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A new size and shape controlling method for producing calcium alginate beads with immobilized proteins  [PDF]
Yan Zhou, Shin’ichiro Kajiyama, Hiroshi Masuhara, Yoichiro Hosokawa, Takahiro Kaji, Kiichi Fukui
Journal of Biomedical Science and Engineering (JBiSE) , 2009, DOI: 10.4236/jbise.2009.25043
Abstract: A method for producing size- and shape-con-trolled calcium alginate beads with immobilized proteins was developed. Unlike previous cal-cium alginate bead production methods, pro-tein-immobilized alginate beads with uniform shape and sizes less then 20 micrometers in diameter could successfully be produced by using sonic vibration. BSA and FITC-conjugated anti-BSA antibodies were used to confirm pro-tein immobilization in the alginate beads. Pro-tein diffusion from the beads could be reduced to less than 10% by cross-linking the proteins to the alginate with 1-ethyl-3-(3-dimethylamino-propyl)carbodiimide (EDC) and N-hydroxysul-fosuccinimide (NHSS). The calcium alginate beads could also be arranged freely on a slide glass by using a femtosecond laser.
Continuous removal and recovery of lead by alginate beads, free and alginate-immobilized Chlorella vulgaris
MSA Hameed
African Journal of Biotechnology , 2006,
Abstract: This study examines the possibility of using Chlorella vulgaris cells in repeated lead adsorption/desorption cycles. Alginate beads and immobilized with algal cells were more effective and suitable than free cells. Consistently high lead removal (>90%) and recovery (about 100%) were achieved. Lead adsorption was mainly via the alginate matrix and minor contribution was made by algae. Free cells were difficult to handle and give inconsistent lead removal and recovery throughout the experiment.
Rifamycins Production by Amycolatopsis mediterranei in Batch and Repeated Batch Cultures Using Immobilized Cells in Alginate and Modified Alginate Beads  [PDF]
Hesham A. El-Enshasy,Usama I. Beshay,Ahmed I. El-Diwany,Hoda M. Omar
Journal of Applied Sciences , 2007,
Abstract: The production of rifamycins B and SV by Amycolatopsis mediterranei using immobilization technique was investigated. Alginate beads proved to be an alternative method for the production of rifamycin antibiotic as it has many advantage over using free cells such as it enables the operation at higher dilution rates without the danger of wash out, ease of handling and facilitates recycling or reverse of using microorganism. Different hardening agents were used to improve the stability of the beads and decrease cells escapement. Gum Arabic and gellan gum were used and the rate of rifamycin production increased by using gellan gum as hardening agent compared to pure alginate beads. The rifamycins B and SV increased from 685 to 810 and from 547.5 to 702 mg L-1, respectively by using gellan-gum modified beads compared to the non-treated beads. In repeated batch production, the beads were stable and no breaking of the gel beads was observed throughout the experiment time. The total amount of rifamycin B and SV during the five repeated batches (each of 144 h) reached 3360 and 2309 mg L-1, respectively. On reducing the batch time to only 72 h, the antibiotic production was not influenced and the total concentration of rifamycins B and SV for five batches was 3785 and 2393 mg L-1, respectively.
Rapid Degradation of Phenanthrene by Using Sphingomonas sp. GY2B Immobilized in Calcium Alginate Gel Beads  [PDF]
Xue-Qin Tao,Gui-Ning Lu,Jie-Ping Liu,Ting Li,Li-Ni Yang
International Journal of Environmental Research and Public Health , 2009, DOI: 10.3390/ijerph6092470
Abstract: The strain Sphingomonas sp. GY2B is a high efficient phenanthrene-degrading strain isolated from crude oil contaminated soils that displays a broad-spectrum degradation ability towards PAHs and related aromatic compounds. This paper reports embedding immobilization of strain GY2B in calcium alginate gel beads and the rapid degradation of phenanthrene by the embedded strains. Results showed that embedded immobilized strains had high degradation percentages both in mineral salts medium (MSM) and 80% artificial seawater (AS) media, and had higher phenanthrene degradation efficiency than the free strains. More than 90% phenanthrene (100 mg·L-1) was degraded within 36 h, and the phenanthrene degradation percentages were >99.8% after 72 h for immobilized strains. 80% AS had significant negative effect on the phenanthrene degradation rate (PDR) of strain GY2B during the linear-decreasing stage of incubation and preadsorption of cells onto rice straw could improve the PDR of embedded strain GY2B. The immobilization of strain GY2B possesses a good potential for application in the treatment of industrial wastewater containing phenanthrene and other related aromatic compounds.
Enantiomerically pure D-phenylglycine production using immobilized Pseudomonas aeruginosa 10145 in calcium alginate beads
Alonso, Fábio O. M.;Antunes, O. A. C.;Oestreicher, Enrique G.;
Journal of the Brazilian Chemical Society , 2007, DOI: 10.1590/S0103-50532007000300011
Abstract: in a preliminary work in our laboratory, a pseudomonas aeruginosa strain was found to have enzymatic activity to convert arylaminonitriles into d-amino acids. this enzymatic activity was increased by induction to produce enantiomerically pure d-phenylglycine using 2-phenyl-2-aminoacetonitrile as starting material. in this work, the best conditions leading to this transformation are described. in order to increase the biocatalyst potential use, cells of pseudomonas aeruginosa 10145 were entrapped in calcium alginate gel beads. two different concentration of sodium alginate were used to immobilize these cells. beads morphology was demonstrated by scanning electron microscopy (sem). the beads with higher porosity, formed with 1.5% (m/v) of sodium alginate led to the best conversion of 2-phenyl-2-aminoacetonitrile into d-phenylglycine (20% of conversion, 3.0 h of reaction enantiomeric excess higher than 98%). recycling was performed in four repeated batch reactions, which proved the biocatalyst activity maintenance.
Kinetic Characterization and Effect of Immobilized Thermostable β-Glucosidase in Alginate Gel Beads on Sugarcane Juice  [PDF]
Keerti,Anuradha Gupta,Vinod Kumar,Ashutosh Dubey,A. K. Verma
ISRN Biochemistry , 2014, DOI: 10.1155/2014/178498
Abstract: A thermostable β-glucosidase was effectively immobilized on alginate by the method of gel entrapment. After optimization of immobilized conditions, recovered enzyme activity was 60%. Optimum pH, temperature, kinetic parameters, thermal and pH stability, reusability, and storage stability were investigated. The and for immobilized β-glucosidase were estimated to be 5.0?mM and 0.64?U/ml, respectively. When comparing, free and immobilized enzyme, change was observed in optimum pH and temperature from 5.0 to 6.0 and 60°C to 80°C, respectively. Immobilized enzyme showed an increase in pH stability over the studied pH range (3.0–10.0) and stability at temperature up to 80°C. The storage stability and reusability of the immobilized β-glucosidase were improved significantly, with 12.09% activity retention at 30°C after being stored for 25?d and 17.85% residual activity after being repeatedly used for 4 times. The effect of both free and immobilized β-glucosidase enzyme on physicochemical properties of sugarcane juice was also analyzed. 1. Introduction β-Glucosidase (β-D-glucoside glucohydrolase; EC is a part of multienzyme cellulase complex, whose synthesis and action are intricately controlled by regulatory mechanisms in the organisms that produce these enzymes. The enzymatic hydrolysis of cellulose involves three types of cellulase activities (cellobiohydrolases, endoglucanases, and β-glucosidases) working in synergy [1, 2]. β-Glucosidases hydrolyze β-D-glycosidic bond to release nonreducing β-D-glucose residue and terminal aglycone. These are widely used in the various biotechnological processes including aroma and flavour enrichment [3], discoloration of fruit juices prevention [4], and organoleptic properties of citrus fruit juices improvement, in which the bitterness is in part due to a glucosidic compound, naringin (4,5,7-trihydroxyflavanone-7-rhamnoglucoside) [5]. β-Glucosidase also acts as a key enzyme in the enzymatic release of aromatic compounds from glucosidic precursors present in fruits and fermentation products [6]. Transglycosylation reactions by β-glucosidase have great importance in wine or beverage industry because of their abilities to improve the aroma [7]. The synthetic activity of β-glucosidase can be used in the preparation of a variety of compounds such as oligosaccharides and glycoconjugates that have potential for use as agrochemicals and drugs. β-Glucosidase, produced intracellularly by many microorganisms, usually shows a broad specificity and also transferase activity [8]. Nevertheless, the applications of enzyme in
Comparison of four supports for adsorption of reactive dyes by immobilized Aspergillus fumigatus beads
WANG Bao-e,HU Yong-you,
WANG Bao-e
,HU Yong-you

环境科学学报(英文版) , 2007,
Abstract: Four materials, sodium carboxymethylcellulose (Na-CMC), sodium alginate (SA), polyvinyl alcohol (PVA), and chitosan (CTS), were prepared as supports for entrapping fungus Aspergillus fumigatus. The adsorption of synthetic dyes, reactive brilliant blue KN-R, and reactive brilliant red K-2BP, by these immobilized gel beads and plain gel beads was evaluated. The adsorption efficiencies of reactive brilliant red K-2BP and reactive brilliant blue KN-R by CTS immobilized beads were 89.1% and 93.5% in 12 h, respectively. The adsorption efficiency by Na-CMC immobilized beads was slightly lower than that of mycelial pellets. But the dye culture mediums were almost completely decolorized in 48 h using the above-mentioned two immobilized beads (exceeding 95%). The adsorption efficiency by SA immobilized beads exceeded 92% in 48 h. PVA-SA immobilized beads showed the lowest adsorption efficiency, which was 79.8% for reactive brilliant red K-2BP and 92.5% for reactive brilliant blue KN-R in 48 h. Comparing the adsorption efficiency by plain gel beads, Na-CMC plain gel beads ranked next to CTS ones. SA and PVA-SA plain gel beads hardly had the ability of adsorbing dyes. Subsequently, the growth of mycelia in Na-CMC and SA immobilized beads were evaluated. The biomass increased continuously in 72 h. The adsorption capacity of reactive brilliant red K-2BP and reactive brilliant blue KN-R by Na-CMC immobilized beads was 78.0 and 86.7 mg/g, respectively. The SEM micrographs show that the surface structure of Na-CMC immobilized bead is loose and finely porous, which facilitates diffusion of the dyes.
Evelina Ivanova, Valentina Chipeva, Iskra Ivanova, Xavier Dousset and Denis Poncelet
Journal of Culture Collections , 2002,
Abstract: Investigations on encapsulation of lactic acid bacteria in alginate beads were carried out. For this purpose a bacteriocin producing strain Enterococcus faecium A 2000 was used. For the production of capsules with a small diameter (0.8-1 mm) an electrostatic generator was applied. To enhance of the capsule stability, the fermentation was performed in modified MRS medium without phospates and with addition of CaCl2 . As a result of the immobilization the bacteriocin production was increased with approximately 50 %, compared with the batch fermentation with free cells. The immobilized cells could be reuses up to three times after filtration and re-suspension in new medium.
Simulation of Enzyme Catalysis in Calcium Alginate Beads  [PDF]
Ameel M. R. Al-Mayah
Enzyme Research , 2012, DOI: 10.1155/2012/459190
Abstract: A general mathematical model for a fixed bed immobilized enzyme reactor was developed to simulate the process of diffusion and reaction inside the biocatalyst particle. The modeling and simulation of starch hydrolysis using immobilized α-amylase were used as a model for this study. Corn starch hydrolysis was carried out at a constant pH of 5.5 and temperature of . The substrate flow rate was ranging from 0.2 to 5.0?mL/min, substrate initial concentrations 1 to 100?g/L. α-amylase was immobilized on to calcium alginate hydrogel beads of 2?mm average diameter. In this work Michaelis-Menten kinetics have been considered. The effect of substrate flow rate (i.e., residence time) and initial concentration on intraparticle diffusion have been taken into consideration. The performance of the system is found to be affected by the substrate flow rate and initial concentrations. The reaction is controlled by the reaction rate. The model equation was a nonlinear second order differential equation simulated based on the experimental data for steady state condition. The simulation was achieved numerically using FINITE ELEMENTS in MATLAB software package. The simulated results give satisfactory results for substrate and product concentration profiles within the biocatalyst bead. 1. Introduction Enzyme immobilization on to supports (or carriers) and their applications as catalysts have grown considerably during the last three decades, and during the last few years have become the most exciting aspects of biotechnology [1–3]. Several methods of enzyme immobilization exist and can be classified into three main categories: carrier binding, cross linking, and entrapment [1]. A number of advantages of enzyme immobilization on to support and several major reasons are the ability to stop the reaction rapidly by removing the enzyme from the reaction solution (or vice versa), products being free of enzyme (especially useful in the food and pharmaceutical industries), reduced effluent disposal problems, suitability for continuous reactor operation, and multiple or respective use of a single batch of enzymes, especially if the enzymes are scarce or expensive, their applicability to continuous processes, and the minimization of pH and substrate-inhibition effects. This has an obvious economic impact and allows the utilization of reactors with high enzyme loads [4]. Enzyme entrapment within a gel matrix is one of the enzyme immobilization ways. In this way, the enzyme is surrounded by a semipermeable membrane. Enzyme support of a specific structure permits the contact between the
Viability and infectivity of an ectomycorrhizal inoculum produced in an airlift bioreactor and immobilized in calcium alginate
Oliveira, Leyza Paloschi de;Rossi, Márcio José;Furigo Júnior, Agenor;Silva Filho, Germano Nunes;Oliveira, Vetúria Lopes de;
Brazilian Journal of Microbiology , 2006, DOI: 10.1590/S1517-83822006000300011
Abstract: the viability and infectivity of an ectomycorrhizal inoculum (isolate ufsc-rh90, rhizopogon nigrescens), produced by submerged cultivation in an airlift bioreactor and immobilized in beads of calcium alginate gel, was studied. inoculum remained 100% viable after 18 months in a 0.85% nacl solution at 8 ± 1oc. mycelium grew from the beads after 48 h when they were placed on a solid culture medium at 25 ± 1oc. viability of pellets of non-immobilized mycelium stored under the same conditions decreased gradually after the third month of storage, reaching 0% by the 12th month. these pellets presented a gradual darkening, which was more intense in those located near the surface of the nacl solution. in culture medium, these dark pellets showed no viability. gel immobilization helps to maintain mycelium viability during storage and offers a physical protection when the inoculum is applied to the planting substrate. after eight months refrigeration, the immobilized inoculum was still able to infect pinus taeda seedlings, colonizing an average of 37% of the root tips when inoculated in the plant growth substrate under greenhouse conditions. this inoculum presents a commercial potential to be produced and applied in forest nurseries.
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