Chitin immobilized

To determine the catalytic activity of chitin-immobilized Amyloglucosidase on the hydrolysis of dextrin, an experiment was conducted in which rate of hydrolysis of dextrin was monitored with the increase of time. To lOOmg of dextrin 2 units of chitin-immobilized... 

Figure 1 Comparison of actitivites of chitin-immobilized and native Amyloglucusidases on dextrin-hydrolysis...

Ouchi, Y., Banba, T., Matsumoto, T., Suzuki, S. and Suzuki, M. (1989) Antitumour activity of chitosan and chitin immobilized 5-fluorouracils through hexamethylene spacers via carbamoyl bonds. J. Bioact. Biocomp. Pol. 4 362-371. 

As an example. Fig. 5.15 shows the kinetics of reaction and inactivation of chitin-immobilized (3-galactosidase at 27.5°C (Illanes et al. 2000). In this case the enzyme is competitively inhibited by the product galactose but not for glucose and inactivation for all enzyme species was modeled according to a two-stage series mechanism... 

CPBR with chitin-immobilized (3-galactosidase (Illanes et al. 1998a) is presented to illustrate enzyme reactor design under modulated thermal inactivation. Diffusional restrictions are in this case negligible, the enzyme is inhibited by the product galactose competitively and neither glucose nor lactose at high concentrations are inhibitors (Illanes et al. 1990), so that Fig. 5.14 simplifies to the scheme in Fig. 5.18. 

Thermal inactivation of chitin-immobilized 3-galactosidase has been adequately described by a two-stage series mechanism with zero residual activity. From a material balance of all enzyme species considering a two-stage series mechanism of inactivation (see Fig. 5.18), from Eq. 5.63 applied to each of the enzyme species, Eq. 5.67 and Eq. 5.75, thermal inactivation of chitin-immobilized enzyme in the bioreactor... 

CPBR behavior under pseudo-steady-state and plug-flow regime is described by the resolution of the system of differential Eqs. 5.76 and 5.79. This model was experimentally validated in a laboratory packed-bed reactor with chitin-immobilized... 

Table 5.5 Temperature Optimization Based on a Cost-Objective Function of Multiple Staggered CPBER with Chitin-Immobilized P-Galactosidase Under Biocatalyst Replacement at 25% of Initial Activity. Operation Conditions Are Those in Table 5.3...

Illanes A, Wilson L, Raiman L (1999) Design of immobilized reactors for the continuous production of fiuctose syrup from whey permeate. Bioproc Eng 21 509-515 Illanes A, Wilson L, TomaseUo G (2000) Temperature optimization for reactor operation with chitin-immobilized lactase under modulated inactivation. Enzyme Microb Technol 27 270-278 Illanes A, Wilson L, TomaseUo G (2001) Effect of modulation of enzyme inactivation on temperature optimization for reactor operation with chitin-immobUized lactase. J Mol Catal B Enzym 1 531-540... 

Jeon, Y.J., Park, P.J., Byun, H.G., Song, B.K., and Kim, S.K. 1998. Production of chitosan oligosaccharides using chitin-immobilized enzyme. Korean J. Biotechnol. Bioeng. 13 147-154. 

Figure 17.27 The EPL process involves a fusion protein containing an intein tag plus a CBD. The fusion protein is captured on an immobilized chitin resin and after removal of contaminating proteins, it is eluted using thiophenol, which cleaves at the thioester bond between the intein and the desired expressed protein. This releases a phenylth-ioester-activated protein that can be used in the native chemical ligation reaction with another peptide containing an N-terminal cysteine residue. Conjugation results in a native amide (peptide) bond formed between them.

Henderson, W., Olsen, G.M., and Bonnington, L.S. (1994) Immobilized phosphines incorporating the chiral biopolymers chitosan and chitin./. Chem. Soc. Comm., 1863-1864. 

Pallavicini et al. (16) utilized a-chymotrypsin immobilized on chitin to catalyze plastein formation from leaf protein hydrolyzates. When analyzed by gel exclusion chromatography, the products were comparable to those produced by soluble enzymes. Modification of Specific Functional Properties... 

Krajewska, B. (2004) Application of chitin-and chitosan-based materials for enzyme immobilizations a review. Enz. Microb. Technol., 35, 126. 

In addition to the novel applications mentioned above, chitosan and chitin have been exploited in numerous areas such as wound dressing, cholesterol control, food stabilization, hair/skin care, and cell/enzyme immobilization. 

Another interesting organic material usually used to immobilize enzymes is chitosan [95, 96]. Chitosan is a poly((1 4)-2-amino-2-deoxy-P-D-glucose) (Fig. 9.5), which is a product of deacetylation of chitin, the second polysaccharide ranked by its prevalence in nature, just after cellulose. 

Microcrystalline chitin has been used as a thickening/gelling agent in the binding, stabilizing, and texturing of food [58]. Chitin is widely used to immobilize enzymes and whole cells enzyme immobilization has applications in the food industry, such as clarification of fruit juices and... 

Cell immobilization Chitosan is preferred over chitin (high DD)... 

Illanes A, Gentina JC, Marchese MP (1988a) Production and stabiUzation of cellulases from Trichoderma reesei. MIRCEN J Appl Microbiol Biotechnol 4 407-414 Illanes A, Zuniga ME, Chamy R et al. (1988b) Immobilization of lactase and invertase on crosslinked chitin. In Moo-Young M (ed). Immobilized enzymes and cells. Elsevier, London, pp 233-249... 

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