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Screening of supports for immobilization of commercial porcine pancreatic lipase
Scherer, Robison;Oliveira, J. Vladimir;Pergher, Sibele;Oliveira, Débora de;
Materials Research , 2011, DOI: 10.1590/S1516-14392011005000079
Abstract: the aim of this work is to report the performance of different supports for the immobilization of commercial porcine pancreatic lipase. the immobilization tests were carried out in several types of accurel, activated alumina, kaolin, montmorillonite, ion exchange resins and zeolites. the characterization of the supports showed differences in terms of specific area and morphology. the characteristics of the supports influenced the amount of enzyme adsorbed, yield of immobilization and esterification activity of the resulting immobilized catalyst. the clays ksf and natural and pillared montmorillonites presented potential for use as support for lipase immobilization in terms of yield and esterification activity. yields of immobilization of 76.32 and 52.01% were achieved for clays ksf and natural montmorillonite, respectively. esterification activities of 754.03, 595.51, 591.88 and 515.71 u.g-1 were obtained for lipases immobilized in accurel mp-100, amberlite xad-2, mordenite and pillared montmorillonite, respectively.
Facile, high efficiency immobilization of lipase enzyme on magnetic iron oxide nanoparticles via a biomimetic coating
Yuhong Ren, Jose G Rivera, Lihong He, Harsha Kulkarni, Dong-Keun Lee, Phillip B Messersmith
BMC Biotechnology , 2011, DOI: 10.1186/1472-6750-11-63
Abstract: A facile method of lipase immobilization was developed in this study, by the use of polydopamine coated magnetic nanoparticles (PD-MNPs). Under optimal conditions, 73.9% of the available lipase was immobilized on PD-MNPs, yielding a lipase loading capacity as high as 429 mg/g. Enzyme assays revealed that lipase immobilized on PD-MNPs displayed enhanced pH and thermal stability compared to free lipase. Furthermore, lipase immobilized on PD-MNPs was easily isolated from the reaction medium by magnetic separation and retained more than 70% of initial activity after 21 repeated cycles of enzyme reaction followed by magnetic separation.Immobilization of enzyme onto magnetic iron oxide nanoparticles via poly-dopamine film is economical, facile and efficient.Lipases (glycerol ester hydrolases E.C.3.1.1.3) are an important group of enzymes which have been widely used in the catalysis of different reactions [1,2]. These enzymes have been applied in chemical and pharmaceutical industrial applications due to their catalytic activity in both hydrolytic and synthetic reactions. However, free lipases are easily inactivated and difficult to recover for reuse. Therefore, especially in large-scale applications, lipases are often immobilized on solid supports in order to facilitate recovery and improve operational stability under a wide variety of reaction conditions. Some lipase immobilization strategies involve the conjugation of lipases via covalent attachment, cross-linking, adsorption and entrapment onto hydrophobic or hydrophilic polymeric and inorganic matrixes [3-5].In recent years, magnetic nanoparticles (MNPs) based on iron oxides, have attracted much interest thanks to their multifunctional properties, such as biocompatibility, superparamagnetism, small size and low toxicity [6]. They have been applied in magnetic resonance imaging (MRI) [7], biosensors [8] and as anti-cancer drugs carriers [9]. Due to their high specific surface area and easy separation from the reaction
Immobilization and Characterization of a Recombinant Thermostable Lipase (Pf2001) from Pyrococcus furiosus on Supports with Different Degrees of Hydrophobicity  [PDF]
Roberta Vieira Branco,Melissa Limoeiro Estrada Gutarra,Denise Maria Guimar?es Freire,Rodrigo Volcan Almeida
Enzyme Research , 2010, DOI: 10.4061/2010/180418
Abstract: We studied the immobilization of a recombinant thermostable lipase (Pf2001 ) from the hyperthermophilic archaeon Pyrococcus furiosus on supports with different degrees of hydrophobicity: butyl Sepabeads and octadecyl Sepabeads. The enzyme was strongly adsorbed in both supports. When it was adsorbed on these supports, the enzyme showed 140 and 237% hyperactivation, respectively. The assessment of storage stability showed that the octadecyl Sepabeads immobilized enzyme showed 100% of residual activity after 30 days of storage. However, the greatest stability at was obtained in butyl Sepabeads immobilized enzyme, which retained 77% activity after 1 hour incubation. The maximum activity of the immobilized preparations was obtained with the pH between 6 and 7, at . Thus, this study achieved a new extremophilic biocatalyst with greater stability, for use in several biotechnological processes. 1. Introduction Carboxylesterases (E.C.3.1.1.1) and lipases (E.C.3.1.1.3) are enzymes that are classified as hydrolases, which in aqueous media catalyze the hydrolysis of ester bonds, generating alcohol and carboxylic acids. These enzymes catalyze various reactions, which sometimes have high chemo- and enantioselectivity, which explains their use in several sectors, such as the food, paper, textile, and detergent industries, wastewater treatment, fine chemistry, and pharmaceutical synthesis [1–5]. A number of lipases present a polypeptide chain called “lid” covering the active site and may exist in two different forms: one of them, where the active site of the lipase is isolated from the reaction medium by lid (closed form); the other conformation, presenting the lid displaced and the active centre exposed to the reaction medium (open form). This conformational change from closed to open form causes an increasing in enzyme activity when lipases are exposed to insoluble substrates, called “interfacial activation” [6]. This structural phenomenon was used to differentiate lipases from esterases which do not show this activation. However, some studies showed that neither all lipases presented interfacial activation, nor lid, and interestingly some lipases showed interfacial activation only for specific substrates. So these characteristics are not sufficient to differentiate lipases from esterases. Although there are works with others approaches to differentiate these enzymes [7], the definition of lipases more accepted is lipases are carboxylesterases that catalyze the hydrolysis (and synthesis) of ester bonds with long chain fatty acids (C 10) [8]. This mechanism of action
Immobilization and catalytic properties of lipase on chitosan for hydrolysis and esterification reactions
Pereira, E.B.;Zanin, G.M.;Castro, H.F.;
Brazilian Journal of Chemical Engineering , 2003, DOI: 10.1590/S0104-66322003000400002
Abstract: the objective of this study was to evaluate the immobilization of lipase on a chitosan support by physical adsorption, aiming at its application in hydrolytic and synthetic reactions. two types of chitosan (flakes and porous) were used for immobilizing lipase from a microbial source (candida rugosa) and animal cells (porcine pancreas). the best results for recovery of total activity after immobilization were obtained for microbial lipase and porous chitosan beads. this set was selected for further immobilization studies, including full characterization of the immobilized derivative in aqueous and organic media. in aqueous medium, the operational and thermal stabilities of this preparation were quantified. in organic medium, the direct synthesis of n-butyl butyrate in organic solvent was chosen as a model reaction. the influence of several parameters, such as temperature, initial butyric acid concentration and amount of enzyme in the reaction system, was analyzed. production of n-butyl butyrate was optimized and an ester yield response equation was obtained, making it possible to predict ester yields from known values of the three main factors. use of this immobilized preparation was extended to the direct esterification of a large range of carboxylic acids (from c2 to c12) with a variety of alcohols (from c2 to c10).
Immobilization and catalytic properties of lipase on chitosan for hydrolysis and esterification reactions  [cached]
Pereira E.B.,Zanin G.M.,Castro H.F.
Brazilian Journal of Chemical Engineering , 2003,
Abstract: The objective of this study was to evaluate the immobilization of lipase on a chitosan support by physical adsorption, aiming at its application in hydrolytic and synthetic reactions. Two types of chitosan (flakes and porous) were used for immobilizing lipase from a microbial source (Candida rugosa) and animal cells (porcine pancreas). The best results for recovery of total activity after immobilization were obtained for microbial lipase and porous chitosan beads. This set was selected for further immobilization studies, including full characterization of the immobilized derivative in aqueous and organic media. In aqueous medium, the operational and thermal stabilities of this preparation were quantified. In organic medium, the direct synthesis of n-butyl butyrate in organic solvent was chosen as a model reaction. The influence of several parameters, such as temperature, initial butyric acid concentration and amount of enzyme in the reaction system, was analyzed. Production of n-butyl butyrate was optimized and an ester yield response equation was obtained, making it possible to predict ester yields from known values of the three main factors. Use of this immobilized preparation was extended to the direct esterification of a large range of carboxylic acids (from C2 to C12) with a variety of alcohols (from C2 to C10).
Enzymatic Synthesis of Isopropyl Acetate by Immobilized?? Bacillus cereus Lipase in Organic Medium  [PDF]
Madan Lal Verma,Wamik Azmi,Shamsher Singh Kanwar
Enzyme Research , 2011, DOI: 10.4061/2011/919386
Abstract: Selective production of fragrance fatty acid ester from isopropanol and acetic acid has been achieved using silica-immobilized lipase of Bacillus cereus MTCC 8372. A purified thermoalkalophilic extracellular lipase was immobilized by adsorption onto the silica. The effects of various parameters like molar ratio of substrates (isopropanol and acetic acid; 25 to 100?mM), concentration of biocatalyst (25–125?mg/mL), reaction time, reaction temperature, organic solvents, molecular sieves, and initial water activity were studied for optimal ester synthesis. Under optimized conditions, 66.0?mM of isopropyl acetate was produced when isopropanol and acetic acid were used at 100?mM: 75?mM in 9?h at 55°C in -heptane under continuous shaking (160?rpm) using bound lipase (25?mg). Addition of molecular sieves (3????×?1.5?mm) resulted in a marked increase in ester synthesis (73.0?mM). Ester synthesis was enhanced by water activity associated with pre-equilibrated saturated salt solution of LiCl. The immobilized lipase retained more than 50% of its activity after the 6th cycle of reuse. 1. Introduction Environment-friendly biocatalysts are now rapidly substituting the conventional harsh chemical methods for the synthesis of important fatty acid esters used in many chemicals, medicines, cosmetics, and foods [1–5]. The attention towards tremendous use of microbial lipase (triacylglycerol acylhydrolase, EC 3.1.1.3) was exploited in the past decade leading to the easy hydrolysis/synthesis of esters at ambient condition with an advantage of precise selectivity. Such reactions mediated by biocatalysts have advantages like mild reaction conditions, one step synthesis without protection and deprotection steps, and easy application to food processing [6–8]. A lipase catalyzes a reversible reaction and the direction and equilibrium of the reaction is determined by the activities of the substrates, products, temperature, and pressure [9]. Enzymes immobilization is the inherent advantage to isolate the biocatalyst from the reaction product and reuse it in order to increase the process productivity [10–12]. Immobilization by adsorption has been most widely used for immobilization of various enzymes [13, 14]. Highly porous inorganic matrices such as silica aerogels with differing balances of hydrophobic and hydrophilic functionalities have been successfully used for the immobilization of enzymes. Silica aerogels can be considered as “solid” solvent for the enzymes that are able to provide hydrophobic/hydrophilic characteristics differing from those prevailing in the liquid
Screening of Supports for the Immobilization of -Glucosidase  [PDF]
Joelise de Alencar Figueira,Fernanda Furlan Gon?alves Dias,Hélia Harumi Sato,Pedro Fernandes
Enzyme Research , 2011, DOI: 10.4061/2011/642460
Abstract: A set of supports were screened for the immobilization of a partially purified extract of β-glucosidase from Aspergillus sp. These supports, namely, Eupergit, Amberlite, alginate, gelatin, polyvinyl alcohol- (PVA-) based matrices (Lentikats), and sol-gel, have proved effective for the implementation of some other enzyme-based processes. The initial criterion for selection of promising supports prior to further characterization relied on the retention of the catalytic activity following immobilization. Based on such criterion, where immobilization in sol-gel and in Lentikats outmatched the remaining approaches, those two systems were further characterized. Immobilization did not alter the pH/activity profile, whereas the temperature/activity profile was improved when sol-gel support was assayed. Both thermal and pH stability were improved as a result of immobilization. An increase in the apparent (Michaelis constant) was observed following immobilization, suggesting diffusion limitations. 1. Introduction β-Glucosidases (β-D-glucoside glucohydrolases, EC 3.2.1.21) are enzymes that transfer a glycosyl group between oxygen nucleophiles. They are, therefore, accountable for the hydrolysis of β-glycosidic linkages in amino-, alkyl-, or aryl-β-D-glucosides, cyanogenic glycosides, and di- and short chain oligo-saccharides [1, 2]. β-glucosidases can be used in the production of aromatic compounds, in the stabilization of juices and beverages, and in the improvement of the organoleptic properties of food and feed products; they are also used in biomass degradation, in the production of fuel ethanol from cellulosic agricultural residues, and in the synthesis of alkyl- and arylglycosides from natural polysaccharides or their derivatives and alcohols, by reversed hydrolysis or trans-glycosylation, leading to products with applications in pharmaceutical, cosmetic, and detergent industries [1, 3–5]. The immobilization of β-glucosidase in a solid carrier offers the prospect of cost savings and widens the flexibility of process design, by enabling continuous operation (or multiple cycles of batch operation on a drain-and-fill basis) and simplifying downstream processing. Enzyme immobilization also allows for a high-biocatalyst load within the bioreactor, thus leading to high-volumetric productivities [6, 7]. Guidelines for cost analysis of bioconversion processes have been recently suggested [8]. In the present work, several immobilization methods were screened as suitable approaches for the immobilization of a β-glucosidase from an Aspergillus sp. Specifically,
Covalent immobilization of lipase from Candida rugosa on Eupergit
Bezbradica Dejan I.,?orovi? Jasmina J.,Prodanovi? Radivoje M.,Milosavi? Nenad B.
Acta Periodica Technologica , 2005, DOI: 10.2298/apt0536179b
Abstract: An approach is presented for the stable covalent immobilization of Upase from Candida rugosa on Eupergit with a high retention of hydrolytic activity. It comprises covalent bonding via lipase carbohydrate moiety previously modified by periodate oxidation, allowing a reduction in the involvement of the enzyme functional groups that are probably important in the catalytic mechanism. The hydrolytic activities of the lipase immobilized on Eupergif1 by two conventional methods (via oxirane group and via glutaralde-hyde) and with periodate method were compared. Results of lipase assays suggest that periodate method is superior for lipase immobilization on Eupergit among methods applied in this study with respect to both, yield of immobilization and hydrolytic activity of the immobilized enzyme.
Carbon Nanotubes as Supports for Inulinase Immobilization  [PDF]
Tais B. Garlet,Caroline T. Weber,Rodrigo Klaic,Edson L. Foletto,Sergio L. Jahn,Marcio A. Mazutti,Raquel C. Kuhn
Molecules , 2014, DOI: 10.3390/molecules190914615
Abstract: The commercial inulinase obtained from Aspergillus niger was non-covalently immobilized on multiwalled carbon nanotubes (MWNT-COOH). The immobilization conditions for the carbon nanotubes were defined by the central composite rotational design (CCRD). The effects of enzyme concentration (0.8%–1.7% v/v) and adsorbent:adsorbate ratio (1:460–1:175) on the enzyme immobilization were studied. The adsorbent:adsorbate ratio variable has positive effect and the enzyme concentration has a negative effect on the inulinase immobilization (U/g) response at the 90% significance level. These results show that the lower the enzyme concentration and the higher the adsorbent:adsorbate ratio, better is the immobilization. According to the results, it is possible to observe that the carbon nanotubes present an effective inulinase adsorption. Fast adsorption in about six minutes and a loading capacity of 51,047 U/g support using a 1.3% (v/v) inulinase concentration and a 1:460 adsorbent:adsorbate ratio was observed. The effects of temperature on the immobilized enzyme activity were evaluated, showing better activity at 50 °C. The immobilized enzyme maintained 100% of its activity during five weeks at room temperature. The immobilization strategy with MWNT-COOH was defined by the experimental design, showing that inulinase immobilization is a promising biotechnological application of carbon nanotubes.
Immobilization of biomolecules on the surface of inorganic nanoparticles for biomedical applications
Zhi-Cai Xing, Yongmin Chang and Inn-Kyu Kang
Science and Technology of Advanced Materials , 2010,
Abstract: Various inorganic nanoparticles have been used for drug delivery, magnetic resonance and fluorescence imaging, and cell targeting owing to their unique properties, such as large surface area and efficient contrasting effect. In this review, we focus on the surface functionalization of inorganic nanoparticles via immobilization of biomolecules and the corresponding surface interactions with biocomponents. Applications of surface-modified inorganic nanoparticles in biomedical fields are also outlined.
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