. Eng.

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“…ey have been used extensively for various applications including photothermal therapy [19], photodynamic therapy [20,21], magnetic resonance imaging [22], peptide delivery [23], and gene delivery [24,25]. SiNPs are "tunable" because they are easily modi�ed with functional groups like -COOH and -NH 2 , which allows conjugation with a target moiety for targeted delivery and, therefore, promotes better therapies as well as prognosis [26,27].…”

Section: Introductionmentioning

confidence: 99%

Amino-Functionalized Silica Nanoparticles: In Vitro Evaluation for Targeted Delivery and Therapy of Pancreatic Cancer

Kardys

Bharali

Mousa

2013

Journal of Nanotechnology

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We report a method of synthesis and optimization of amino-functionalized silica nanoparticles (SiNPs) and their in vitro evaluation as targeted delivery vehicles for the potential treatment of pancreatic cancer. SiNPs can efficiently encapsulate doxorubicin and can be attached to a targeting moiety such as anti-Claudin-4 (CLN4). e preferential uptake in pancreatic cancer cells, where CLN4 is overexpressed, of SiNPs when conjugated to CLN4 antibody (compared to nonconjugated SiNPs) was con�rmed by confocal microscopy. SiNPs encapsulating doxorubicin had greater efficacy in MTT assays than free doxorubicin, and when conjugated to CLN4, the efficacy was dramatically increased (at 1 M). No apparent carrier toxicity was observed when void SiNPs were used. SiNPs carrying a chemotherapeutic drug have the potential to be used as a targeted therapy for lethal cancers, such as pancreatic cancer. Also, incorporation of �uorescent probes in these SiNPs creates the possibility of their use as an imaging probe for diagnostic purposes.

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“…However in other reports, immobilization of b-glucosidase on SiO 2 nanoparticles caused an increase in both the K m (2.5 mM for free and 3.8 mM for immobilized) and V max (3028 U/ mg protein to 3347 U/mg protein) of the enzyme (Singh et al 2011). The K m and V max values were 27.1 mM and 3.41 mmol/mg/min for free glucose oxidase while 14.6 mM and 0.116 mmol/mg/min for glucose oxidase immobilized on aminated-CoFe 2 O 4 /SiO 2 magnetic nanoparticles (Wang et al 2009). Similar results were found by Georgelin et al (2010) with increase K m (from 7.6 mM to 8.6 mM) and decreased k cat (from 69 to 34 s -1 ) after immobilization of b-glucosidase on functionalized cFe 2 O 3 @ SiO 2 core-shell magnetic nanoparticles.…”

Section: Kinetic Parameters Of Free and Immobilized B-glucosidasementioning

confidence: 96%

Immobilization of β-glucosidase onto silicon oxide nanoparticles and augment of phenolics in sugarcane juice

2016

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Purified b-glucosidase was immobilized on SiO 2 nanoparticles with 52 % efficiency and 14.1 % yield. It had a temperature optima at 60°C and pH optima of 5.0. Immobilized enzyme was fairly stable at 60-70°C. After immobilization, the K m value of b-glucosidase for p-nitrophenyl-b-D-glucopyranoside (pNPG) increased from 0.9 to 1.074 mM and V max decreased from 3.5 to 1.513 U/mg. The immobilized enzyme showed improved storage stability at temperature 4 and 25°C and was reusable for up to ten cycles with 70 % residual activity in pNPG and 60 % residual activity in sugarcane juice treatment. Sugarcane juice density, viscosity; surface tension etc. changed after treatment with immobilized b-glucosidase. b-Glucosidase treated sugarcane juice showed higher phenolics than untreated sugarcane juice. Caffeic acid which was absent in juice, was detected in b-glucosidase treated juice at a concentration of about 1 mg/L.

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Influence of Silica-Derived Nano-Supporters on Cellobiase After Immobilization

Cited by 28 publications

References 24 publications

Biochemical studies on immobilized fungal β-glucosidase

Biochemical studies on immobilized fungal β-glucosidase

Amino-Functionalized Silica Nanoparticles: In Vitro Evaluation for Targeted Delivery and Therapy of Pancreatic Cancer

Immobilization of β-glucosidase onto silicon oxide nanoparticles and augment of phenolics in sugarcane juice

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