scholarly journals α-Amylase immobilization on amidoximated acrylic microfibres activated by cyanuric chloride

2018 ◽  
Vol 5 (11) ◽  
pp. 172164 ◽  
Author(s):  
Yaaser Q. Almulaiky ◽  
Faisal M. Aqlan ◽  
Musab Aldhahri ◽  
Mohammed Baeshen ◽  
Tariq Jamal Khan ◽  
...  
Keyword(s):  
Heavy Metal Ions ◽  
Immobilized Enzyme ◽  
Industrial Applications ◽  
Cyanuric Chloride ◽  
Soluble Form ◽  
Free Form ◽  
Maximum Efficiency ◽  
Initial Activity ◽  
Acrylic Fabric ◽  
Scanning Electron

Enzyme immobilization is one of the most important techniques for industrial applications. It makes the immobilized enzyme more stable and advantageous than the free form in different aspects. α-Amylase was immobilized on 4% cyanuric chloride-activated amidoximated acrylic fabric at pH 7.0 with (79%) maximum efficiency. A field emission scanning electron microscope and Fourier transform infrared were used to confirm the immobilization process. Even after being recycled 10 times, the immobilized enzyme lost just 28% of its initial activity. Owing to immobilization, the pH of the soluble α-amylase was shifted from 6.0 to 6.5. The immobilized α-amylases showed thermal stability at 60°C, and became more resistant to heavy metal ions. The k m values of the immobilized and soluble α-amylases were 9.6 and 3.8 mg starch ml −1 , respectively. In conclusion, this method shows that the immobilized α-amylase proved to be more efficient than its soluble form, and hence could be used during saccharification of starch.

α-Amylase Aspergillus oryzae Immobilized on Modified Expanded Perlite

2014 ◽  
Vol 12 (1) ◽  
pp. 587-596 ◽  
Author(s):  
J. Rodriguez ◽  
F. Soria ◽  
H. Geronazzo ◽  
H. Destefanis
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Aspergillus Oryzae ◽  
Immobilized Enzyme ◽  
Maximum Activity ◽  
Free Enzyme ◽  
Expanded Perlite ◽  
Initial Activity ◽  
Optimum Ph ◽  
Scanning Electron

Abstract The α-amylase from Aspergillus oryzae was immobilized covalently onto expanded perlite (EP) and modified EP by treatment with TiO2 (EP-TiO2), dye HE3B (EP-HE3B) polyethylene terephthalate (PET)-hydrazide (EP-PET) and magnetite (EP-magnetite). The modified EP was characterized using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The supports were functionalized with aminopropyltriethoxysilane (APTES) and glutaraldehyde (GA). The optimum pH for free and immobilized α-amylase was 5.5. Temperature of maximum activity for free enzyme and immobilized enzyme on EP-HE3B was 50°C. The immobilized enzyme in EP-APTES this value was 55°C. The immobilized α-amylase in EP-APTES and EP-HE3B-APTES exhibited better thermostability than free enzyme. The immobilized derivatives showed moderate operational stability by retaining 50% of initial activity after seven successive reuses.

Comprehensive study of serratia peptidase immobilization from Serratia sp. ZF03 onto chitosan nanogels

2016 ◽  
Vol 41 (6) ◽  
Author(s):  
Navvabeh Salarizadeh ◽  
Sadegh Hasannia ◽  
Reza Hassan Sajedi ◽  
Navid Lamei ◽  
Afshin Mohsenifar ◽  
...  
Keyword(s):  
High Stability ◽  
Immobilized Enzyme ◽  
Immobilized Enzymes ◽  
Free Form ◽  
Original Activity ◽  
Ph Range ◽  
Powerful Demonstration ◽  
Thermal Stability Of ◽  
Scanning Electron ◽  
Comprehensive Study

AbstractObjective:In the present work, we have extended the study and immobilized the metalloprotease enzyme in glutaraldehyde cross-linked chitosan nanogels to scrutinize the enzyme’s features including stability over its soluble free form.Method:The immobilized metalloprotease was characterized using scanning electron microscopy (SEM), followed by Fourier transform infrared (FTIR) spectroscopy. The enzyme is optimally active at 50°C and pH range of 8.0–10.Results:Thermal stability of the enzyme enhanced when immobilized on the nanogel. After 5 min of incubation at 50°C, immobilized enzymes retained 60% of their original activity, while negligible activity (23%) was observed in the case of the free enzyme.Conclusion:The results obtained here provide a powerful demonstration of the benefits of taking the glutaraldehyde cross-linked chitosan matrices to enhance metalloprotease stability. The high stability of the immobilized enzyme serves to improve its performance for possible application on the industrial scale.

scholarly journals A novel all-in-one strategy for purification and immobilization of β-1,3-xylanase directly from cell lysate as active and recyclable nanobiocatalyst

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Lixi Cai ◽  
Yunmen Chu ◽  
Xin Liu ◽  
Yue Qiu ◽  
Zhongqi Ge ◽  
...  
Keyword(s):  
Immobilized Enzyme ◽  
Free Form ◽  
The Novel ◽  
Initial Activity ◽  
Algae Biomass ◽  
Cell Lysate ◽  
Ph Tolerance ◽  
Versatile Technique ◽  
Reaction Cycles ◽  
Direct Immobilization

Abstract Background Exploring a simple and versatile technique for direct immobilization of target enzymes from cell lysate without prior purification is urgently needed. Thus, a novel all-in-one strategy for purification and immobilization of β-1,3-xylanase was proposed, the target enzymes were covalently immobilized on silica nanoparticles via elastin-like polypeptides (ELPs)-based biomimetic silicification and SpyTag/SpyCatcher spontaneous reaction. Thus, the functional carriers that did not require the time-consuming surface modification step were quickly and efficiently prepared. These carriers could specifically immobilize the SpyTag-fused target enzymes from the cell lysate without pre-purification. Results The ELPs-SpyCatcher hardly leaked from the carriers (0.5%), and the immobilization yield of enzyme was up to 96%. Immobilized enzyme retained 85.6% of the initial activity and showed 88.6% of the activity recovery. Compared with free ones, the immobilized β-1,3-xylanase showed improved thermal stability, elevated storage stability and good pH tolerance. It also retained more than 70.6% of initial activity after 12 reaction cycles, demonstrating its excellent reusability. Conclusions The results clearly highlighted the effectiveness of the novel enzyme immobilization method proposed here due to the improvement of overall performance of immobilized enzyme in respect to free form for the hydrolysis of macromolecular substrates. Thus, it may have great potential in the conversion of algae biomass as well as other related fields.

scholarly journals A novel all-in-one strategy for purification and immobilization of β-1,3-xylanase directly from cell lysate as active and recyclable nanobiocatalyst

2019 ◽  
Author(s):  
Lixi Cai ◽  
Yunmeng Chu ◽  
Xin Liu ◽  
Yue Qiu ◽  
Zhongqi Ge ◽  
...  
Keyword(s):  
Immobilized Enzyme ◽  
Free Form ◽  
The Novel ◽  
Initial Activity ◽  
Algae Biomass ◽  
Cell Lysate ◽  
Ph Tolerance ◽  
Versatile Technique ◽  
Reaction Cycles ◽  
Direct Immobilization

Abstract Background: Exploring a simple and versatile technique for direct immobilization of target enzymes from cell lysate without prior purification is urgently needed. Thus, a novel all-in-one strategy for purification and immobilization of β-1, 3-xylanase was proposed, the target enzymes were covalently immobilized on silica nanoparticles via ELP-based biomimetic silicification and SpyTag/SpyCatcher spontaneous reaction. Thus, the functional carriers that did not require the time-consuming surface modification step were quickly and efficiently prepared. These carriers could specifically immobilize the SpyTag-fused target enzymes from the cell lysate without pre-purification. Results: The ELPs-SpyCatcher hardly leaked from the carriers (0.5%), and the immobilization yield of enzyme was up to 96%. Immobilized enzyme retained 85.6% of the initial activity and showed 88.6% of the activity recovery. Compared with free ones, the immobilized β-1, 3-xylanase showed improved thermal stability, elevated storage stability and good pH tolerance. It also retained more than 70.6% of initial activity after12 reaction cycles, demonstrating its excellent reusability. Conclusions: The results clearly highlighted the effectiveness of the novel enzyme immobilization method proposed here due to the improvement of overall performance of immobilized enzyme in respect to free form for the hydrolysis of macromolecular substrates. Thus, it may have great potential in the conversion of algae biomass as well as other related fields.

scholarly journals Immobilization of alpha-amylase produced by Bacillus circulans GRS 313

2003 ◽  
Vol 46 (2) ◽  
pp. 167-176 ◽  
Author(s):  
Gargi Dey ◽  
Singh Bhupinder ◽  
Rintu Banerjee
Keyword(s):  
Calcium Alginate ◽  
Immobilized Enzyme ◽  
Fold Increase ◽  
Alginate Beads ◽  
Hydrolysis Kinetics ◽  
Initial Activity ◽  
Reaction Conditions ◽  
Bead Size ◽  
Optimum Ph ◽  
Optimum Ph And Temperature

A maltooligosaccharide-forming amylase from B circulans GRS 313 was immobilized by entrapment in calcium alginate beads. The immobilized activity was affected by the size of the bead and bead size of 2mm was found to be most effective for hydrolysis. Kinetics constants, Km and Vmax were estimated and were found to be affected by the bead size. The catalytic activity of the enzyme was studied in presence of various starchy residues and metal ions. HgCl2, CuSO4 and FeCl3 caused inhibition of the enzyme. The reaction conditions, pH and temperature, was optimized using response surface methodology. At the optimum pH and temperature of 4.9 and 57ºC, the apparent activity was 25.6U/g of beads, resulting in almost 2-fold increase in activity. The immobilized enzyme showed a high operational stability by retaining almost 85% of the initial activity after seventh use.

scholarly journals Production of Aspartame by Immobilized Thermolysin

2019 ◽  
pp. 1232-1239
Author(s):  
Mohammed A Alsoufi ◽  
Raghad A. Aziz
Keyword(s):  
Reaction Time ◽  
Immobilized Enzyme ◽  
Bentonite Clay ◽  
Optimum Temperature ◽  
Initial Activity ◽  
Reaction Conditions ◽  
Original Activity ◽  
Ph Profile ◽  
Full Activity ◽  
Main Activity

The aim of this study was the production of aspartame by using immobilized thermolysin in bentonite clay. The yield of immobilized thermolysin in bentonite was 92% of the original enzyme amount. pH profile of free and immobilized enzyme was 7.0 and 7.5 respectively which was stable at 6.5-9.0 for 30min. The optimum temperature of both enzymes was 50°C, while they were stable at 65°C for 30min. however, they lost 52.73 and 61.72% from its main activity at 80°C respectively. Immobilized thermolysin has retained all activity within 27 days, but it kept 68.27% of initial activity when stored for 60 days at 4°C whereas, it retained a full activity after 20 continue usage. In addition, it retained 86.53% of its original activity after 30 continuing usages. The yield of produced aspartame was increased with reaction time; it was 9% after 1h and increased gradually to 100% after 10h at reaction conditions.

Lyapunov Control Strategy for Thermoelectric Cooler Activating an Ice-Clamping System

2018 ◽  
Vol 10 (4) ◽  
Author(s):  
Alexandra Mironova ◽  
Paolo Mercorelli ◽  
Andreas Zedler
Keyword(s):  
Manufacturing Systems ◽  
Control Strategies ◽  
Industrial Applications ◽  
Machining Process ◽  
Free Form ◽  
Cooling Power ◽  
Machining Processes ◽  
Clamping System ◽  
Ice Strength ◽  
Free Form Surfaces

Deformation-free clamping plays an important role in manufacturing systems helping to ensure zero-defect production. The fixture of workpieces during machining processes poses challenges not only for microparts but also for thin-walled pieces or free-form surfaces in macromanufacturing. To address this challenge, a nontraditional adhesive technique, using frozen water to clamp, is introduced in this paper. By increasing the cooling power and thus reducing the temperature of the clamping plate, higher adhesive ice strength and, therefore, a safer clamping system during machining process, can be achieved. The objective of this investigation is to ensure a stable low temperature and to compensate for thermal disturbances. Thanks to their structural robustness, Lyapunov-based control strategies demonstrate an appropriate capability to achieve these results in real industrial applications. Model design of the clamping system as well as simulation and experimental results are shown and discussed.

scholarly journals Immobilization of Eversa Lipase on Octyl Agarose Beads and Preliminary Characterization of Stability and Activity Features

Catalysts ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 511 ◽  
Author(s):  
Sara Arana-Peña ◽  
Yuliya Lokha ◽  
Roberto Fernández-Lafuente
Keyword(s):  
Immobilized Enzyme ◽  
Biodiesel Production ◽  
Free Form ◽  
Enzyme Specificity ◽  
Agarose Beads ◽  
The Stability ◽  
Isoform B ◽  
First Time ◽  
Commercial Lipase

Eversa is an enzyme recently launched by Novozymes to be used in a free form as biocatalyst in biodiesel production. This paper shows for first time the immobilization of Eversa (a commercial lipase) on octyl and aminated agarose beads and the comparison of the enzyme properties to those of the most used lipase, the isoform B from Candida antarctica (CALB) immobilized on octyl agarose beads. Immobilization on octyl and aminated supports of Eversa has not had a significant effect on enzyme activity versus p-nitrophenyl butyrate (pNPB) under standard conditions (pH 7), but immobilization on octyl agarose beads greatly enhanced the stability of the enzyme under all studied conditions, much more than immobilization on aminated support. Octyl-Eversa was much more stable than octyl-CALB at pH 9, but it was less stable at pH 5. In the presence of 90% acetonitrile or dioxane, octyl-Eversa maintained the activity (even increased the activity) after 45 days of incubation in a similar way to octyl-CALB, but in 90% of methanol, results are much worse, and octyl-CALB became much more stable than Eversa. Coating with PEI has not a clear effect on octyl-Eversa stability, although it affected enzyme specificity and activity response to the changes in the pH. Eversa immobilized octyl supports was more active than CALB versus triacetin or pNPB, but much less active versus methyl mandelate esters. On the other hand, Eversa specificity and response to changes in the medium were greatly modulated by the immobilization protocol or by the coating of the immobilized enzyme with PEI. Thus, Eversa may be a promising biocatalyst for many processes different to the biodiesel production and its properties may be greatly improved following a suitable immobilization protocol, and in some cases is more stable and active than CALB.

scholarly journals Covalent immobilization of an alkaline protease from Bacillus licheniformis

2018 ◽  
Vol 43 (6) ◽  
pp. 595-604
Author(s):  
Yakup Aslan ◽  
Derya Ömerosmanoğlu ◽  
Eda Öndül Koç
Keyword(s):  
Bacillus Licheniformis ◽  
Immobilized Enzyme ◽  
Milk Proteins ◽  
Covalent Immobilization ◽  
Initial Activity ◽  
Optimum Conditions ◽  
Continuous Processes ◽  
Operational Conditions ◽  
Optimum Ph ◽  
Soluble Enzymes

Abstract Objective Since the soluble enzymes can not be used in repeated reactions and are not stable in operational conditions and not suitable for continuous processes, this study aimed the covalent immobilization of Bacillus licheniformis protease (BLP) onto Eupergit CM. Methods Optimum conditions for immobilization were determined by changing the conditions individually. The proteins and L-tyrosine were determined by UV/VIS spectrophotometer. Results The immobilization resulted in 100% immobilization and 107.7% activity yields. The optimum pH (7–8) and the optimum temperature (70°C) have not changed after immobilization. The Km values for free and immobilized enzyme were 26.53 and 37.59 g/L, while the Vmax values were 2.84 and 3.31 g L-Tyrosine/L·min, respectively. The immobilized enzyme has not lost its initial activity during the repeated 20 uses and 20 days of storage. The milk proteins were hydrolyzed in 2 h by using immobilized enzyme. The pH of the milk dropped from 6.89 to 6.53, the color was clearer but there was no change in the smell or the taste. Conclusion Consequently, it can be said that the immobilized BLP obtained can be used for industrial purposes.

scholarly journals Study of selection and purification of Brazilian bentonite clay by elutriation: a XRF, SEM and Rietveld analysis

Cerâmica ◽  
2016 ◽  
Vol 62 (361) ◽  
pp. 1-8 ◽  
Author(s):  
J. L. Alves ◽  
A. E. Zanini ◽  
M. E. de Souza ◽  
M. L. F. Nascimento
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Rietveld Method ◽  
Bentonite Clay ◽  
Rietveld Analysis ◽  
Industrial Applications ◽  
X Ray Diffraction ◽  
X Ray ◽  
Almost All ◽  
Scanning Electron

Abstract Clays obtained from nature have a lot of impurities. Therefore, for best using of these materials, it is necessary its selection and purification. Thus, the aim of this work is to separate and to purify the smectite fractions using water as a solvent at a low flux mixed with a bentonite clay extracted from a mine in Vitória da Conquista - Bahia / Brazil. For this a separation method of fractions of expandable clays based on the Stokes' Law was applied - this process is called elutriation, in order to ensure and to expand possible industrial applications of this material. The samples were characterized by analysis of X-ray diffraction, X-ray fluorescence and scanning electron microscopy. The Rietveld method enabled the quantification of main phase minerals: montmorillonite, kaolinite, nontronite and quartz, reaching 85% in mass of montmorillonite phase at the end of the process. Results showed that the method used was efficient to remove almost all quartz, carbonates and organic matter from the sample. It was also observed a monomodal grain size distribution of elutriated materials with thinner grains, around (18.1 ± 1.8) μm at the end of the process. It has been concluded that the method developed and applied showed promising characters to be applied to elutriate kilograms of clays and could be used in industrial scale.

Sign in / Sign up

Export Citation Format

Share Document