Immobilization starch

The Turing mechanism requires that the diffusion coefficients of the activator and inlribitor be sufficiently different but the diffusion coefficients of small molecules in solution differ very little. The chemical Turing patterns seen in the CIMA reaction used starch as an indicator for iodine. The starch indicator complexes with iodide which is the activator species in the reaction. As a result, the complexing reaction with the immobilized starch molecules must be accounted for in the mechanism and leads to the possibility of Turing pattern fonnation even if the diffusion coefficients of the activator and inlribitor species are the same 62. 

Aging of gelatinized starch was studied by cross-relaxation NMR method [99]. Relatively immobile starch components increased and components with liquid-like mobility decreased during aging. Two spectral components were observed in cross-relaxation spectra. According to the theory mentioned above(5.5.1.), the broader one correlates with the degree of crystallinity and the narrower one with starch chains having mobility intermediate between... 

Sodium chlorite oxidation of com and rice starches is recommended for the production of textile sizes (101) and oxidized starch is recommended as a hardening agent in the immobilization of microbial cells within gelatin (102). 

P-amylase, and debranching enzymes. Conversion of D-glucose to D-fmctose is mediated by glucose isomerase, mosdy in its immobilized form in columns. Enzymic degradation of starch to symps has been well reviewed (116—118), and enzymic isomerization, especially by immobilized glucose isomerase, has been fiiUy described (119) (see Syrups). 

In the early years of the chemical industry, use of biological agents centered on fermentation (qv) techniques for the production of food products, eg, vinegar (qv), cheeses (see Milk and milk products), beer (qv), and of simple organic compounds such as acetone (qv), ethanol (qv), and the butyl alcohols (qv). By the middle of the twentieth century, most simple organic chemicals were produced synthetically. Fermentation was used for food products and for more complex substances such as pharmaceuticals (qv) (see also Antibiotics). Moreover, supports were developed to immobilize enzymes for use in industrial processes such as the hydrolysis of starch (qv) (see Enzyme applications). 

Fig. 24. Kinetics of add inactivation of a-amylase (Bac. subtilis) in solution (/, 2) and immobilized on Biocarb (3) 1) pH 2 2) and 3) pH 4. A/A0 is the value of relative enzymatic activity (compared to the initial activity A0 before inactivation), substrate — starch...

Abraham TE, Jamuna R, Bansilal CV, Ramakrishna SV (1991) Continuous synthesis of glucoamylase by immobilized fungal mycelium of Aspergillus niger. Starch-Starke 43 113-116... 

Adsorption of azo dyes by the biomass is considered as the first step of their biological reduction [39]. Because of adsorption, the dye is concentrated onto the biomass until its saturation the amount of adsorbed dye is then proportional to the amount of biomass [4CM-2]. Steffan et al. [43] observed that 68% Ethyl Orange was rapidly adsorbed on a microbial consortium immobilized in alginate beads, but only after the addition of glucose or starch the dye was effectively degraded. 

A critical consideration in the development of biocatalytic systems is the form in which the enzyme or enzyme system is going to be used. There are two general approaches. One is to use isolated enzymes. If these are inexpensive, they can be used as disposable biocatalysts, as is the case for glucose isomerase, ° which is the key biocatalyst in the production of high-fructose corn syrups from starch, or the lipases and proteases that are present in detergents. Alternatively, if enzymes are expensive to produce, they can be immobilized and used repeatedly by recovering the enzyme particles after each use. 

Takaori M, Fukui A. Treatment of massive hemorrhage with liposome encapsulated human hemoglobin (NRC) and hydroxyethyl starch (HES) in beagles. Art Cells Blood Substit Immobil Biotechnol 1996 24 643. 

Several variations on these production methods also exist, such as the use of immobilized CGTase (2i, 22), continuous ultrafiltration 23) and the use of isoamylase to increase CD yield. Variations of purification methods include the addition of glucoamylase to degrade non-CD starch hydrolysates to simply separation and the use of various S3mthetic ion exchange resins in chromatographic separations 24-26) and acuity columns (27),... 

W. II. Pitcher Design and Operation of Immobilized Enzyme Reactors. - S. A Barker Biotechnology of Immobilized Multienzyme Systems. - R. A Messing Carriers for Immobilized Biologically Active Systems. -P. Brodelius Industrial Applications of Immobilized Biocatalysts. - B. Solomon Starch Hydrolysis by Immobilized Enzymers. 

In the first section of this book, the brief introduction about biochemical engineering is given in chapter 1. The second chapter deals with basics of enzyme reaction kinetics. The third chapter deals with an important aspect in enzyme bioprocess i.e. immobilization of enzyme and its kinetics. Chapter 4 is concerned about the industrial bioprocess involving starch and cellulose. 

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