THE SAP OF THE BIRCH TREE, BETULA PAPYRIFERA MARSH.: I. THE AMYLASE SYSTEM

1942 ◽  
Vol 20b (6) ◽  
pp. 114-120 ◽  
Author(s):  
E. Bois ◽  
W. O. Chubb
Keyword(s):  
Cellulose Acetate ◽  
Betula Papyrifera ◽  
Optimum Conditions ◽  
Maximum Production ◽  
Birch Tree ◽  
Optimum Ph ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

The amylase system of birch sap consists of a cellobiogenic amylase and most probably a glucogenic amylase. The optimum conditions of pH and temperature are pH 5. 5 at 4 °C. to 6.3 at 60 °C. The maximum production of cellobiose occurred at a temperature of 50 °C. at the optimum pH for this temperature. The optimum conditions for the production of glucose were pH 5.5 and a temperature of 50 °C.It is felt that these new facts throw some additional light on the constitution of starch, and that possibly birch sap might serve as a source of cellobiose, which has heretofore only been prepared commercially by hydrolysis of cellulose acetate.

HYDROLYSIS OF CELLULOSE ACETATE SULPHATE IN ACETONE

1954 ◽  
Vol 32 (9) ◽  
pp. 815-822 ◽  
Author(s):  
Karl Keirstead ◽  
John Myers
Keyword(s):  
Acetic Acid ◽  
Cellulose Acetate ◽  
Sulphuric Acid ◽  
Potentiometric Titration ◽  
Titration Method ◽  
Acetate Ester ◽  
Hydrolysis Of Cellulose ◽  
Potentiometric Titration Method ◽  
Hydrolysis Of

When cellulose acetate sulphate is dissolved in acetone the hydrolysis of the sulphate ester is rapid compared with that of the acetate ester. In 70% acetone the relative rates are reversed. Hydrolysis of the sulphate ester in acetone is greatly affected by the temperature. At 25 °C. or greater the hydrolysis is complete after 24 hr. A potentiometric titration method has been developed for the estimation of sulphuric acid in the presence of smaller amounts of acetic acid.

scholarly journals Production of Recombinant Trichoderma reesei Cellobiohydrolase II in a New Expression System Based on Wickerhamomyces anomalus

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Dennis J. Díaz-Rincón ◽  
Ivonne Duque ◽  
Erika Osorio ◽  
Alexander Rodríguez-López ◽  
Angela Espejo-Mojica ◽  
...  
Keyword(s):  
Trichoderma Reesei ◽  
Recombinant Expression ◽  
Expression System ◽  
Enzymatic Extract ◽  
Native Strain ◽  
Wickerhamomyces Anomalus ◽  
Optimum Ph ◽  
Hydrolysis Of Cellulose ◽  
Cellobiohydrolase Ii ◽  
Hydrolysis Of

Cellulase is a family of at least three groups of enzymes that participate in the sequential hydrolysis of cellulose. Recombinant expression of cellulases might allow reducing their production times and increasing the low proteins concentrations obtained with filamentous fungi. In this study, we describe the production of Trichoderma reesei cellobiohydrolase II (CBHII) in a native strain of Wickerhamomyces anomalus. Recombinant CBHII was expressed in W. anomalus 54-A reaching enzyme activity values of up to 14.5 U L−1. The enzyme extract showed optimum pH and temperature of 5.0–6.0 and 40°C, respectively. Enzyme kinetic parameters (KM of 2.73 mM and Vmax of 23.1 µM min−1) were between the ranges of values reported for other CBHII enzymes. Finally, the results showed that an enzymatic extract of W. anomalus 54-A carrying the recombinant T. reesei CBHII allows production of reducing sugars similar to that of a crude extract from cellulolytic fungi. These results show the first report on the use of W. anomalus as a host to produce recombinant proteins. In addition, recombinant T. reesei CBHII enzyme could potentially be used in the degradation of lignocellulosic residues to produce bioethanol, based on its pH and temperature activity profile.

Kinetic study of the hydrolysis of cellulose acetate in the pH range of 2–10

1966 ◽  
Vol 10 (5) ◽  
pp. 825-832 ◽  
Author(s):  
Kenneth D. Vos ◽  
Floyd O. Burris ◽  
Robert L. Riley
Keyword(s):  
Kinetic Study ◽  
Cellulose Acetate ◽  
Hydrolysis Of Cellulose ◽  
Ph Range ◽  
Hydrolysis Of

scholarly journals Hydrolysis of Cellulose from Oil Palm Empty Fruit Bunch using Aspergillus niger

2021 ◽  
Vol 226 ◽  
pp. 00042
Author(s):  
Sri Sugiwati ◽  
Suaidah Suaidah ◽  
Eka Triwahyuni ◽  
Muryanto Muryanto ◽  
Yosie Andriani ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Oil Palm ◽  
Hydrolytic Activity ◽  
Reducing Sugar ◽  
Empty Fruit Bunch ◽  
Hydrolysis Time ◽  
Glucose Assay ◽  
Optimum Ph ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

Oil palm empty fruit bunch (OPEFB) constitutes a great source of lignocellulosic biomass, mainly comprising of 66.97 % of holocellulose (cellulose and hemicellulose) and 24.45 % of lignin. This present work aimed to hydrolyze cellulose present in OPEFB to form glucose with the aid of Aspergillus niger. A. niger is a type of filamentous fungi able to produce cellulase, a multi-enzyme complex consisting of an endoglucanase, exoglucanase, and β-glucosidase, able to converting cellulose into glucose. The glucose produced is then fermented to produce bioethanol. The present study compared hydrolytic activity of cellulose between OPEFB with pretreatment using NaOH 10 % and OPEFB without pretreatment, concerning temperature, pH, and hydrolysis time. The concentration of reducing sugar derived from cellulosic hydrolysis was determined by using a glucose assay of 3.5-dinitrosalicylic acid. The results showed that the optimum temperature for hydrolysis of cellulose OPEFB (pretreated and untreated) was at 40 °C and the optimum pH was 5.0 for OPEFB-untreated and 5.5 for OPEFB-pretreated. Hydrolysis of cellulose at 40 °C and 3 d yielded reducing sugar 13.01 mg mL−1 and 1.16 mg mL−1 for OPEFB-untreated and OPEFB-pretreated, respectively.

Re-esterification during the Hydrolysis of Cellulose Acetate

1952 ◽  
Vol 74 (16) ◽  
pp. 4105-4107 ◽  
Author(s):  
Carl J. Malm ◽  
Leo J. Tanghe ◽  
Barbara C. Laird ◽  
Glenn D. Smith
Keyword(s):  
Cellulose Acetate ◽  
Hydrolysis Of Cellulose ◽  
Hydrolysis Of

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.

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