scholarly journals Immobilization and Characterization of Bacillus Thuringiensis HCB6 Amylase in Calcium Alginate Matrix

Molekul ◽  
2017 ◽  
Vol 12 (1) ◽  
pp. 70 ◽  
Author(s):  
Zusfahair Zusfahair ◽  
Dian Riana Ningsih Dian Riana Ningsih ◽  
Dwi Kartika Dwi Kartika ◽  
Amin Fatoni Amin Fatoni ◽  
Indah Permatawati Indah Permatawati
Keyword(s):  
Incubation Time ◽  
Substrate Concentration ◽  
Contact Time ◽  
Alginate Bead ◽  
Residual Activity ◽  
Immobilized Enzymes ◽  
Optimum Ph ◽  
Km Value ◽  
Ca Alginate

Free enzyme in solution react with substrates to result in products which cannot be recovered for reuse. These problems can be overcome to a certain extent by the use of enzyme immobilization method. Immobilized enzymes are more robust and more resistant to condition changes. More importantly, the heterogeneous immobilized enzyme systems allow an easy recovery of both enzymes and products, multiple re-uses of enzymes, and continuous operation of enzymatic processes. Entrapment of enzymes in Ca-alginate is one of the simplest methods of immobilization. The aim of this research was to obtain the optimum condition of the making of immobilized amylase beads using a Ca-alginate bead and to determine its characteristics. The optimization of immobilized amylase beads includes variation of sodium alginates and variations of enzyme contact time with CaCl2. The characterization of immobilized amylase includes determination of optimum substrate concentration, optimum pH, and optimum incubation time as well as amylase stability test. Amylase activity was determined by using dinitro salicylic (DNS) method. The results showed that the optimum immobilized amylase obtained at alginate concentrations of 5% (w/v), contact time of 60 minutes and immobilization efficiency of 67.5%. Furthermore, immobilized amylase showed optimum substrate concentration of 1.5-2.5% (w/v), optimum pH of 6, an optimum incubation time of 20 minutes with the activity of 179.8 U/mL. The KM value for free amylase and immobilized amylases were 0.3 mM and 0.12 mM respectively. Vmax value for free amylase and immobilized amylases were 105.3 U/mL and 10.1 U/mL respectively. Immobilized Amylase can be used up to six times with the residual activity of 52.7%.

Immobilization and Characterization of Tannase and its Haze-removing

2009 ◽  
Vol 15 (6) ◽  
pp. 545-552 ◽  
Author(s):  
Erzheng Su ◽  
Tao Xia ◽  
Liping Gao ◽  
Qianying Dai ◽  
Zhengzhu Zhang
Keyword(s):  
Kinetic Parameter ◽  
High Activity ◽  
Green Tea ◽  
Storage Stability ◽  
Residual Activity ◽  
Black Tea ◽  
Optimum Temperature ◽  
Oolong Tea ◽  
Optimum Ph

Tannase was effectively immobilized on alginate by the method of crosslinking-entrapment-crosslinking with a high activity recovery of 76.6%. The properties of immobilized tannase were investigated. Its optimum temperature was determined to be 35 ° C, decreasing 10 °C compared with that of free enzyme, whereas the optimum pH of 5.0 did not change. The thermal and pH stabilities of immobilized tannase increased to some degree. The kinetic parameter, Km, for immobilized tannase was estimated to be 11.6 × 10-4 mol/L. Fe2+ and Mn2+ could activate the activity of immobilized tannase. The immobilized tannase was also applied to treat the tea beverage to investigate its haze-removing effect. The content of non-estern catechins in green tea, black tea and oolong tea increased by 52.17%, 12.94% and 8.83%, respectively. The content of estern catechins in green tea, oolong tea and black tea decreased by 20.0%, 16.68% and 5.04%, respectively. The anti-sediment effect of green tea infusion treated with immobilized tannase was significantly increased. The storage stability and reusability of the immobilized tannase were improved greatly, with 72.5% activity retention after stored for 42 days and 86.9% residual activity after repeatedly used for 30 times.

scholarly journals Synthesis and Characterization of Piperidin-4-one Derivatives Using Green Solvent

2020 ◽  
Vol 32 (4) ◽  
pp. 727-732
Author(s):  
Harish Sharma ◽  
Rajesh Kumar ◽  
Mahesh Chandra Vishwakarma ◽  
Sushil Kumar Joshi ◽  
Narender Singh Bhandari
Keyword(s):  
Metal Ions ◽  
Contact Time ◽  
Metal Ion ◽  
Low Cost ◽  
Ion Concentration ◽  
Green Solvent ◽  
Optimum Ph ◽  
Influence Of Ph ◽  
Biosorption Equilibrium

In present study, Pyras pashia leaves were used as low cost biosorbent to study biosorption of Cu(II), Pb(II) and Cd(II) ions from contaminated wastewater. In the employed batch methods pH, contact time, metal ion concentration, temperature, biosorbent doses were taken as study parameters. The pH was varied from pH 1-9 to study the influence of pH on biosorption of metal ions by Pyras pashia. The optimum pH for the removal of Cu(II), Pb(II) and Cd(II) is observed at pH 5. The biosorption equilibrium time was varied between 15-75 min. Langmuir, Freundlich and Temkin isotherms were employed to study the biosorption. The biosorption parameter fits well with Langmuir isotherm. The biosorption of metal ions was increased with increasing biosorbent dose and contact time while increase in pH, metal ion concentration and temperature decrease the biosorption. Thermodynamic data suggest that the bisorption process was spontaneous, feasible and endothermic.

Characterization of amoA and hao Genes Responsible for Ammonia Oxidation Reaction in CANON System

2011 ◽  
Vol 183-185 ◽  
pp. 1014-1019
Author(s):  
Hai Yan Zou ◽  
Jun Li Huang ◽  
Fang Fang ◽  
Jin Song Guo
Keyword(s):  
Nitrogen Removal ◽  
Oxidation Reaction ◽  
High Efficiency ◽  
Ammonia Oxidation ◽  
Residual Activity ◽  
Maximum Activity ◽  
Ammonia Oxidizing Bacteria ◽  
Hydroxylamine Oxidoreductase ◽  
Optimum Ph

In this research the genes (amoA and hao) for ammonia monooxygenase (AMO) and hydroxylamine oxidoreductase (HAO) responsible for ammonia oxidation reaction in completely autotrophic nitrogen removal over nitrite process were cloned and sequenced, and the recombinant protein of AMO and HAO was expressed and characterized. The optimum temperature for AMO activity was 55 °C and more than 40% of the maximum activity was retained from 15-50 °C. The optimum pH for the enzyme was found to be pH 11.0. The highest activity for HAO was observed at 45 °C. More than 50% of the maximum activity was retained even at 55 °C. The dependence of HAO on pH was strong and only average 15% of residual activity left at pH ranging from 3.0-9.0. Study on the molecular and biochemistry properties of recombinant AMO and HAO will benefit for the manipulation of ammonia-oxidizing bacteria to achieve the goal of high efficiency of nitrogen removal.

scholarly journals Purification and characterization of versatile peroxidase from Lentinus squarrosulus and its application in biodegradation of lignocellulosics

2019 ◽  
Vol 6 (6) ◽  
pp. 280-286
Author(s):  
Aarthi Ravichandran ◽  
Ramya G Rao ◽  
Maheswarappa Gopinath ◽  
Manpal Sridhar
Keyword(s):  
Finger Millet ◽  
Nutritive Value ◽  
Crop Residues ◽  
Specific Activity ◽  
Gel Filtration ◽  
Versatile Peroxidase ◽  
Purification And Characterization ◽  
Optimum Ph ◽  
Km Value

Versatile Peroxidases are high redox potential peroxidases capable of degrading lignin of lignocellulosic crop residues. Hence Versatile Peroxidases are prominent biocatalysts in upgrading lignocellulosic biomass for biotechnological applications. In the interest of exploiting the potential of Versatile Peroxidase in improving the digestibility of crop residues through delignification, a novel Versatile Peroxidase was purified and characterized from the immobilized cultures of native isolate Lentinus squarrosulus. The enzyme was purified with a specific activity of 62 U/mg through ion exchange and gel filtration chromatographic procedures. The enzyme possessed high affinity towards RB5 and manganese with a Km value of 6.84 µM for RB5 and 0.15 mM for manganese. The optimum temperature for oxidation was identified to be 30°C and optimum pH for manganese and RB5 oxidation was 5 and 3 respectively. Reactivity of the enzyme towards diverse substrates was investigated besides studying the effect of metal ions and inhibitors on RB5 oxidation. The enhanced potential of this purified Versatile Peroxidase in biodegradation of crop residues was demonstrated through augmentation of digestibility of finger millet and paddy straws by 20%.The results demonstrated that Versatile Peroxidase from Lentinus squarrosulus is capable of enhancing the nutritive value of crop residues through delignification

scholarly journals PENGARUH EKSTRAK METANOL DAUN PEPAYA (Carica papaya L.) TERHADAP AKTIVITAS ENZIM LIPASE

KOVALEN ◽  
2017 ◽  
Vol 3 (3) ◽  
pp. 211
Author(s):  
Nurhaeni Nurhaeni ◽  
Ahmad Ridhay ◽  
Magfira Magfira
Keyword(s):  
Enzyme Activity ◽  
Lipase Activity ◽  
Incubation Time ◽  
Substrate Concentration ◽  
Goal Attainment ◽  
Carica Papaya ◽  
Methanol Extract ◽  
Ph Optimum ◽  
Lipase Enzyme ◽  
Optimum Ph

Has conducted research on the effects of methanol extract of leaves papaya (Carica papaya L.) Against Lipase Enzyme Activity. This study aimed to obtain information in a methanol extract inhibits lipase activity. The method used is Complete Random Design (RAL), with goal attainment is done by determining the incubation time lipase enzyme, pH optimum lipase enzyme, and maximum substrate concentration lipase enzyme. And determining the effect of the methanol extract to inhibit the lipase enzyme activity. The results showed that the best incubation time of lipase obtained by time of 120 minutes, the optimum pH 7 and the maximum substrate concentration of 4%. With the highest activity were obtained 16.94 mol /ml.menit, 13.33 mol / ml.menit, and 12.89 mol / ml.menit. The methanol extract of papaya leaves can inhibit the lipase enzyme activity the best concentration of 2% with the acquisition activity of 3.67 mol/ml.menit.Keyword: papaya, lipase, incubation time, optimum pH, substrate concentration.

scholarly journals Immobilization of Purified Pectin Lyase from Acinetobacter calcoaceticus onto Magnetic Carboxymethyl Cellulose Nanoparticles and Its Usability in Food Industry

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Esen Tasgin ◽  
Aynur Babagil ◽  
Hayrunnisa Nadaroglu ◽  
Patricia E. Allegretti
Keyword(s):  
Fe3o4 Nanoparticles ◽  
Carboxymethyl Cellulose ◽  
Food Industry ◽  
Acinetobacter Calcoaceticus ◽  
Immobilized Enzymes ◽  
Pectin Lyase ◽  
Three Phase ◽  
Optimum Ph ◽  
Ft Ir

An important component of the pectinase enzyme complex is pectin lyase (polymethylgalacturonate lyase; EC 4.2.2.10). In this study, extracellular pectin lyase enzyme was produced from Acinetobacter calcoaceticus bacteria. Pectin lyase was then purified using three-phase precipitation (TPP) technique with 25.5% yield. The pectin lyase was immobilized covalently via the L-glutaraldehyde spacer to the carboxymethyl cellulose. The immobilized pectin lyase was magnetized using Fe3O4 nanoparticles. Purified pectin lyase was connected to magnetized support material after 90 min at the rate of 80%. The most appropriate immobilization conditions were determined as pH 8 and 30°C. By characterizing the free and immobilized enzyme, KM, Vmax, and optimum pH and optimum temperature values were determined. It was optimum pH 8 and temperature 50°C for both free and immobilized pectin lyase. The structural characterization of the immobilized pectin lyase modified with Fe3O4 nanoparticles was carried out by SEM, FT-IR, and XRD chromatographic analyses. At the end of the study, free and immobilized enzymes were used for purification of some fruit juices and results were compared.

scholarly journals RELATIVE CHARACTERIZATION OF IMMOBILIZED BETA-GLUCOSIDASE ON CALCIUM-ALGINATE AND ACID FUNCTIONALIZED MULTIWALLED CARBON NANOTUBES

2019 ◽  
Vol 81 (3) ◽  
Author(s):  
Ahmad T. Jameel ◽  
Kauthar Y. Maalim ◽  
Faridah Yusof
Keyword(s):  
Carbon Nanotubes ◽  
Multiwalled Carbon Nanotubes ◽  
Incubation Time ◽  
Carbon Nanomaterials ◽  
Immobilized Enzyme ◽  
Alginate Beads ◽  
Multiwalled Carbon ◽  
Mwcnt Surface ◽  
Ca Alginate

Natural polymeric gel such as alginate and carrageenan, and carbon nanomaterials, especially MWCNT and graphene are gaining increasing popularity as immobilization support owing to their biocompatibility. Thus, this study attempts to make a relative characterization of the immobilized β-glucosidase on alginate and multiwalled carbon nanotubes (MWCNT) to assess their relative merits as biocatalyst. Acid functionalization of MWCNT lead to the formation of carboxyl groups at the MWCNT surface which seemed to have role in the stable attachment of the enzyme on the MWCNT surface. The effectiveness of the immobilized enzyme was evaluated using hydrolysis of p-nitrophenyl-β-D-glucopyranoside to p-nitrophenol. The optimum immobilization conditions were found to be 17 mg MWCNT and 4 h incubation time for MWCNT, and 3.5 wt% sodium alginate solution and 2 h incubation time for the Ca-alginate beads. The immobilization yield on MWCNT was found to be 96% and that for the Ca-alginate beads was 86%. The residual activity of the enzyme at the third cycle of subsequent reuse was 85% for the enzyme-MWCNT and almost 50% for the enzyme-alginate beads. Both, Ca-alginate and MWCNT immobilized enzyme were found to follow Michaelis-Menten kinetics. The kinetic data were best represented by the Langmuir plot. The kinetic constants Vmax and Km for the MWCNT immobilized enzyme were obtained as 1.324 mM/min and 0.801 mM, respectively, while for the alginate immobilized enzyme, the constants predicted were 1.240 mM/min and 0.524 mM, respectively. Thus MWCNT immobilized β-glucosidase exhibited greater stability in terms of activity and reusability compared to Ca-alginate beads.

scholarly journals Synthesis & Characterization of Magnetit (Fe3O4) and Its Applications As Adsorbent Methylene Blue

2017 ◽  
Vol 11 (2) ◽  
pp. 61
Author(s):  
Retno Agnestisia
Keyword(s):  
Methylene Blue ◽  
Contact Time ◽  
Coprecipitation Method ◽  
X Ray Diffraction ◽  
Ph Optimum ◽  
Adsorption Study ◽  
Batch System ◽  
Optimum Ph ◽  
Blue Solution

Synthesis, characterization and adsorption study of magnetite have beenconducted. Magnetite was synthesized by coprecipitation method. The characterizations of magnetite were carried out with spectroscopy FTIR (Fourier Transform Infrared) and XRD (X-ray diffraction). The adsorption study was conducted using a batch system with the studied adsorption study including optimum pH, optimum contact time and adsorption equilibrium. The results showed that coprecipitation method has succeeded to form magnetite that has magnetism properties. Magnetite can adsorbed methylene blue from aqueous phase, with the maximum adsorption at pH 5 and contact time of 90 minutes.Adsorption of methylene blue by magnetite follows the adsorption pattern of the Langmuir isotherm with the adsorption energy of 25.59 kJ/mol and adsorption capacity of 43.86 mg/g. The results of magnetite synthesis can accelerate the process of separating the adsorbent particles in a methylene blue solution using an external magnetic field.Keywords : magnetite, coprecipitation, adsorption, and methylene blue.

scholarly journals Characterization of Cross-Linked Enzyme Aggregates of the Y509E Mutant of a Glycoside Hydrolase Family 52 β-xylosidase from G. stearothermophilus

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 451
Author(s):  
Gabriela Romero ◽  
Lellys M. Contreras ◽  
Carolina Aguirre ◽  
Jeff Wilkesman ◽  
Josefa María Clemente-Jiménez ◽  
...  
Keyword(s):  
Ammonium Sulfate ◽  
Glycoside Hydrolase ◽  
Biochemical Characterization ◽  
Xylanase Activity ◽  
Immobilized Enzymes ◽  
Cross Linking ◽  
Glycoside Hydrolase Family ◽  
Km Value ◽  
Hydrolase Family

Cross-linked enzyme aggregates (CLEAs) of the Y509E mutant of glycoside hydrolase family 52 β-xylosidase from Geobacillus stearothermophilus with dual activity of β-xylosidase and xylanase (XynB2Y509E) were prepared. Ammonium sulfate was used as the precipitant agent, and glutaraldehyde as cross-linking agent. The optimum conditions were found to be 90% ammonium sulfate, 12.5 mM glutaraldehyde, 3 h of cross-linking reaction at 25 °C, and pH 8.5. Under these (most effective) conditions, XynB2Y509E-CLEAs retained 92.3% of their original β-xylosidase activity. Biochemical characterization of both crude and immobilized enzymes demonstrated that the maximum pH and temperature after immobilization remained unchanged (pH 6.5 and 65 °C). Moreover, an improvement in pH stability and thermostability was also found after immobilization. Analysis of kinetic parameters shows that the Km value of XynB2Y509E-CLEAs obtained was slightly higher than that of free XynB2Y509E (1.2 versus 0.9 mM). Interestingly, the xylanase activity developed by the mutation was also conserved after the immobilization process.

scholarly journals Immobilization of Naringinase from Penicillium decumbens on Chitosan Microspheres for Debittering Grapefruit Juice

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4234 ◽  
Author(s):  
Joanna Bodakowska-Boczniewicz ◽  
Zbigniew Garncarek
Keyword(s):  
Grapefruit Juice ◽  
Immobilized Enzyme ◽  
Maximum Activity ◽  
Chitosan Microspheres ◽  
Optimum Ph ◽  
Potential Applicability ◽  
Km Value ◽  
Hydrolysis Of ◽  
Thermal Stability Of

Naringinase is an enzyme complex which exhibits α-l-rhamnosidase and β-d-glucosidase activity. This enzymatic complex catalyzes the hydrolysis of naringin (4′,5,7-trihydroxy flavanone 7-rhamnoglucoside), the main bittering component in grapefruit. Reduction of the level of this substance during the processing of juice has been the focus of many studies. The aim of the study was the immobilization of naringinase on chitosan microspheres activated with glutaraldehyde and, finally, the use of such immobilized enzyme for debittering grapefruit juice. The effect of naringinase concentration and characterization of the immobilized enzyme compared to the soluble enzyme were investigated. The maximum activity was observed at optimum pH 4.0 for both free and immobilized naringinase. However, the optimum temperature was shifted from 70 to 40 °C upon immobilization. The KM value of the immobilized naringinase was higher than that of soluble naringinase. The immobilization did not change the thermal stability of the enzyme. The immobilized naringinase had good operational stability. This preparation retained 88.1 ± 2.8% of its initial activity after ten runs of naringin hydrolysis from fresh grapefruit juice. The results indicate that naringinase immobilized on chitosan has potential applicability for debittering and improving the sensory properties of grapefruit juices.

Sign in / Sign up

Export Citation Format

Share Document