Characterization of lipase fromCandida rugosaentrapped in alginate beads to enhance its thermal stability and recyclability

Abstract

Lipase from Candida rugosa has been immobilized in different formulations of calcium alginate beads, prepared by ionotropic gelation, which differ from each other in CaCl2 concentration and hardening time, to...

A combined experimental and computational approach for the rationalization of the catalytic activity of lipase B from Candida antarctica in water–organic solvent mixtures

“…Hydrolytic activity assay of Candida antarctica lipase type B Catalytic activity was monitored spectrophotometrically with a Hewlett Packard HP 8452A instrument, following the hydrolysis reaction of p-NPA at 348 nm, which corresponds to the isosbestic point p-nitrophenol/p-nitrophenoxide. The procedure was adapted from the literature to this case study: 34 a test tube containing the reaction solution (water-organic solvent mixture at different percentages) was thermostated at a temperature of 37 °C. The enzyme at a concentration of 0.5 mg mL −1 was added to the reaction solution after 15 min so that it reached thermal equilibrium.…”

Prevention of Swelling Phenomenon of Alginate Beads To Improve the Stability and Recyclability of Encapsulated Horse Liver Alcohol Dehydrogenase

“…The operational procedure was adapted from our previous work to this case study. [6] The beads (1.6-1.8 g-1 mg HLADH) were placed in a thermostated reaction vessel containing 9 ml of a substrate solution in pure Tris-HCl buffer (10 mM, pH 8.0) or added with 2 mM calcium chloride. The substrate concentration was 20 mM and 10 mM in the case of cyclohexanol and cyclohexanone, respectively.…”

“…Reactions were performed in pure water since the enzyme was active even in the absence of a buffer solution, thus avoiding the swelling of the beads and the loss of the enzyme. [6] Unfortunately, HLADH needs a buffer solution to react, and then, to obtain an active and stable biocatalyst over time, the phosphate buffer was replaced with Tris-HCl. The oxidation reaction of cyclohexanol to cyclohexanone and the reverse reduction reaction catalyzed by HLADH trapped in the beads were conducted in 10 mM Tris-HCl buffer at pH 8.0.…”

“…Enzyme trapping within alginate beads is a widely used procedure as it is simple, fast, inexpensive, and environmentally sustainable. [6,7] However, some disadvantages are often associated with this support, including low mechanical strength and significant loss of the encapsulated biomolecules due to the swelling behavior caused by the open structure, large pore size, and high hydrophilicity. [8] These disadvantages, therefore, significantly reduce the stability of the biocatalysts, preventing their large-scale application.…”

“…However, if the enzyme is to be used in large‐scale processes, it is extremely important to reduce both the economic and ecological costs of the immobilized catalyst. Enzyme trapping within alginate beads is a widely used procedure as it is simple, fast, inexpensive, and environmentally sustainable [6,7] . However, some disadvantages are often associated with this support, including low mechanical strength and significant loss of the encapsulated biomolecules due to the swelling behavior caused by the open structure, large pore size, and high hydrophilicity [8] .…”