Aktivitas Immobilized α-Amylase dan Free α-Amylase dari Zoogloea ramigera ABL 1 dalam Medium Pati Cair dengan Perlakuan Faktor Lingkungan

2011 ◽  
Vol 16 (1) ◽  
Author(s):  
Endah Retnaningrum ◽  
Zukrotun Nafisah
Keyword(s):  
Free Enzyme ◽  
Zoogloea Ramigera

Penelitian ini bertujuan mengetahui karakter aktivitas immobilized amylase dan free amylase dari isolat amilolitik Zoogloea ramigera ABL 1 dengan beberapa kondisi lingkungan yang berbeda, seperti suhu, pH, temperatur, dan ion logam. Amilase dengan aktivitas enzimatik tertinggi diunduh dari kultur bakteri dalam medium pati cair melalui sentrifugasi. Enzim hasil pengunduhan kemudian diperlakukan immobilization technique dengan direaksikan Ca-alginat. Enzim tanpa perlakuan immobilization technique merupakan free amylase. Kedua amilase kemudian dikarakterisasi berdasar aktivitas spesifik enzim pada kondisi temperatur 30°C; pH (4−10), pH 7; temperature (10−80°C), dan penambahan 1 mM ion logam (CaCl2, CuSO4, FeSO4.7H2O, MgSO4.7H2O, MnCl2..4H2O, ZnSO4) dengan temperatur dan suhu optimum hasil penelitian sebelumnya. Aktivitas spesifik immobilized amylase pada semua kondisi lingkungan lebih stabil dan tinggi daripada free amylase. Immobilized amylase bersifat stabil pada kisaran suhu 10–60°C, dan aktivitas optimumnya terjadi pada suhu 30°C. Immobilized amylase tersebut juga stabil pada kisaran pH 4–7, dengan aktivitas optimum berada pada pH 7. Aktivitas immobilized amylase yang tertinggi terjadi pada penambahan 1 mM ion logam MnCl2.4H2O. Sebaliknya, free enzyme dipengaruhi oleh penambahan 1 mM CaCl2. Perlakuan immobilization technique pada amilase dari Zoogloea ramigera ABL 1 terbukti dapat digunakan untuk meningkatkan aktivitas spesifik enzim dengan kisaran pH dan temperatur yang luas, serta penambahan ion logam.

Immobilized Nanoparticles-Mediated Enzymatic Hydrolysis of Cellulose for Clean Sugar Production: A Novel Approach

2019 ◽  
Vol 15 (3) ◽  
pp. 296-303 ◽  
Author(s):  
Swapnil Gaikwad ◽  
Avinash P. Ingle ◽  
Silvio Silverio da Silva ◽  
Mahendra Rai
Keyword(s):  
Catalytic Activity ◽  
Enzymatic Hydrolysis ◽  
Immobilized Enzyme ◽  
Free Enzyme ◽  
Magnetic Nanomaterials ◽  
Sugar Production ◽  
Cellulase Enzyme ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

Background: Enzymatic hydrolysis of cellulose is an expensive approach due to the high cost of an enzyme involved in the process. The goal of the current study was to apply magnetic nanomaterials as a support for immobilization of enzyme, which helps in the repeated use of immobilized enzyme for hydrolysis to make the process cost-effective. In addition, it will also provide stability to enzyme and increase its catalytic activity. Objective: The main aim of the present study is to immobilize cellulase enzyme on Magnetic Nanoparticles (MNPs) in order to enable the enzyme to be re-used for clean sugar production from cellulose. Methods: MNPs were synthesized using chemical precipitation methods and characterized by different techniques. Further, cellulase enzyme was immobilized on MNPs and efficacy of free and immobilized cellulase for hydrolysis of cellulose was evaluated. Results: Enzymatic hydrolysis of cellulose by immobilized enzyme showed enhanced catalytic activity after 48 hours compared to free enzyme. In first cycle of hydrolysis, immobilized enzyme hydrolyzed the cellulose and produced 19.5 ± 0.15 gm/L of glucose after 48 hours. On the contrary, free enzyme produced only 13.7 ± 0.25 gm/L of glucose in 48 hours. Immobilized enzyme maintained its stability and produced 6.15 ± 0.15 and 3.03 ± 0.25 gm/L of glucose in second and third cycle, respectively after 48 hours. Conclusion: This study will be very useful for sugar production because of enzyme binding efficiency and admirable reusability of immobilized enzyme, which leads to the significant increase in production of sugar from cellulosic materials.

scholarly journals Drug-Free Enzyme-Based Bactericidal Nanomotors against Pathogenic Bacteria

2021 ◽  
Author(s):  
Diana Vilela ◽  
Nuria Blanco-Cabra ◽  
Ander Eguskiza ◽  
Ana C. Hortelao ◽  
Eduard Torrents ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Free Enzyme ◽  
Drug Free

scholarly journals Catalysis by Candida antarctica B (CALB) immobilized on natural pure silica by adsorption: comparison with the free enzyme

2017 ◽  
Vol 107 (1) ◽  
pp. 10418
Author(s):  
A.J. Djossou ◽  
M Mazou ◽  
A.C. Toukourou ◽  
F.P. Tchobo ◽  
J Blin ◽  
...  
Keyword(s):  
Candida Antarctica ◽  
Free Enzyme ◽  
Pure Silica

scholarly journals FACTORS AFFECTING THE YIELD OF SPECIFIC ENZYME IN CULTURES OF THE BACILLUS DECOMPOSING THE CAPSULAR POLYSACCHARIDE OF TYPE III PNEUMOCOCCUS

1932 ◽  
Vol 55 (3) ◽  
pp. 377-391 ◽  
Author(s):  
René Dubos
Keyword(s):  
Capsular Polysaccharide ◽  
Free Enzyme ◽  
Appreciable Amount ◽  
Specific Substrate ◽  
Specific Enzyme ◽  
Factors Affecting ◽  
Type Iii ◽  
Cultural Conditions ◽  
Bacterial Enzyme ◽  
Specific Substance

All improved method is described for the preparation, concentration, and purification of a bacterial enzyme capable of decomposing the capsular polysaccharide of Type III Pneumococcus. The cultural conditions for the growth of the specific microorganism must be such that the capsular polysaccharide is completely decomposed before any appreciable amount of free enzyme is released into the medium. This reduces to a minimum the decomposition of the specific substrate by the free enzyme. As a result, a larger part of the specific substance remains as a source of energy for the growing microorganism and less enzyme is lost through inactivation during the course of decomposition of the specific substrate. A marked stimulation of growth and of enzyme production occurs when small amounts of yeast extract are added to the medium and when the cultures are incubated under conditions of increased aeration. Special emphasis is placed upon the fact that, thus far, appreciable amounts of the specific enzyme have been obtained only when the capsular polysaccharide itself, or the aldobionic acid derived from it, was present in the culture medium.

scholarly journals The apparent Km is a misleading kinetic indicator

1986 ◽  
Vol 239 (1) ◽  
pp. 175-178 ◽  
Author(s):  
I W Plesner
Keyword(s):  
Substrate Concentration ◽  
Kinetic Data ◽  
Substrate Binding ◽  
Enzymic Activity ◽  
Free Enzyme ◽  
Ligand Concentration ◽  
Double Reciprocal Plot ◽  
Michaelis Constant ◽  
Formal Framework ◽  
Enzyme Species

When information concerning whether or not a ligand interacts with the same enzyme species as do the substrates, the variation of the Michaelis constant Km (for each substrate) with ligand concentration is sometimes used as a diagnostic. It is shown that the Michaelis constant is of no particular value in this respect and may be misleading. Thus, depending on the mechanism, Km may vary with ligand concentration even though the ligand interacts with species far removed in the mechanism from the substrate-binding steps, and it may stay constant in cases where the ligand competes directly for the free enzyme. In contrast, the slope of a double-reciprocal plot of the kinetic data (= Km/Vmax.) (or, equivalently, the ordinate intercept of a Hanes plot A/v versus A, where A is the substrate concentration) independently of the particular mechanism involved uniquely signifies whether or not such interaction occurs. The results clearly indicate that, for purposes other than communicating the substrate concentration yielding control of the enzymic activity, usage of Km and its variation with ligand concentration should be avoided and interest instead focused on the slope, in accordance with the long-established rules of Cleland [Biochim. Biophys. Acta (1963) 67, 188-196], for which the present analysis provides the formal framework.

Tools and strategies for constructing cell-free enzyme pathways

2019 ◽  
Vol 37 (1) ◽  
pp. 91-108 ◽  
Author(s):  
Kerstin Petroll ◽  
Dominik Kopp ◽  
Andrew Care ◽  
Peter L. Bergquist ◽  
Anwar Sunna
Keyword(s):  
Free Enzyme

scholarly journals Novas bactérias diazotróficas endofíticas na cultura do trigo em interação com a adubação nitrogenada, no campo

2008 ◽  
Vol 32 (3) ◽  
pp. 1099-1106 ◽  
Author(s):  
Valeria Marino Rodrigues Sala ◽  
Elke Jurandy Bran Nogueira Cardoso ◽  
Jose Guilherme de Freitas ◽  
Adriana Parada Dias da Silveira
Keyword(s):  
Triticum Aestivum ◽  
Triticum Durum ◽  
Zoogloea Ramigera

Bactérias diazotróficas pertencentes a diferentes espécies podem estar associadas a gramíneas, como o trigo, promovendo incrementos no crescimento e na produtividade de grãos. Foi realizado um experimento, em condições de campo, com o objetivo de avaliar os benefícios e a viabilidade econômica da inoculação de novos isolados homólogos de bactérias diazotróficas endofíticas em genótipos de trigo sob diferentes doses de N. Foram empregados três isolados de bactérias diazotróficas endofíticas (IAC-AT-8-Azospirillum brasiliense, IAC-HT-11-Achromobacter insolitus e IAC-HT-12-Zoogloea ramigera), dois genótipos de trigo (ITD- 19-Triticum durum L. e IAC-370-Triticum aestivum hard L.) e três doses de N (0, 60 e 120 kg ha-1). Foram avaliados, no estádio de perfilhamento e de maturidade fisiológica, a matéria seca, o N acumulado e o índice de eficiência de utilização do N na parte aérea e na colheita; a produtividade de grãos, os componentes de rendimento e os índices de colheita para biomassa e N. No estádio de perfilhamento, somente houve aumento na produção de biomassa com a inoculação de Azospirillum brasiliense e Achromobacter insolitus no genótipo IAC-370, com a adição de N. Entretanto, não houve especificidade dos genótipos de trigo empregados e essas novas bactérias diazotróficas endofíticas para as demais caracaterísticas avaliadas. Houve aumento no acumulado de N na espiga com a inoculação de Azospirillum brasiliense. A inoculação de Achromobacter insolitus propiciou aumento da produtividade de grãos, na maior dose de N utilizada (120 kg ha-1). A inoculação, embora não tenha substituído a adubação nitrogenada, reverteu-se em lucro para o agricultor.

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