02517nas a2200217   4500008004100000022001400041245021100055210006900266260007100335300001400406490000700420520157400427100001902001700003102020700002402051700002202075700002402097700003002121700002502151856012302176       2010                        eng d  a0743-746300aAdsorption induced enzyme denaturation: the role of polymer hydrophobicity in adsorption and denaturation of alpha-chymotrypsin on allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymers0 aAdsorption induced enzyme denaturation the role of polymer hydro  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJAN  a1096-11060 v263 a<p>Effects of changes in hydrophobicity of polymeric support oil structure and activity of alpha-chymotrypsin (E.C.3.4.21.1) have been studied with copolymers of allyl glycidyl ether (AGE) and ethylene glycol dimethacrylate (EGDM) with increasing molar ratio of EGDM to AGE (cross-link density 0.05 to 1.5). The enzyme is readily adsorbed front aqueous buffer at room temperature following Langmuir adsorption isotherms in unexpectedly large amounts (25% w/w). Relative hydrophobicity of the copolymers has been assessed by studying adsorption of naphthalene and Fmoc-methionine by the series of copolymers from aqueous solutions. Polymer hydrophobicity appears to increase linearly oil increasing cross-link density from 0.05 to 0.25. Further increase in cross-link density Causes a decrease in naphthalene binding but has little effect on binding of Fmoc-Met. Binding of alpha-chymotrypsin to these copolymers follow the trend for Fmoc-methionine binding, rather than naphthalene binding, indicating involvement of polar interactions along with hydrophobic interactions during binding of protein to the polymer. The adsorbed enzyme undergoes extensive denaturation (ca. 80%) with loss of both tertiary and secondary structure on contact with the copolymers as revealed by fluorescence, CID and Raman spectra of the adsorbed protein. Comparison of enzyme adsorption behavior with Eupergit C, macroporous Amberlite XAD-2, and XAD-7 Suggests that polar interactions of the EGDM ester functional groups with the protein play a significant role in enzyme denaturation.</p>1 aLahari, Challa1 aJasti, Lakshmi, Swarnalath1 aFadnavis, Nitin, W.1 aSontakke, Kalpana1 aIngavle, Ganesh, C.1 aDeokar, Sarika, Babasaheb1 aPonrathnam, Surendra  uhttps://library.ncl.res.in/content/adsorption-induced-enzyme-denaturation-role-polymer-hydrophobicity-adsorption-and-002723nas a2200325   4500008004100000022001400041245019400055210006900249260007300318300001200391490000700403520146800410653003301878653001501911653002601926653002501952653002501977653001702002653003502019653002602054653001202080100001802092700003102110700002002141700002402161700002902185700003002214700002502244856012802269       2012                        eng d  a0927-776500aAdsorption induced enzyme denaturation: the role of protein surface in adsorption induced protein denaturation on allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymers0 aAdsorption induced enzyme denaturation the role of protein surfa  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcFEB  a184-1900 v903 a<p>The effects of protein size on adsorption and adsorption-induced denaturation of proteins on copolymers of allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) have been studied. Different responses were observed for the amount of protein adsorbed and denatured on the polymer surface for different proteins (trypsin, alchol dehydrogenase from baker's yeast (YADH), glucose dehydrogenase (GDH) from Gluconobacter cerinus, and alkaline phosphates from calf intestinal mucosa (CIAP). Protein adsorption on the copolymer with 25% crosslink density (AGE-25) was dependent not only on the size of the protein but also on the presence of glycoside residues on the protein surface. Adsorption and denaturation of proteins follows the order YADH &gt; trypsin &gt; GDH &gt;&gt; CIAP although the molecular weights of the proteins follow the order YADH &gt; CIAP &gt; GDH &gt; trypsin. The lack of correlation between amount of adsorbed protein and its molecular weight was due to the presence of glycoside residues on CIAP and GDH which protect the enzyme surface from denaturation. Enzyme stabilities in aqueous solutions of 1-cyclohexyl-2-pyrrolidinone (CHP) correlate well with the trend in denaturation by the copolymer, strongly suggesting that hydrophobic interactions play a major role in protein binding and the mechanism of protein denaturation is similar to that for water-miscible organic solvents. (C) 2011 Elsevier B.V. All rights reserved.</p>10a1-Cyclohexyl-2-pyrrolidinone10aAdsorption10aAlcohol dehydrogenase10aAlkaline phosphatase10aallyl glycidyl ether10aDenaturation10aethylene glycol dimethacrylate10aGlucose dehydrogenase10aTrypsin1 aThudi, Lahari1 aJasti, Lakshmi, Swarnalath1 aSwarnalatha, Y.1 aFadnavis, Nitin, W.1 aMulani, Khudbudin, Baban1 aDeokar, Sarika, Babasaheb1 aPonrathnam, Surendra  uhttps://library.ncl.res.in/content/adsorption-induced-enzyme-denaturation-role-protein-surface-adsorption-induced-protein-003073nas a2200289   4500008004100000022001400041245010500055210006900160260007300229300001000302490000700312520198800319653002502307653002302332653003502355653002602390653002102416653003202437100001802469700003102487700002502518700002402543700002902567700003002596700002502626856013202651       2012                        eng d  a1381-117700aEnzyme immobilization on epoxy supports in reverse micellar media: prevention of enzyme denaturation0 aEnzyme immobilization on epoxy supports in reverse micellar medi  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcJAN  a54-620 v743 a<p>Immobilization of enzymes such as alpha-chymotrypsin (EC 3.4.21.1), yeast alcohol dehydrogenase (YADH) from Saccharomyces cerevisiae (EC 1.1.1.1) and glucose dehydrogenase (GDH) from Gluconobacter cerinus (EC 1.1.1.119) has been carried out. Copolymers of allyl glycidyl ether (AGE) crosslinked with 25% ethylene glycol dimethacrylate (EGDM) (25 mg, dry wt) were contacted with the enzymes solubilized in reverse micellar media (0.5-5 mg/mL)(overall) of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) salt in isooctane, and cetyl trimethylammonium bromide (CTAB) in chloroform-isooctane (50:50, v/v). Although the enzymes are readily denatured (&gt;90%) after adsorption on the copolymer in aqueous buffers, no such adsorption-induced denaturation takes place in reverse micelles. alpha-Chymotrypsin is remarkably stable in AOT reverse micelles when 0.025 M citrate buffer of pH 9.0 containing 2 mM CaCl2 is used in the water pools instead of Tris-HCl buffer of pH 8.5. It was possible to achieve enzyme concentration of 5 mg/mL in 0.3 M AOT at molar ratio of water to surfactant, (W-0), 30 and to obtain alpha-chymotrypsin loading of 20 mg/g of copolymer. The recovered enzyme solution can be reused with a fresh batch of polymer after supplementing the depleted solution. The immobilized enzyme exhibits excellent stability in aqueous buffers at room temperature and can be recycled several times. YADH is stable in both AOT and CTAB reverse micelles while GDH is stable only in CTAB reverse micelles containing 0.05 M Tris-HCI buffer of pH 8.5. Interestingly, the combination of YADH (2.5 mg/g) and GDH (0.5 mg/g) co-immobilized on the copolymer using CTAB-chloroform-isooctane system can be used for regeneration and recycle of NADPH at least 50 times as exemplified by complete reduction of a prochiral ketoester, ethyl 4-phenyl-2,4-dioxobutyrate (10 mM) to ethyl (R)-2-hydroxy-4-phenylbutyrate (HPB ester) using NADPH (0.2 mM). (C) 2011 Elsevier B.V. All rights reserved.</p>10aallyl glycidyl ether10aalpha-Chymotrypsin10aethylene glycol dimethacrylate10aGlucose dehydrogenase10aReverse micelles10aYeast alcohol dehydrogenase1 aThudi, Lahari1 aJasti, Lakshmi, Swarnalath1 aSwarnalatha, Yalangi1 aFadnavis, Nitin, W.1 aMulani, Khudbudin, Baban1 aDeokar, Sarika, Babasaheb1 aPonrathnam, Surendra  uhttps://library.ncl.res.in/content/enzyme-immobilization-epoxy-supports-reverse-micellar-media-prevention-enzyme-denaturation-001977nas a2200265   4500008004100000022001400041245021300055210006900268260007900337300001000416490001000426520089900436653002301335653002501358653002001383653001901403653001801422100003101440700002401471700002401495700001901519700001901538700002501557856012901582       2014                        eng d  a0141-022900aCo-immobilized glucose oxidase and beta-galactosidase on bovine serum albumin coated allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymer as a biosensor for lactose determination in milk0 aCoimmobilized glucose oxidase and betagalactosidase on bovine se  a360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USAbELSEVIER SCIENCE INCcOCT  a67-730 v64-653 a<p>Bovine serum albumin (BSA) was adsorbed on allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymer with 25% crosslink density (AGE-25) at pH 8.0 (16% w/w). The amino, thiol and carboxylic acid functional groups available on protein coated surface were utilized for covalent immobilization of glucose oxidase and beta-galactosidase, both independently, and in a step-wise manner on the same matrix, with no more than 10% loss of enzyme activity during immobilization. Glutaraldehyde cross-linking after immobilization provided stable enzyme preparations. The pH-optima of the immobilized enzymes were similar to those for free enzyme but their thermal stability was vastly improved. The co-immobilized enzyme support was used as a biosensor for determination of lactose in milk with excellent reproducibility and reusability. (C) 2014 Elsevier Inc. All rights reserved.</p>10abeta-Galactosidase10aBovine serum albumin10aGlucose oxidase10aImmobilization10aLactose assay1 aJasti, Lakshmi, Swarnalath1 aDola, Sandhya, Rani1 aFadnavis, Nitin, W.1 aAddepally, Uma1 aDaniels, Siona1 aPonrathnam, Surendra  uhttps://library.ncl.res.in/content/co-immobilized-glucose-oxidase-and-beta-galactosidase-bovine-serum-albumin-coated-allyl-002020nas a2200265   4500008004100000022001400041245010300055210006900158260007300227300001200300490000800312520108200320653001501402653001701417653001901434653001201453653001201465100003101477700002401508700001901532700001901551700003001570700002501600856012901625       2014                        eng d  a0927-776500aComparison of polymer induced and solvent induced trypsin denaturation: the role of hydrophobicity0 aComparison of polymer induced and solvent induced trypsin denatu  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcAPR  a201-2050 v1163 a<p>Trypsin adsorption from aqueous buffer by various copolymers of allyl glycidyl ether-ethylene glycol dimethacrylate (AGE-EGDM) copolymer with varying crosslink density increases with increasing crosslink density and the effect slowly wears off after reaching a plateau at 50% crosslink density. The copolymer with 25% crosslink density was reacted with different amines with alkyl/aryl side chains to obtain a series of copolymers with 1,2-amino alcohol functional groups and varying hydrophobicity. Trypsin binding capacity again increases with hydrophobicity of the reacting amine and a good correlation between logP(octanol) of the amine and protein binding is observed. The bound trypsin is denatured to the extent of 90% in spite of the presence of hydrophilic hydroxyl and amino groups. The behavior was comparable to that in mixtures of aqueous buffer and water-miscible organic co-solvents where the solvent concentration required to deactivate 50% of the enzyme (C-50) is dependent on logP(octanol) of the co-solvent. (C) 2014 Elsevier B.V. All rights reserved.</p>10aAdsorption10aDenaturation10aHydrophobicity10aPolymer10aTrypsin1 aJasti, Lakshmi, Swarnalath1 aFadnavis, Nitin, W.1 aAddepally, Uma1 aDaniels, Siona1 aDeokar, Sarika, Babasaheb1 aPonrathnam, Surendra  uhttps://library.ncl.res.in/content/comparison-polymer-induced-and-solvent-induced-trypsin-denaturation-role-hydrophobicity-002358nas a2200301   4500008004100000022001400041245018500055210006900240260006700309300001200376490000700388520119500395653002501590653002501615653003501640653001901675653001201694100003101706700002401737700002901761700002001790700002401810700001901834700001901853700002501872700003001897856012901927       2014                        eng d  a8756-793800aProtein-coated polymer as a matrix for enzyme immobilization: immobilization of trypsin on bovine serum albumin-coated allyl glycidyl ether-ethylene glycol dimethacrylate copolymer0 aProteincoated polymer as a matrix for enzyme immobilization immo  a111 RIVER ST, HOBOKEN 07030-5774, NJ USAbWILEY-BLACKWELLcMAR  a317-3230 v303 a<p>Allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymer with 25% crosslink density (AGE-25) shows excellent bovine serum albumin (BSA) adsorption (up to 16% (w/w)) at pH 8.0 and the adsorbed BSA is strongly bound. This protein-coated polymer provides a novel matrix with naturally existing functional groups such as thiol, amino, and carboxylic acid that are available for covalent immobilization of functional enzymes. Employing appropriate strategies, trypsin as a model protein was covalently bound to BSA-coated matrix both independently, and in a stepwise manner on the same matrix, with less than 5% loss of enzyme activity during immobilization. Glutaraldehyde crosslinking after immobilization provide stable enzyme preparation with activity of 510 units/g recycled up to six times without loss of enzyme activity. AFM studies reveal that the polymer surface has protein peaks and valleys rather than a uniform monolayer distribution of the protein and the immobilized enzyme preparation can best be described as polymer supported cross-linked enzyme aggregates (CLEAs). (c) 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:317-323, 2014</p>10aallyl glycidyl ether10aBovine serum albumin10aethylene glycol dimethacrylate10aImmobilization10aTrypsin1 aJasti, Lakshmi, Swarnalath1 aDola, Sandhya, Rani1 aKumaraguru, Thenkrishnan1 aBajja, Sreedhar1 aFadnavis, Nitin, W.1 aAddepally, Uma1 aRajdeo, Kishor1 aPonrathnam, Surendra1 aDeokar, Sarika, Babasaheb  uhttps://library.ncl.res.in/content/protein-coated-polymer-matrix-enzyme-immobilization-immobilization-trypsin-bovine-serum-001635nas a2200265   4500008004100000022001400041245010100055210006900156260007300225300001000298490000800308520069500316653001401011653001301025653002501038653001501063653001401078653002201092100002901114700002701143700002401170700001901194700002401213856013201237       2014                        eng d  a0926-860X00aRegioselective acylation of 2-methoxy naphthalene catalyzed by supported 12-phosphotungstic acid0 aRegioselective acylation of 2methoxy naphthalene catalyzed by su  aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcSEP  a55-610 v4863 a<p>12-Phosphotungstic acid supported on silica gel, zirconium sulfate, and a combination of silica gel and zirconium sulfate (50% w/w) were employed as solid acid catalysts for regioselective acylation of 2-methoxynaphtalene with acetic anhydride. 1-(6-Methoxynaphthalen-2-yl)ethanone (2,6-AMN), a commercially important intermediate for production of Naproxen, was obtained with excellent selectivity (&gt;98%) at 67-68% conversion using 12-phosphotungstic acid supported on silica gel 20% (w/w) in refluxing tetrachloroethane. The unreacted starting material can be easily separated from the product by a simple crystallization from nonane. (C) 2014 Elsevier B.V. All rights reserved.</p>10aAcylation10aNaproxen10aPhosphotungstic acid10aSilica gel10aSupported10aZirconium sulfate1 aKumaraguru, Thenkrishnan1 aDevi, Ayala, Vedamayee1 aSiddaiah, Vidavalur1 aRajdeo, Kishor1 aFadnavis, Nitin, W.  uhttps://library.ncl.res.in/content/regioselective-acylation-2-methoxy-naphthalene-catalyzed-supported-12-phosphotungstic-acid-002180nas a2200253   4500008004100000022001400041245009300055210006900148260009500217300001000312490000700322520129400329653001601623653002101639653001901660653001401679653002201693653001201715100001901727700002301746700001801769700002401787856011501811       2016                        eng d  a0960-308500aImmobilization of pectinase on reusable polymer support for clarification of apple juice0 aImmobilization of pectinase on reusable polymer support for clar  a165-189 RAILWAY TERRACE, DAVIS BLDG, RUGBY CV21 3HQ, ENGLANDbINST CHEMICAL ENGINEERScJUL  a12-190 v993 a<p>Pectinase (E.C.3.2.1.15) was successfully immobilized on recyclable polymer matrix. The immobilization matrix was prepared by reaction of polyethyleneimine (mol. wt. 70,000) with epoxy-activated acrylate copolymer DILBEAD-VWR. The enzyme pectinase was first adsorbed on the polymer at pH 7.0 via ion exchange and then stabilized by crosslinking with dextran aldehyde. While the free enzyme shows a pH-optimum of 5.0, the immobilized enzyme exhibited high level of activity in a broad pH range of pH 3.0-7.0. Although the thermal stability of free and immobilized enzymes was similar, at room temperature, the immobilized enzyme could be recycled more than 10 times with loss of less than 5% of its activity during clarification of apple juice. On the eventual loss of enzyme activity, the immobilized enzyme and dextran aldehyde can be easily removed from the polymer by a simple treatment with 1N HCl and the polymer can be reused for immobilization of a fresh batch of enzyme. This support also can be reused several times, making the process economically attractive. The properties of apple juice treated with immobilized enzyme were similar to those of that treated with free pectinase. (C) 2016 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.</p>10aApple juice10aDextran aldehyde10aImmobilization10aPectinase10aPolyethyleneimine10aPolymer1 aRajdeo, Kishor1 aHarini, Tirunagari1 aLavanya, Kuna1 aFadnavis, Nitin, W.  uhttps://library.ncl.res.in/content/immobilization-pectinase-reusable-polymer-support-clarification-apple-juice