Hydrolysis of organophosphate insecticides by an immobilized-enzyme system

1979 ◽  
Vol 21 (12) ◽  
pp. 2247-2261 ◽  
Author(s):  
D. M. Munnecke
Keyword(s):  
Immobilized Enzyme ◽  
Enzyme System ◽  
Organophosphate Insecticides ◽  
Hydrolysis Of

On the Preparation of Bovine α-Thrombin

1978 ◽  
Vol 39 (01) ◽  
pp. 193-200 ◽  
Author(s):  
Erwin F Workman ◽  
Roger L Lundblad
Keyword(s):  
Immobilized Enzyme ◽  
Catalytic Properties ◽  
Specific Activity ◽  
Guanidine Hydrochloride ◽  
Low Molecular Weight ◽  
Reversible Process ◽  
Gel Beads ◽  
Tissue Thromboplastin ◽  
C 50 ◽  
Hydrolysis Of

SummaryAn improved method for the preparation of bovine α-thrombin is described. The procedure involves the activation of partially purified prothrombin with tissue thromboplastin followed by chromatography on Sulfopropyl-Sephadex C-50. The purified enzyme is homogeneous on polyacrylamide discontinuous gel electrophoresis and has a specific activity toward fibrinogen of 2,200–2,700 N.I.H. U/mg. Its stability on storage in liquid media is dependent on both ionic strenght and temperature. Increasing ionic strength and decreasing temperature result in optimal stability. The denaturation of α-thrombin by guanidine hydrochloride was found to be a partially reversible process with the renatured species possessing properties similar to “aged” thrombin. In addition, the catalytic properties of a-thrombin covalently attached to agarose gel beads were also examined. The activity of the immobilized enzyme toward fibrinogen was affected to a much greater extent than was the hydrolysis of low molecular weight, synthetic substrates.

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.

Enzyme system of Clostridium stercorarium for hydrolysis of arabinoxylan: reconstitution of the in vivo system from recombinant enzymes

Microbiology ◽  
2004 ◽  
Vol 150 (7) ◽  
pp. 2257-2266 ◽  
Author(s):  
Helmuth Adelsberger ◽  
Christian Hertel ◽  
Erich Glawischnig ◽  
Vladimir V. Zverlov ◽  
Wolfgang H. Schwarz
Keyword(s):  
Extracellular Enzymes ◽  
Enzyme System ◽  
Thermophilic Bacterium ◽  
Recombinant Enzymes ◽  
Type Mode ◽  
Complete Set ◽  
First Time ◽  
Hydrolysis Of

Four extracellular enzymes of the thermophilic bacterium Clostridium stercorarium are involved in the depolymerization of de-esterified arabinoxylan: Xyn11A, Xyn10C, Bxl3B, and Arf51B. They were identified in a collection of eight clones producing enzymes hydrolysing xylan (xynA, xynB, xynC), β-xyloside (bxlA, bxlB, bglZ) and α-arabinofuranoside (arfA, arfB). The modular enzymes Xyn11A and Xyn10C represent the major xylanases in the culture supernatant of C. stercorarium. Both hydrolyse arabinoxylan in an endo-type mode, but differ in the pattern of the oligosaccharides produced. Of the glycosidases, Bxl3B degrades xylobiose and xylooligosaccharides to xylose, and Arf51B is able to release arabinose residues from de-esterified arabinoxylan and from the oligosaccharides generated. The other glycosidases either did not attack or only marginally attacked these oligosaccharides. Significantly more xylanase and xylosidase activity was produced during growth on xylose and xylan. This is believed to be the first time that, in a single thermophilic micro-organism, the complete set of enzymes (as well as the respective genes) to completely hydrolyse de-esterified arabinoxylan to its monomeric sugar constituents, xylose and arabinose, has been identified and the enzymes produced in vivo. The active enzyme system was reconstituted in vitro from recombinant enzymes.

scholarly journals Optimization of a minimal synergistic enzyme system for hydrolysis of raw cassava pulp

RSC Advances ◽  
2017 ◽  
Vol 7 (76) ◽  
pp. 48444-48453 ◽  
Author(s):  
Benjarat Bunterngsook ◽  
Thanaporn Laothanachareon ◽  
Suda Natrchalayuth ◽  
Sirithorn Lertphanich ◽  
Tatsuya Fujii ◽  
...  
Keyword(s):  
Cell Wall ◽  
Enzyme System ◽  
Starch Granules ◽  
Cell Wall Polysaccharides ◽  
Cassava Pulp ◽  
Lignocellulosic Wastes ◽  
Hydrolysis Of

Cassava pulp is an underused agricultural by-product comprising residual starch granules entrapped in cell wall polysaccharides, making it unique from other lignocellulosic wastes in terms of enzymatic processing.

β-Glucosidase: microbial production and effect on enzymatic hydrolysis of cellulose

1977 ◽  
Vol 23 (2) ◽  
pp. 139-147 ◽  
Author(s):  
D. Sternberg ◽  
P. Vuayakumar ◽  
E. T. Reese
Keyword(s):  
Enzymatic Hydrolysis ◽  
Liquid Culture ◽  
Enzyme System ◽  
Microbial Production ◽  
Enzymatic Conversion ◽  
Enzymatic Hydrolysis Of Cellulose ◽  
Black Aspergilli ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of ◽  
Predominant Product

The enzymatic conversion of cellulose is catalyzed by a multiple enzyme system. The Trichoderma enzyme system has been studied extensively and has insufficient β-glucosidase (EC 3.2.1.21) activity for the practical saccharification of cellulose. The black aspergilli (A. niger and A. phoenicis) were superior producers of β-glucosidase and a method for production of this enzyme in liquid culture is presented. When Trichoderma cellulase preparations are supplemented with β-glucosidase from Aspergillus during practical saccharifications, glucose is the predominant product and the rate of saccharification is significantly increased. The stimulatory effect of β-glucosidase appears to be due to the removal of inhibitory levels of cellobiose.

Modeling and Optimization of Lipase-Catalyzed Partial Hydrolysis for Diacylglycerol Production in Packed Bed Reactor

2016 ◽  
Vol 12 (7) ◽  
pp. 681-689 ◽  
Author(s):  
Eng-Tong Phuah ◽  
Yee-Ying Lee ◽  
Teck-Kim Tang ◽  
Oi-Ming Lai ◽  
Thomas Shean-Yaw Choong ◽  
...  
Keyword(s):  
Immobilized Enzyme ◽  
Rhizomucor Miehei ◽  
Packed Bed ◽  
Packed Bed Reactor ◽  
Partial Hydrolysis ◽  
Optimal Conditions ◽  
Lack Of Fit ◽  
Bed Height ◽  
Hydrolysis Of ◽  
Quadratic Models

Abstract Response surface methodology (RSM) was employed to optimize the process variables namely packed bed height (cm) and flow rates (ml/min) on diacylglycerol (DAG) production via partial hydrolysis of palm oil using immobilized Rhizomucor miehei lipase in packed bed reactor (PBR). Quadratic models were successfully developed for both DAG(y) and unhydrolyzed triacylglycerol ((un)TAG) with determination coefficient (R2) of 0.9931 and 0.9986, respectively coupled with insignificant lack of fit (p > 0.05). Optimal conditions for DAG synthesis were evaluated to be 10 cm packed bed height and 3.8 ml/min flow rate. Immobilized enzyme can be reused up to 10 times without significant changes in enzymatic activity. The partial hydrolysis under studied was found to be mass transfer-controlled.

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