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Immobilization of enzymes is one of the most promising methods in enzyme performance enhancement,... more Immobilization of enzymes is one of the most promising methods in enzyme performance enhancement, including stability, recovery, and reusability. However, investigation of suitable solid support in enzyme immobilization is still a scientific challenge. Polyethersulfone (PES) and aminated PES (PES-NH 2 ) were successfully synthesized as novel materials for immobilization. Membranes with various pore sizes (from 10-600 nm) based on synthesized PES and PES-NH 2 polymers were successfully fabricated to be applied as bioreactors to increase the immobilized lipase performances. The influence of pore sizes, concentration of additives, and the functional groups that are attached on the PES backbone on enzyme loading and enzyme activity was studied. The largest enzyme loading was obtained by Mucor miehei lipase immobilized onto a PES-NH 2 membrane composed of 10% of PES-NH 2 , 8% of dibutyl phthalate (DBP), and 5% of polyethylene glycol (PEG) (872.62 µg/cm 2 ). Hydrolytic activity of the immobilized lipases indicated that the activities of biocatalysts are not significantly decreased by immobilization. From the reusability test, the lipase immobilized onto PES-NH 2 showed a better constancy than the lipase immobilized onto PES (the percent recovery of the activity of the lipases immobilized onto PES-NH 2 and PES are 97.16% and 95.37%, respectively), which indicates that this novel material has the potential to be developed as a bioreactor for enzymatic reactions.
ABSTRAK:< br/>< br/> Kerugian yang diakibatkan oleh k... more ABSTRAK:< br/>< br/> Kerugian yang diakibatkan oleh korosi membuat para ahli mengembangkan pembuatan inhibitor korosi berbahan dasar senyawa organik. Salah satu senyawa yang dapat digunakan adalah prolin, karena memiliki gugus asam karboksilat ...
Jurnal Kimia Indonesia, Jan 1, 2010
icmns.fa.itb.ac.id
Enzymes are potential catalysts in biodiesel manufacturing because of their good properties (good... more Enzymes are potential catalysts in biodiesel manufacturing because of their good properties (good performance in regioselectivity, stereoselectivity, biodegradable, etc.). However, it has many limitations such as zero reusability indication, unstable toward high temperature, organic solutions, acids, bases, and mechanical influences. One of the ways to handle these problems is to immobilize enzymes onto the suitable solid supports. Polyether sulfone (PES) has good resistant properties towards chemicals, thermals, and mechanics. PES interaction with the enzyme such as lipase could be occured by hydrophilic interaction. PES modification is one of the ways to form covalent bonds with the enzyme in order to prevent the leaching out of lipase from the solid support. Aminated PES was synthesized through three main parts; which are the synthesis of PES, the nitration of PES, and the reduction of PES-NO2. The synthesized PES-NH2 is brown powder having the infrared characteristic peaks at wave numbers of 1320.1, 1187.1, 1236.5, and double bands at 3077.4 cm -1 . Based on the NMR spectrums analysis, PES-NH2 was successfully formed from the synthesized PES produced by the Dean Stark trap and Microwave Assisted Organic Synthesis (MAOS) methods. Aminated PES is applicable as solid support of lipase to carry out transesterification reaction of triglyceride to improve biodiesel production.
Sains Malaysiana, Jan 1, 2011
In spite of their excellent catalytic properties, enzymes should be improved before their impleme... more In spite of their excellent catalytic properties, enzymes should be improved before their implementation both in industrial and laboratorium scales. Immobilization of enzyme is one of the ways to improve their properties. Candida antarctica lipase B (Cal-B) has been reported in numerous publications to be a particularly useful enzyme catalizing in many type of reaction including regio-and enantio-synthesis. For this case, cross-linking of immobilized 2,7,8 diepoxy octane is one of methods that proved significantly more stable from denaturation by heat, organic solvents, and proteolysis than lyophilized powder or soluble enzymes. More over, the aim of this procedure is to improve the activity and reusability of lipase. Enzyme kinetics test was carried out by transesterification reaction between 4-nitrophenyl acetate (pNPA) and methanol by varying substrate concentrations, and the result is immobilized enzymes follows the Michaelis-Menten models and their activity is match with previous experiment. Based on the V max values, the immobilized enzymes showed higher activity than the free enzyme. Cross-linking of immobilized lipase indicate that cross-linking by lower concentration of cross-linker, FIC (immobilized lipase that was incubated for 24 h) gave the highest activity and cross-linking by higher concentration of cross-linker, PIC (immobilized lipase that was incubated for 2 h) gives the highest activity. However, pore size and saturation level influenced their activity. ABSTRAK Walaupun sifat katalitisis yang sangat baik, enzim perlu ditingkatkan keupayaannya sebelum diimplementasikan dalam skala industri maupun makmal. Imobilisasi enzim merupakan salah satu cara untuk memperbaiki sifat enzim. Candida antarctica lipase B (Cal-B) telah dilaporkan dalam sejumlah penerbitan sebagai enzim yang dapat digunakan dalam mengkatalisis enzim dalam berbagai tindak balas termasuk sintesis yang bersifat regio-dan enantio-selektif. Dalam kajian ini didapati taut-silang dalam Cal-B terimobilisasi oleh 1,2,7,8 diepoksi oktana merupakan salah satu kaedah yang terbukti secara signifikan lebih stabil terhadap penyahaslian oleh pemanasan, pelarut organik, dan proteolisis dibandingkan dengan enzim dalam bentuk larutan maupun serbuk terliofilik. Selain itu, tujuan kajian ini adalah meningkatkan keaktifan dan kebolehulangan pemakaian lipase. Ujian kinetik enzim dilakukan melalui tindak balas transesterifikasi antara 4-nitrofenil asetat (pNPA) dan metanol dengan memvariasikan kepekatan substrat, dan hasilnya adalah bahwa enzim terimobilisasi mengikuti model Michaelis-Menten serta keaktifannya sesuai dengan hasil kajian sebelumnya. Berdasarkan nilai V max , enzim yang terimobilisasi menunjukkan keaktifan yang lebih tinggi daripada enzim bebas. Taut-silang pada lipase yang terimobilisasi menunjukkan bahawa taut-silang oleh adanya rangkaian silang FIC (lipase terimobilisasi yang diinkubasi selama 24 jam) berkepekatan rendah menunjukkan keaktifan tertinggi, sedangkan taut-silang oleh adanya rangkaian silang PIC (lipase terimobilisasi yang diinkubasi selama 2 jam) berkepekatan lebih tinggi menunjukkan keaktifan tertinggi. Di samping itu, saiz liang dan aras ketepuan memberikan pengaruh terhadap keaktfian enzim tersebut. Kata kunci: Candida antarctica lipase B (Cal-B); imobilisasi enzim; taut-silang
In spite of their excellent catalytic properties, enzymes should be improved before their impleme... more In spite of their excellent catalytic properties, enzymes should be improved before their implementation both in industrial and laboratorium scale. Immobilization of enzyme is one of the way that purposed in their properties improvement. Candida antarctica lipase B (Cal-B) has been shown a great number in numerous publications to be a particularly useful enzyme catalizing in many type of reaction including regio-and enantio-synthesis. For this case, cross-linking of immobilized Cal-B with 1,2,7,8 diepoxy octane is one of methods that proved significantly more stable from denaturation by heat, organic solvents, and proteolysis than lyophilized powder or soluble enzymes. More over, the aim of this procedure is improvement of enzymes activity and reusability. Enzyme kinetics test of immobilized enzymes folows the Michaelis-Menten models, and their activity is match with previous experiment. According V max values of immobilized enzymes and free enzyme indicated that immobilized enzymes show higher activity than free enzyme. The cross-linking of immobilized enzyme gives the result that for lower cross-linker concentration, FIC (Full immobilization Crystals)
Immobilization of enzymes is one of the most promising methods in enzyme performance enhancement,... more Immobilization of enzymes is one of the most promising methods in enzyme performance enhancement, including stability, recovery, and reusability. However, investigation of suitable solid support in enzyme immobilization is still a scientific challenge. Polyethersulfone (PES) and aminated PES (PES-NH 2 ) were successfully synthesized as novel materials for immobilization. Membranes with various pore sizes (from 10-600 nm) based on synthesized PES and PES-NH 2 polymers were successfully fabricated to be applied as bioreactors to increase the immobilized lipase performances. The influence of pore sizes, concentration of additives, and the functional groups that are attached on the PES backbone on enzyme loading and enzyme activity was studied. The largest enzyme loading was obtained by Mucor miehei lipase immobilized onto a PES-NH 2 membrane composed of 10% of PES-NH 2 , 8% of dibutyl phthalate (DBP), and 5% of polyethylene glycol (PEG) (872.62 µg/cm 2 ). Hydrolytic activity of the immobilized lipases indicated that the activities of biocatalysts are not significantly decreased by immobilization. From the reusability test, the lipase immobilized onto PES-NH 2 showed a better constancy than the lipase immobilized onto PES (the percent recovery of the activity of the lipases immobilized onto PES-NH 2 and PES are 97.16% and 95.37%, respectively), which indicates that this novel material has the potential to be developed as a bioreactor for enzymatic reactions.
ABSTRAK:< br/>< br/> Kerugian yang diakibatkan oleh k... more ABSTRAK:< br/>< br/> Kerugian yang diakibatkan oleh korosi membuat para ahli mengembangkan pembuatan inhibitor korosi berbahan dasar senyawa organik. Salah satu senyawa yang dapat digunakan adalah prolin, karena memiliki gugus asam karboksilat ...
Jurnal Kimia Indonesia, Jan 1, 2010
icmns.fa.itb.ac.id
Enzymes are potential catalysts in biodiesel manufacturing because of their good properties (good... more Enzymes are potential catalysts in biodiesel manufacturing because of their good properties (good performance in regioselectivity, stereoselectivity, biodegradable, etc.). However, it has many limitations such as zero reusability indication, unstable toward high temperature, organic solutions, acids, bases, and mechanical influences. One of the ways to handle these problems is to immobilize enzymes onto the suitable solid supports. Polyether sulfone (PES) has good resistant properties towards chemicals, thermals, and mechanics. PES interaction with the enzyme such as lipase could be occured by hydrophilic interaction. PES modification is one of the ways to form covalent bonds with the enzyme in order to prevent the leaching out of lipase from the solid support. Aminated PES was synthesized through three main parts; which are the synthesis of PES, the nitration of PES, and the reduction of PES-NO2. The synthesized PES-NH2 is brown powder having the infrared characteristic peaks at wave numbers of 1320.1, 1187.1, 1236.5, and double bands at 3077.4 cm -1 . Based on the NMR spectrums analysis, PES-NH2 was successfully formed from the synthesized PES produced by the Dean Stark trap and Microwave Assisted Organic Synthesis (MAOS) methods. Aminated PES is applicable as solid support of lipase to carry out transesterification reaction of triglyceride to improve biodiesel production.
Sains Malaysiana, Jan 1, 2011
In spite of their excellent catalytic properties, enzymes should be improved before their impleme... more In spite of their excellent catalytic properties, enzymes should be improved before their implementation both in industrial and laboratorium scales. Immobilization of enzyme is one of the ways to improve their properties. Candida antarctica lipase B (Cal-B) has been reported in numerous publications to be a particularly useful enzyme catalizing in many type of reaction including regio-and enantio-synthesis. For this case, cross-linking of immobilized 2,7,8 diepoxy octane is one of methods that proved significantly more stable from denaturation by heat, organic solvents, and proteolysis than lyophilized powder or soluble enzymes. More over, the aim of this procedure is to improve the activity and reusability of lipase. Enzyme kinetics test was carried out by transesterification reaction between 4-nitrophenyl acetate (pNPA) and methanol by varying substrate concentrations, and the result is immobilized enzymes follows the Michaelis-Menten models and their activity is match with previous experiment. Based on the V max values, the immobilized enzymes showed higher activity than the free enzyme. Cross-linking of immobilized lipase indicate that cross-linking by lower concentration of cross-linker, FIC (immobilized lipase that was incubated for 24 h) gave the highest activity and cross-linking by higher concentration of cross-linker, PIC (immobilized lipase that was incubated for 2 h) gives the highest activity. However, pore size and saturation level influenced their activity. ABSTRAK Walaupun sifat katalitisis yang sangat baik, enzim perlu ditingkatkan keupayaannya sebelum diimplementasikan dalam skala industri maupun makmal. Imobilisasi enzim merupakan salah satu cara untuk memperbaiki sifat enzim. Candida antarctica lipase B (Cal-B) telah dilaporkan dalam sejumlah penerbitan sebagai enzim yang dapat digunakan dalam mengkatalisis enzim dalam berbagai tindak balas termasuk sintesis yang bersifat regio-dan enantio-selektif. Dalam kajian ini didapati taut-silang dalam Cal-B terimobilisasi oleh 1,2,7,8 diepoksi oktana merupakan salah satu kaedah yang terbukti secara signifikan lebih stabil terhadap penyahaslian oleh pemanasan, pelarut organik, dan proteolisis dibandingkan dengan enzim dalam bentuk larutan maupun serbuk terliofilik. Selain itu, tujuan kajian ini adalah meningkatkan keaktifan dan kebolehulangan pemakaian lipase. Ujian kinetik enzim dilakukan melalui tindak balas transesterifikasi antara 4-nitrofenil asetat (pNPA) dan metanol dengan memvariasikan kepekatan substrat, dan hasilnya adalah bahwa enzim terimobilisasi mengikuti model Michaelis-Menten serta keaktifannya sesuai dengan hasil kajian sebelumnya. Berdasarkan nilai V max , enzim yang terimobilisasi menunjukkan keaktifan yang lebih tinggi daripada enzim bebas. Taut-silang pada lipase yang terimobilisasi menunjukkan bahawa taut-silang oleh adanya rangkaian silang FIC (lipase terimobilisasi yang diinkubasi selama 24 jam) berkepekatan rendah menunjukkan keaktifan tertinggi, sedangkan taut-silang oleh adanya rangkaian silang PIC (lipase terimobilisasi yang diinkubasi selama 2 jam) berkepekatan lebih tinggi menunjukkan keaktifan tertinggi. Di samping itu, saiz liang dan aras ketepuan memberikan pengaruh terhadap keaktfian enzim tersebut. Kata kunci: Candida antarctica lipase B (Cal-B); imobilisasi enzim; taut-silang
In spite of their excellent catalytic properties, enzymes should be improved before their impleme... more In spite of their excellent catalytic properties, enzymes should be improved before their implementation both in industrial and laboratorium scale. Immobilization of enzyme is one of the way that purposed in their properties improvement. Candida antarctica lipase B (Cal-B) has been shown a great number in numerous publications to be a particularly useful enzyme catalizing in many type of reaction including regio-and enantio-synthesis. For this case, cross-linking of immobilized Cal-B with 1,2,7,8 diepoxy octane is one of methods that proved significantly more stable from denaturation by heat, organic solvents, and proteolysis than lyophilized powder or soluble enzymes. More over, the aim of this procedure is improvement of enzymes activity and reusability. Enzyme kinetics test of immobilized enzymes folows the Michaelis-Menten models, and their activity is match with previous experiment. According V max values of immobilized enzymes and free enzyme indicated that immobilized enzymes show higher activity than free enzyme. The cross-linking of immobilized enzyme gives the result that for lower cross-linker concentration, FIC (Full immobilization Crystals)