scholarly journals ENCAPSULATION OF HORSERADISH PEROXIDASE-GLUCOSE OXIDASE (HRP-GOx) IN SILICA AQUAGEL SYNTHESIZED FROM RICE HULL ASH FOR ENZYMATIC REACTION OF GLUCOSE

2010 ◽  
Vol 8 (2) ◽  
pp. 169-176
Author(s):  
Nuryono Nuryono ◽  
Narsito Narsito ◽  
Endang Astuti
Keyword(s):  
Horseradish Peroxidase ◽  
Enzymatic Activity ◽  
Glucose Oxidase ◽  
Sol Gel ◽  
Enzymatic Reaction ◽  
Weight Ratio ◽  
Sodium Concentration ◽  
Rice Hull ◽  
Rice Hull Ash ◽  
Activity Decrease

In recent years, the sol-gel technique has attracted increasing interest as a unique approach to immobilize biomolecules for bioanalytical applications as well as biochemical and biophysical studies. In this research, encapsulation of Horseradish peroxidase-Glucose oxidase (HRP-GOx) enzymes in silica aquagel from rice hull ash by sol-gel process has been carried out. In addition, the effect of several parameters (weight ratio of HRP to GOx, pH, temperature, sodium ion concentration) on enzyme activity was studied, as well. Rice hull ash, which was produced by ashing at 700 °C, was extracted it's silika by NaOH solution 1 M at 100 °C for two hours to produce sodium silikate (Na2SiO3) solution. The Na2SiO3 solution with pH of 13 was added with a strong cation exchanger resin, to produce sol solution with the pH of 4. Encapsulation was emphasized by mixing sol solution and phosphate buffer pH 7 containing HRP-GOx solution at volume ratio of buffer to sol solution 1:5. The mixture was transferred into 96-microwell plate and was aged for 24 hours. Enzymatic reaction was carried out by adding chromogenic solution of phenol and 4-aminoantipyrine (4-AAP) and b-D-glucose solution (as substrate) into the microwell. Enzymatic activity was examined by measuring absorbance of product solution at 490 nm with ELISA reader. Result of enzymatic activity for encapsulated enzymes (SGE) was compared to that for free enzymes (EB). Results showed that at the investigated condition, HRP-GOx enzymes gave high activity at weight ratio of HRP to GOx 10:1 and pH 7 for both SGE and EB. Encapsulation caused the enzymes activity decrease to 53.0±0.2 %. However, SGE was observed to be more stable on pH and temperature changes than EB. Study on the effect of sodium concentration showed that the increase of sodium concentration from 0.10 to 0.37 M decreased the enzymatic activity to 56±0.2%. Reusability test showed that the synthesized SGE was reusable with activity decrease of 60% within 23 days.   Keywords: rice hull ash, encapsulation, aquagel, horseradish peroxidase, glucose oxidase

scholarly journals Dynamic monitoring of a bi-enzymatic reaction at a single biomimetic giant vesicle

The Analyst ◽  
2020 ◽  
Vol 145 (24) ◽  
pp. 7922-7931
Author(s):  
Pauline Lefrançois ◽  
Bertrand Goudeau ◽  
Stéphane Arbault
Keyword(s):  
Confocal Microscopy ◽  
Horseradish Peroxidase ◽  
Glucose Oxidase ◽  
Enzymatic Reaction ◽  
Dynamic Monitoring ◽  
Giant Unilamellar Vesicles ◽  
Unilamellar Vesicles ◽  
Giant Vesicle ◽  
Micro Reactors

Giant unilamellar vesicles were used as individual biomimetic micro-reactors wherein a model bi-enzymatic reaction involving a glucose oxidase (GOx) and horseradish peroxidase (HRP) was monitored by confocal microscopy.

Enzymatic activity of glucose oxidase encapsulated in transparent glass by the sol-gel method

1992 ◽  
Vol 4 (3) ◽  
pp. 495-497 ◽  
Author(s):  
Stacey A. Yamanaka ◽  
Fumito Nishida ◽  
Lisa M. Ellerby ◽  
Clinton R. Nishida ◽  
Bruce Dunn ◽  
...  
Keyword(s):  
Enzymatic Activity ◽  
Glucose Oxidase ◽  
Sol Gel ◽  
Transparent Glass ◽  
Gel Method ◽  
Sol Gel Method

Prospects of Use and Impact of Nanoparticles on the Properties of High-Strength Concrete

2014 ◽  
Vol 584-586 ◽  
pp. 1416-1424 ◽  
Author(s):  
Artem Frolov ◽  
Ludmila Chumadova ◽  
Artemiy Cherkashin ◽  
Luka Akimov
Keyword(s):  
Iron Hydroxide ◽  
Sol Gel ◽  
Ferric Hydroxide ◽  
High Strength ◽  
Rice Hull ◽  
Nanosized Particles ◽  
Rice Hull Ash ◽  
Huge Number ◽  
The Cost ◽  
Cost Of Construction

The basic properties of concrete can dramatically improve due to the unique structure of the nanosized particles. Namely, strength, frost resistance, fire resistance, corrosion resistance are increased, density and permeability are reduced; plasticity and water absorption are regulated. Despite of the huge number of advantages of nanomodified concrete, analysis of the use of nanoparticles shows that they are used quite seldom, as it requires a large cash outlay. It is not always profitable to use such additives. This article discusses some additives: magnesium nanoshpinel, microspheres, rice hull ash and metakaolin, astralenes, ferric hydroxide sol, carbon nanotubes, silica fume, nanosilica, MB-01, combined modifiers, based on iron hydroxide sol and silica sol. As well in this article sol-gel method as an additive in concrete is considered. The analysis shows that the use of nanosized particles can reduce a large amount of cement. As an addition, savings of the use are seen in reducing the cost of construction due to the low density with high strength. Accurate material consumption and maximum use of advantages of nanomodified concrete provide great prospects of implementation of this material in construction.

Biodegradable Corn Starch/Silica Nanocomposite Sheets for Food Packaging Applications

2017 ◽  
Vol 894 ◽  
pp. 66-71
Author(s):  
Adeliza A. Dorado ◽  
Engelbert K. Peralta ◽  
Ernesto V. Carpio ◽  
Ernesto P. Lozada ◽  
Arnold R. Elepaño
Keyword(s):  
Food Packaging ◽  
Corn Starch ◽  
Sol Gel ◽  
Extraction Yield ◽  
Rice Hull ◽  
Rice Hull Ash ◽  
Environment Friendly ◽  
Elongation At Break ◽  
Force Microscopy ◽  
Atomic Force

The use of nanomaterials for food packaging has been steadily increasing globally and is already a billion dollar industry. There is also growing interests in developing safe and environment-friendly packaging materials. This study developed a corn starch-based nanocomposite sheet using nanosilica from recycled biodegradable rice hull ash using sol-gel method. The nanosilica extraction yield was 80.41% with purity of about 99%. The sizes of extracted silica particles and agglomerated nanosilica are 6.33 ± 1.62 nm (using atomic force microscopy) and 41.67 to 72.92 nm (using scanning electron microscope), respectively. The specific surface area of the nanosilica was 108.54 m2/g with pore radius of 9.07 nm. Nanocomposite sheets from mixture of nanosilica and corn starch matrix, were produced using three different extrusion temperature profiles and three different nanosilica concentration of 1%, 2% and 3%. Addition of nanosilica improved the mechanical properties of the nanocomposite sheets. Tensile strength increased, while elongation at break decreased. Nanocomposite sheets with nanosilica displayed improved water resistance while those without nanosilica disintegrated within two hours of immersion in distilled water at 25 °C.

Adsorption of gold(III) on ionic imprinted amino-silica hybrid prepared from rice hull ash

2012 ◽  
Vol 85 (1) ◽  
pp. 211-223 ◽  
Author(s):  
Satya Candra Wibawa Sakti ◽  
Dwi Siswanta ◽  
Keyword(s):  
Aqueous Solution ◽  
Contact Time ◽  
Sol Gel ◽  
Ion Concentration ◽  
Rice Hull ◽  
Rice Hull Ash ◽  
Batch System ◽  
Pseudo Second Order ◽  
Gel Technique ◽  
Silica Hybrid

In this research, the adsorption of Au(III) ion on ionic imprinted amino-silica hybrid (Im-ASH) in aqueous solution has been studied. Im-ASH was synthesized via sol-gel technique using a solution of sodium silicate (Na2SiO3) from rice hull ash (RHA) as the precursor and Au(III) ion as the template. Adsorption was carried out in a batch system with variation of pH, contact time, and Au(III) ion concentration. The selectivity of adsorbent toward Au(III) was examined in the presence of Cu(II) ion. The result of the kinetic study demonstrated that the adsorption of Au(III) ion followed pseudo-second order. The optimum adsorption of Au(III) on Im-ASH and non-Im-ASH was obtained at pH of 3.0. Im-ASH was twice as selective toward Au(III) ion than ASH was.

scholarly journals ADSORPTION OF Mg(II) AND Ca(II) ON DISULFONATO-SILICA HYBRID

2012 ◽  
Vol 12 (3) ◽  
pp. 223-228 ◽  
Author(s):  
Choiril Azmiyawati ◽  
Nuryono Nuryono ◽  
Narsito Narsito
Keyword(s):  
Sodium Silicate ◽  
Sol Gel ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Disulfonic Acid ◽  
Rice Hull ◽  
Rice Hull Ash ◽  
Solution Ph ◽  
System Solution ◽  
Silica Hybrid

Adsorption of Mg(II) and Ca(II) on disulfonato-silica hybrid (DSSH) in the aqueous solution has been studied. The hybrid was synthesized by sol-gel process with sodium silicate solution from rice hull ash, chloroprophyltrimethoxysilane (CTS) and 4-amino-5-hydroxy-naphtalene-2,7-disulfonic acid monosodium salt (ANSNa) as silica source, cross linker and active group, respectively. Sodium silicate solution was reacted with CTS and ANSNa that were added dropwise. Adsorption of magnesium and calcium ions on DSSH was carried out in a batch system. Solution pH significantly affected magnesium and calcium adsorption and the optimum condition was obtained at pH = 6. The synthesized DSSH showed a high adsorption capacity of 0.0844 mmol/g and 0.1442 mmol/g for Mg(II) and Ca(II), respectively. The adsorption isotherm obtained with Langmuir isotherm model gives the negative values of ΔG°, i.e. -23.334 kJ/mol and -22.757 kJ/mol for Mg(II) and Ca(II), respectively, indicating the spontaneous process of adsorption. Kinetic studies showed that the adsorption of Mg(II) and Ca(II) ions onto HDSS follows the pseudo-second-order kinetics.

scholarly journals Synthesis of SrO.SiO2 Catalyst and Its Application in the Transesterification Reactions of Soybean Oil

2017 ◽  
Vol 12 (2) ◽  
pp. 299 ◽  
Author(s):  
Nuni Widiarti ◽  
Lisa Amalia Suryana ◽  
Nanik Wijayati ◽  
Endah Fitriani Rahayu ◽  
Harjito Harjito ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Soybean Oil ◽  
Sol Gel ◽  
Reaction Engineering ◽  
Rice Hull ◽  
Synthesis And Characterization ◽  
Rice Hull Ash ◽  
Diffraction Angle ◽  
Gel Technique

The synthesis and characterization of SrO.SiO2 were carried out. The rice hull ash was utilized as a source for SiO2. The SrO.SiO2 was prepared by sol-gel technique, and the ratios of SrO:SiO2 were      varied as 0:1, 1:0, 3:2, 2:4, and 2:7. The sol-gel was calcined at 800 oC for 4 hours. The result was    characterized using XRD and FTIR. The diffraction pattern shows that the diffraction angle was shifted, and the intensity of the main peaks was increased. This research indicated that the            crystallinity of SrO was improved at the higher SiO content. Further, a new peak was observed in the IR spectra at a wavenumber of 900 cm-1 indicating the appearance of new functional groups of the SrO.SiO2. The catalytic activity of SrO.SiO2 on transesterification reaction was optimized. The optimum condition was obtained at SrO.SiO2 of 2:7, reaction time of 30 minutes, reaction temperature of 65 oC, the amount of catalyst of 1 % w/v of reactants, and the biodiesel yield of 96.66 %. Copyright © 2017 BCREC Group. All rights reservedReceived: 11st November 2016; Revised: 28th February 2017; Accepted: 28th February 2017How to Cite: Widiarti, N., Suryana, L.A., Wijayati, N., Rahayu, E.F., Harjito, H., Wardhana, S.B., Prasetyoko, D., Suprapto, S. (2017). Synthesis of SrO.SiO2 Catalyst and Its Application in the Transesterification Reactions of Soybean Oil. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (2): 299-305 (doi:10.9767/bcrec.12.2.804.299-305)Permalink/DOI: http://dx.doi.org/10.9767/bcrec.12.2.804.299-305 

Water filtration using rice hull ash

Waterlines ◽  
1983 ◽  
Vol 2 (2) ◽  
pp. 21-23 ◽  
Author(s):  
Barnes ◽  
Mampitiyarachichi
Keyword(s):  
Water Filtration ◽  
Rice Hull ◽  
Rice Hull Ash
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