Immobilization of Pancreatic Lipase on Chitin and Chitosan

Abstract

In this study, porcine pancreatic lipase (EC 3.1.1.3) was immobilized on chitin and chitosan by adsorption and subsequent crosslinking with glutaraldehyde, which was added before (conjugation) or after (crosslinking) washing unbound proteins. Conjugation proved to be the better method for both supports. The properties of free and immobilized enzymes were also investigated and compared. The results showed that the pH optimum was shifted from 8.5 to 9.0 for both the immobilized enzymes. Also, the optimum temperature was shifted from 30 to 40 degrees C for chitin-enzyme and to 45 degrees C for chitosan-enzyme conjugates. The immobilization efficiency is low, but the immobilized enzymes have good reusability and stability (storage and operational). Besides these properties, the immobilized lipases were also suitable for catalyzing esterification reactions of fatty acids and fatty alcohols, both with a medium chain length. According to our results, esterification activities of immobilized lipases were two- and four-fold higher for chitosan- and chitin-enzyme, than for the free enzyme, respectively. The immobilization procedure shows a great potential for commercial applications of the immobilized lipase, a relatively low cost commercial enzyme.

Catalytic and Operational Stability of Acidic Proteases from Monterey Sardine (Sardinops sagax caerulea) Immobilized on a Partially Deacetylated Chitin Support

“…Before immobilization, 0.01 g of support was equilibrated in 3 mL of 0.05 M phosphate buffer (pH 7) for 20 min at 25C (Kılınc¸et al 2006). Before immobilization, 0.01 g of support was equilibrated in 3 mL of 0.05 M phosphate buffer (pH 7) for 20 min at 25C (Kılınc¸et al 2006).…”

“…Various studies have demonstrated that covalent and noncovalent immobilization of enzymes onto chitosan based supports have a positive effect on the optimum temperature and thermal stability of immobilized biocatalysts (Gomes et al 2004;Kılınc¸et al 2006;Alloue et al 2008;Kumar et al 2009). The optimum temperature of immobilized proteases in the present study, shifted to a higher value than that of free proteases (Fig.…”

“…Uniform sized particles of partially deacetylated chitin flakes (PDCHNF) were obtained by sieving the flakes through a 2 mm mesh. Before immobilization, 0.01 g of support was equilibrated in 3 mL of 0.05 M phosphate buffer (pH 7) for 20 min at 25C (Kılınc¸et al 2006). Later, PDCHNF were activated with the corresponding concentration of STPP by stirring at 150 rpm and 30C for 1 h. Active supports were washed thoroughly with water and contacted with 3 mL of semipurified sardine acidic proteases at 4C for 2 h while stirring at 100 rpm (Sangeetha and Abraham 2008).…”

Production of biodiesel using lipase encapsulated in κ-carrageenan

“…This was confirmed by the protein assay performed on the aqueous phase (KCl solution). But, the agitation in the collection flask is necessary to keep the capsules (Macario et al 2009;Kılınç et al 2006;Dizge et al 2008;). The immobilization efficiency can be increased by using a hybrid matrix (κ-carrageenan crosslinked with glutaraldehyde).…”

3D Chitin Scaffolds from the Marine Demosponge Aplysina archeri as a Support for Laccase Immobilization and Its Use in the Removal of Pharmaceuticals

“…Meanwhile, marine demosponges of the order Verongiida have been recognized as a renewable source of uniquely pre-structured 3D chitinous scaffolds [20][21][22][23][24][25][26][27][28] which have found applications in tissue engineering [6,21,[29][30][31][32][33][34], drug release [35], the development of hybrid materials [36][37][38][39][40], and environmental science [41,42]. Chitin of invertebrate origin has previously been studied by researchers in protein immobilization as a matrix for the immobilization of enzymes [43][44][45][46][47][48], including lipases [49,50] and papain [51]. However, in this study we investigated the ability of a unique, ready-to-use 3D chitinous scaffold isolated from the marine demosponge Aplysina archeri ( Figure 1) to immobilize laccase as a selected enzyme, and an innovative application of this unique system in the removal of tetracycline by simultaneous adsorption and catalytic conversion.…”