Entrapment of chemical derivatives of glycoamylase in calcium alginate gels

“…[2] For this purposes, enzymes have been immobilized onto solid supports materials, in order to improve the reusability properties of enzymes. [3] There have been intensive works to immobilize amyloglucosidase onto various matrices by using different methods such as, adsorption onto magnetic polystyrene beads [4], activated charcoal [2], macrostructured carbonized ceramics [5] and nonporous polystyrene/poly(sodium styrene sulfonate) microspheres [6]; covalent binding to polyglutaraldehyde-activated gelatin [7], macroporous poly(GMA-co-EGDMA) [3], magnetic nanoparticles [8]; and entrapment in alginate [9] and LentiKats®. [10] Enzymes have superior properties for industrial applications such as; they can catalyze the reactions under mild conditions with very high activity, also they have high enantio-and regio-selectivity and specificity towards their substrates.…”

Section: Introductionmentioning

confidence: 99%

Immobilization of amyloglucosidase onto macroporous cryogels for continuous glucose production from starch

Uygun

Akduman

Ergönül

et al. 2015

Journal of Biomaterials Science, Polymer Edition

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Poly(methyl methacrylate-glycidyl methacrylate) [Poly(MMA-GMA)] cryogels were synthesized using monomers of methylmethacrylic acid and epoxy group bearing GMA via radical cryopolymerization technique. Synthesized cryogels were used for the immobilization of amyloglucosidase to the cryogel surface using epoxy chemistry. Characterizations of the free and immobilized amyloglucosidase were carried out by comparing the optimum and kinetic parameters of enzymes. For this, pH and temperature profiles of free and immobilized preparation were studied and, it was found that, optimum pH of enzyme was not change upon immobilization (pH 5.0), while optimum temperature of the enzyme shifted 10 °C to warmer region after immobilization (optimum temperatures for free and immobilized enzyme were 55 and 65 °C, respectively). Kinetic parameters of free and immobilized enzyme were also investigated and Km values of free and immobilized amyloglucosidase were found to be 2.743 and 0.865 mg/mL, respectively. Vmax of immobilized amyloglucosidase was found to be (0.496 µmol/min) about four times less than that of free enzyme (2.020 µmol/min). Storage and operational stabilities of immobilized amyloglucosidase were also studied and it was showed that immobilized preparation had much more stability than free preparation. In the present work, amyloglucosidase immobilized poly(MMA-GMA) cryogels were used for continuous glucose syrup production from starch for the first time. Efficiency of immobilized enzyme was investigated and released amount of glucose was found to be 2.54 mg/mL at the end of the 5 min of hydrolysis. The results indicate that the epoxy functionalized cryogels offer a good alternative for amyloglucosidase immobilization applications with increased operational and thermal stability, and reusability. Also, these cryogels can be used for immobilization of other industrially valuable enzymes beyond amyloglucosidase.

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“…Hagerdal & Mosbach (1981) covalently bound P-glucosidase to alginate, then entrapped the modified enzyme and yeast cells in calcium alginate to produce ethanol from cellobiose. Similarly Svensson & Ottesen (1981) increased the molecular size of glucoamylase by coupling it to soluble dextran before coimmobilizing it in alginate with yeast cells.…”

Section: Immobilized Cells As Sources O F Multi-enzyme Systems (A) Ethanol Productionmentioning

confidence: 99%

Immobilized cells

Bucke

Brown²

1983

Phil. Trans. R. Soc. Lond. B

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Cells of microbes and of higher organisms may be immobilized by a number of methods for a variety of purposes. Although the study of cell immobilization is comparatively novel, the methods that have been developed are very effective and there are few indications that further, greatly superior techniques are likely to evolve. Cells are best immobilized by aggregation, by adsorption onto a support material or by entrapment within gels, of which the natural polysaccharides K-carrageenan and calcium alginate have proved the most useful. Aggregation of cells usually involves heat treatment or chemical cross-linkage and causes total loss of cell viability. It is most suitable for the immobilization of cells so as to contain a single enzymic activity: many of the commercial preparations of glucose isomerase consist of aggregated cells. Adsorption of cells to surfaces is a gentle and simple technique: efficient immobilization is aided by the correct choice of pore size in the support material. Cell viabilities and activities are retained but adsorbed cells may be removed from supports fairly readily. Entrapment within gels allows the retention of cell viability and activity and by supplying full growth media, cells can be made to multiply within the beads of gel, giving very high cell densities. Polyacrylamide has been used satisfactorily for cell entrapment but has been superseded in industrial processes by K-carrageenan or calcium alginate. Industrial processes known to employ immobilized cells include the production of L-malic acid and L-aspartic acid and various steroid conversions. Very many other processes using immobilized cells have been studied at the academic level. Immobilization in polysaccharide gels, in particular, sometimes gives unexpected properties of longevity or activity to cells. These phenomena are largely unexplained but may be due to the gel material’s influencing the chemical composition of the immediate environment of the cells. The use of immobilized cells has not yet made a large impact on the fermentation industries but these are early days in the development of new technology and it is to be expected that processes involving immobilized cells will find wider industrial use in the near future.

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Entrapment of chemical derivatives of glycoamylase in calcium alginate gels

Cited by 16 publications

References 28 publications

Calcium-induced gelation of alginic acid and pH-sensitive reswelling of dried gels.

Calcium-induced gelation of alginic acid and pH-sensitive reswelling of dried gels.

Immobilization of amyloglucosidase onto macroporous cryogels for continuous glucose production from starch

Immobilized cells

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