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Up-Streaming Process for Glucose Oxidase by Thermophilic Penicillium sp. in Shake Flask  [cached]
Muhammad Mohsin JAVED,Aroosh SHABIR,Sana ZAHOOR,Ikram UL-HAQ
Walailak Journal of Science and Technology , 2012, DOI: 10.2004/vol10iss1pp
Abstract: The present study is concerned with the production of glucose oxidase (GOD) from thermophilic Penicillium sp. in 250 mL shake flask. Fourteen different strains of thermophilic Penicillium sp. were isolated from the soil and were screened for glucose oxidase production. IIBP-13 strain gave maximum extra-cellular glucose oxidase production as compared to other isolates. Effect of submerged fermentation in shaking and static conditions, different carbon sources and incubation period on the production of extra-cellular glucose oxidase was studied. Maximum yield (0.325 U/mL) of extra-cellular glucose oxidase was obtained after 72 hrs of incubation at 45 oC using submerged fermentation technique in shaking conditions utilizing sucrose as carbon source.
Production of rabbit antibodies against purified Glucose oxidase
Zia, Muhammad Anjum;Ain, Qurat-ul;Iftikhar, Tehreema;Abbas, Rao Zahid;Rahman, Khalil-ur;
Brazilian Archives of Biology and Technology , 2012, DOI: 10.1590/S1516-89132012000100008
Abstract: glucose oxidase is an active oxygen species generating enzyme produced from aspergillus niger grown in submerged fermentation. disintegration of the mycelium resulted in high glucose oxidase activity that was subjected to ammonium sulfate precipitation at 60-85% saturation rates that resulted to 6.14 u mg -1 specific activity. purification of enzyme by anion exchange column (deae-cellulose) resulted into 22.53 u mg-1 specific activity and 10.27 fold purification. this was applied to sephadex g-200 column for gel filtration chromatography. it was observed that enzyme achieved 59.37 u mg-1of specific activity with 27.08 fold purity and 64.36% recovery. purified glucose oxidase was injected into rabbits through intravenous route, to raise the glucose oxidase antibodies. after 30 days incubation period, the rabbits were slaughtered and serum was separated from blood. the antibodies were isolated by ammonium sulfate precipitation and confirmed by agar gel precipitation test. this could be a convenient and low cost alternate assay for the estimation of glucose oxidase in biological fluids. moreover, such antibodies against the said enzyme could be used in various therapeutic and diagnostic applications.
Stabilization of glucose oxidase with cyclodextrin-branched carboxymethylcellulose
Matos,Madyu; Simpson,Benjamin K; Ramírez,Héctor L; Cao,Roberto; Torres-Labandeira,Juan J; Hernández,Karel;
Biotecnolog?-a Aplicada , 2012,
Abstract: we present a methodology for improving some enzymatic characteristics of glucose oxidase (gox) (ec the enzyme was chemically modified with a ?-cyclodextrin-branched carboxymethylcellulose polymer (cmc-cd), using carbodiimide as coupling agent. the obtained neoglycoenzyme had 0.78 mol of polysaccharide per mol of gox and retained 67% of its initial activity. comparison of some characteristics of the modified and free enzymes showed a higher km for derivatized gox and better thermostability, which increased from 45 °c to 51 °c. in addition, derivatization of gox with cmc-cd increased its resistance to inactivation at 45 °c by 2.2-fold, protected the molecule against inactivation with the anionic surfactant sodium dodecylsulphate to the point that it retained 75% of its activity after an incubation of 3 h, and extended its ph tolerance toward alkaline ph (7.5). covalent glycosidation of glucose oxidase with cd-branched carboxymethylcellulose polymer constitutes therefore an effective strategy for enhancing the stability of this enzyme.
Enhanced production of glucose oxidase from UVmutant of Aspergillus niger
M Ramzan, T Mehmood
African Journal of Biotechnology , 2009,
Abstract: UV rays were used as mutagen in wild type strain of Aspergillus niger for enhanced production of glucose oxidase. After mutangenization and selection, mutant A. niger strains, resistant to 2-deoxy-Dglucose were obtained. The mutants showed 1.57 and 1.98 fold increase in activities of extra and intra cellular glucose oxidase respectively in comparison with the parental strain. Out of 6 mutants, mutant U-6 was selected as the best producer of glucose oxidase after 36 h of fermentation using black strap molasses as substrate.
Effect of Stirrer Speed and Aeration Rate on the Production of Glucose Oxidase by Aspergillus niger  [PDF]
Jafari A.R.,M.H. Sarrafzadeh,I. Alemzadeh,M. Vosoughi
Journal of Biological Sciences , 2007,
Abstract: Dissolved oxygen tension and shear stress as two very important factors in fungal fermentation were studied in the batch cultures of Aspergillus niger. The intention was to maximize the total activity of glucose oxidase produced in a 5-1 bench-top bioreactor. 300 rpm found to be optimum for enzyme production, however in higher mixing rates higher growth was achieved. The maximum activity of glucose oxidase was obtained in 1.5 vvm while the best aeration rate for growth was 2 vvm. Glucose oxidase with the activity of 548 U mL-1 was produced in 1.5 vvm and 300 rpm as the optimum conditions.
Polystyrene Attached Pt(IV)–Azomethine, Synthesis and Immobilization of Glucose Oxidase Enzyme  [PDF]
Nur?en Sari,Esin Antepli,Dilek Nartop,Nurdan Kurnaz Yetim
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms130911870
Abstract: Modified polystyrene with Pt(IV)–azomethine (APS–Sch–Pt) was synthesized by means of condensation and demonstrated to be a promising enzyme support by studying the enzymatic properties of glucose oxidase enzyme (GOx) immobilized on it. The characteristics of the immobilized glucose oxidase (APS–Sch–Pt–GOx) enzyme showed two optimum pH values that were pH = 4.0 and pH = 7. The insertion of stable Pt(IV)–azomethine spacers between the polystyrene backbone and the immobilized GOx, (APS–Sch–Pt–GOx), increases the enzymes’ activity and improves their affinity towards the substrate even at pH = 4. The influence of temperature, reusability and storage capacity on the free and immobilized glucose oxidase enzyme was investigated. The storage stability of the immobilized glucose oxidase was shown to be eleven months in dry conditions at +4 °C.
Immobilization of Glucose Oxidase in Alginate-Chitosan Microcapsules  [PDF]
Xia Wang,Ke-Xue Zhu,Hui-Ming Zhou
International Journal of Molecular Sciences , 2011, DOI: 10.3390/ijms12053042
Abstract: In order to improve its stability and catalytic rate in flour, the immobilization of glucose oxidase (GOX) was investigated in this work. The enzyme was encapsulated in calcium alginate-chitosan microspheres (CACM) using an emulsification-internal gelation-GOX adsorption?chitosan coating method. The interaction between alginate and chitosan was confirmed by infrared spectroscopy (IR). The resultant CACM in wet state, whose morphology was investigated by scanning electron microscopy (SEM), was spherical with a mean diameter of about 26 μm. The GOX load, encapsulation efficiency and activity of the CACM-GOX were influenced by concentration of chitosan, encapsulation time and encapsulation pH. The highest total enzymatic activity and encapsulation efficiency was achieved when the pH of the adsorption medium was near the isoelectric point (p I) of GOX, approximately pH 4.0. In addition, the molecular weight of chitosan also evidently influenced the encapsulation efficiency. Storage stabilities of GOX samples were investigated continuously over two months and the retained activity of CACM-GOX was 70.4%, markedly higher than the 7.5% of free enzyme. The results reveal the great potential of CACM-GOX as a flour improver.
Glucose oxidase immobilization onto carbon nanotube networking  [PDF]
V. A. Karachevtsev,A. Yu. Glamazda,E. S. Zarudnev,M. V. Karachevtsev,V. S. Leontiev,A. S. Linnik,O. S. Lytvyn,A. M. Plokhotnichenko,S. G. Stepanian
Physics , 2012,
Abstract: When elaborating the biosensor based on single-walled carbon nanotubes (SWNTs), it is necessary to solve such an important problem as the immobilization of a target biomolecule on the nanotube surface. In this work, the enzyme (glucose oxidase (GOX)) was immobilized on the surface of a nanotube network, which was created by the deposition of nanotubes from their solution in 1,2-dichlorobenzene by the spray method. 1-Pyrenebutanoic acid succinimide ester (PSE) was used to form the molecular interface, the bifunctional molecule of which provides the covalent binding with the enzyme shell, and its other part (pyrene) is adsorbed onto the nanotube surface. First, the usage of such a molecular interface leaves out the direct adsorption of the enzyme (in this case, its activity decreases) onto the nanotube surface, and, second, it ensures the enzyme localization near the nanotube. The comparison of the resonance Raman (RR) spectrum of pristine nanotubes with their spectrum in the PSE environment evidences the creation of a nanohybrid formed by an SWNT with a PSE molecule which provides the further enzyme immobilization. As the RR spectrum of an SWNT:PSE:GOX film does not essentially differ from that of SWNT:PSE ones, this indicates that the molecular interface (PSE) isolates the enzyme from nanotubes strongly enough. The efficient immobilization of GOX along the carbon nanotubes due to PSE is confirmed with atom-force microscopy images. The method of molecular dynamics allowed us to establish the structures of SWNT:PSE:GOX created in the aqueous environment and to determine the interaction energy between hybrid components. In addition, the conductivity of the SWNT network with adsorbed PSE and GOX molecules is studied.
Following Glucose Oxidase Activity by Chemiluminescence and Chemiluminescence Resonance Energy Transfer (CRET) Processes Involving Enzyme-DNAzyme Conjugates  [PDF]
Angelica Niazov,Ronit Freeman,Julia Girsh,Itamar Willner
Sensors , 2011, DOI: 10.3390/s111110388
Abstract: A hybrid consisting of glucose oxidase-functionalized with hemin/G-quadruplex units is used for the chemiluminescence detection of glucose. The glucose oxidase-mediated oxidation of glucose yields gluconic acid and H2O2. The latter in the presence of luminol acts as substrate for the hemin/G-quadruplex-catalyzed generation of chemiluminescence. The glucose oxidase/hemin G-quadruplex hybrid was immobilized on CdSe/ZnS quantum dots (QDs). The light generated by the hybrid, in the presence of glucose, activated a chemiluminescence resonance energy transfer process to the QDs, resulting in the luminescence of the QDs. The intensities of the luminescence of the QDs at different concentrations of glucose provided an optical means to detect glucose.
Journal of the Chilean Chemical Society , 2011, DOI: 10.4067/S0717-97072011000100022
Abstract: in this work, we report the effect of the direct successive modifications with glucose oxidase onto boron doped diamond electrode (bdd). the modification due to the enzyme adsorption, on the potentiodynamic response of the electrode, was evaluated using fe(cn)64-/3- red-ox couple on the electrolyte and the aep variations were related with the number of modifications. contact angle measurements and the electrochemical impedance spectra were also used to characterized the modifications and they showed variations in the same way that the potentiodynamic data.
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