The catalytic and kinetic characterization of Bacillus subtilis MK775302 milk clotting enzyme: comparison with calf rennet as a coagulant in white soft cheese manufacture.

Background: Calf rennet is considered the traditional source of milk clotting enzyme (MCE). However, increasing cheese consumption with decreasing the calf rennet supply had encouraged the quest for new rennet alternatives. The purpose of this study is to acquire more information about the catalytic and kinetic properties of partially purified Bacillus subtilis MK775302 MCE and to assess the role of enzyme in cheese manufacture.

Effect of aluminum leaching pretreatment on catalytic pyrolysis of metallised food packaging plastics and its linear and nonlinear kinetic behaviour.

This research aims to study the effect of aluminum (Al) leaching pre-treatment on the catalytic pyrolysis of metallised food packaging plastics waste (MFPW). The experiments started with removal of Al from MFPW using leaching process to prepare Al-free mixed plastic waste (MPW). The catalytic pyrolysis of MPW over ZSM-5 zeolite catalyst was carried out using thermogravimetric (TG) analysis coupled with FTIR, while GC-MS was used to observe the compounds of the volatile products.

Pyrolysis Kinetic Behaviour of Glass Fibre-Reinforced Epoxy Resin Composites Using Linear and Nonlinear Isoconversional Methods.

Due to the increasing demand for glass fibre-reinforced epoxy resin composites (GFRC), huge amounts of GFRC waste are produced annually in different sizes and shapes, which may affect its thermal and chemical decomposition using pyrolysis technology. In this context, this research aims to study the effect of mechanical pre-treatment on the pyrolysis behaviour of GFRC and its pyrolysis kinetic. The experiments were started with the fabrication of GFRC panels using the vacuum-assisted resin transfer method followed by crushing the prepared panels using ball milling, thus preparing the milled GFRC with uniform shape and size.

Pyrolysis kinetic behaviour and TG-FTIR-GC-MS analysis of Coronavirus Face Masks.

In the times of Covid-19, face masks are considered to be the main source of protection against the virus that reduces its spread. These masks are classified as single-use medical products with a very short service life, estimated at few days, hence millions of contaminated masks are generated daily in the form of hazardous materials, what requires to develop a safe method to dispose of them, especially since some of them are loaded with viruses. 3-ply face masks (3PFM) represent the major fraction of this waste and are composed mainly from polypropylene and melt blown filter with high content of volatile substances (96.

Catalytic Pyrolysis Kinetic Behavior and TG-FTIR-GC-MS Analysis of Metallized Food Packaging Plastics with Different Concentrations of ZSM-5 Zeolite Catalyst.

Recently, the pyrolysis process has been adapted as a sustainable strategy to convert metallized food packaging plastics waste (MFPW) into energy products (paraffin wax, biogas, and carbon black particles) and to recover aluminum. Usually, catalysts are used in pyrolysis treatment to refine pyrolysis products and to increase their yield. In order to study the effect of a catalyst on the formulated volatile products, this work aims to study the pyrolysis behavior of MFPW in presence of catalyst, using TG-FTIR-GC-MS system.

Modeling of Metalized Food Packaging Plastics Pyrolysis Kinetics Using an Independent Parallel Reactions Kinetic Model.

Recently, a pyrolysis process has been adapted as an emerging technology to convert metalized food packaging plastics waste (MFPWs) into energy products with a high economic benefit. In order to upscale this technology, the knowledge of the pyrolysis kinetic of MFPWs is needed and studying these parameters using free methods is not sufficient to describe the last stages of pyrolysis. For a better understanding of MFPWs pyrolysis kinetics, independent parallel reactions (IPR) kinetic model and its modification model (MIPR) were used in the present research to describe the kinetic parameters of MFPWs pyrolysis at different heating rates (5-30 °C min).

Molecular characterization, catalytic, kinetic and thermodynamic properties of protease produced by a mutant of Bacillus cereus-S6-3.

The proteolytic strain Bacillus cereus-S6-3 was subjected to mutagenic treatments viz. UV irradiations and methyl methane sulfonate (MMS). The obtained mutant strain, B.

Improving the catalytic, kinetic and thermodynamic properties of Bacillus subtilis KU710517 milk clotting enzyme via conjugation with polyethylene glycol.

Milk clotting enzyme (MCE) produced by Bacillus subtilis KU710517 was conjugated to several activated polysaccharides. Among all the conjugates, the enzyme conjugated with polyethylene glycol (PEG) exhibited the highest retained activity (551U/mg protein) with a recovered activity of 95.3%.

Structural characterization, catalytic, kinetic and thermodynamic properties of Keratinase from Bacillus pumilus FH9.

Bacillus pumilus FH9 keratinase was purified to homogeneity with a 59.9% yield through a series of three steps. The purified enzyme was a monomeric protein with a molecular mass around 50kDa and containing 7.

Catalytic, kinetic and thermodynamic properties of stabilized Bacillus stearothermophilus alkaline protease.

Bacillus stearothermophilus alkaline protease was conjugated to several oxidized polysaccharides of different chemical structure. The conjugates were evaluated for the kinetic and thermodynamic stability. The conjugated enzyme with oxidized pectin had the highest retained activity (79.

Structural characterization, catalytic, kinetic and thermodynamic properties of Aspergillus oryzae tannase.

Tannase (EC.3.1.

Catalytic, kinetic and thermodynamic properties of Bacillus pumilus FH9 keratinase conjugated with activated pectin.

Bacillus pumilus FH9 keratinase was covalently coupled to several oxidized polysaccharides. The conjugates were evaluated for the retained activity, kinetic and thermodynamic stability. Among all preparations, the conjugated enzyme with oxidized pectin had the highest recovered activity (71.

Study of Interleukin 28B rs12979860 and rs8099917 Polymorphisms and T-helper 1 Response in Hepatitis C Virus Patients.

HCV infection is a serious public health problem and a leading cause of chronic liver disease. It affects nearly 3% of the world's population with an associated high mortality. Egypt has the highest prevalence of HCV infection in the world (estimated at >10%).

Catalytic and thermodynamic properties of glycosylated Bacillus cereus cyclodextrin glycosyltransferase.

Cyclodextrin glycosyltransferase (CGTase) was covalently coupled to five oxidized polysaccharides differing in structure and chemical nature. The conjugates were evaluated for the retained activity, kinetic and thermodynamic stability. The conjugated CGTase with oxidized dextran (MW 47000) had the highest retained specific activity (70.

Treatment of subtalar calcanean fractures using trans-osseous limited lateral approach.

Background: Calcaneal fractures are the most common fractures of the tarsal bones. The majority of these fractures are produced by axial force like a fall from a height. Controversy still exists on the best line of treatment.

Biosynthesis of cyclodextrin glucosyltransferase by the free and immobilized cells of Bacillus cereus NRC7 in batch and continuous cultures.

Aims: The objective of this study was to enhance the production of cyclodextrin glucanotransferase (CGTase) produced by a local isolate Bacillus cereus NRC7.

Methods And Results: In batch culture, maximal CGTase activity (69·0 U ml(-1)) was reached after 24-h incubation period. In continuous production of CGTase by the free cells of B.

Catalytic properties of the immobilized Aspergillus tamarii xylanase.

Xylanase from Aspergillus tamarii was covalently immobilized on Duolite A147 pretreated with the bifunctional agent glutaraldehyde. The bound enzyme retained 54.2% of the original specific activity exhibited by the free enzyme (120 U/mg protein).

Stabilization of cellobiase by covalent coupling to soluble polysaccharide.

Cellobiase from Aspergillus niger was glycosylated by covalent coupling to cyanogen bromide activated dextran. The conjugated enzyme retained 62% of the original specific activity exhibited by the native cellobiase. The optimum pH as well as the pH stability of the conjugated form remain almost the same as for the native enzyme.

Purification and properties of three cellobiases from Aspergillus niger A20.

Three cellobiases, here called cellobiase A, B, and C, from the culture filtrate of Aspergillus niger A20, were purified by precipitation with ammonium sulphate, gel filtration through Sephadex G-75, and column chromatography of DEAE-cellulose. The purified enzymes were homogeneous on polyacrylamide disk electrophoresis. The mol wt of the purified enzymes were estimated by SDS-gel electrophoresis to be 88,000, 80,000, and 71,000 for cellobiases A, B, and C, respectively.

Utilization of water hyacinth cellulose for production of cellobiase-rich preparation by Aspergillus niger 1.

Production of a cellobiase-rich preparation by Aspergillus niger 1 was achieved using water hyacinth cellulose as the sole carbon source in the culture medium. Production of cellobiase, carboxymethylcellulase (CMC-ase) and filter paper (FP)-cellulase was favoured by controlling the pH of the culture medium during fermentation at 5.0.

Immobilization of Aspergillus niger NRC 107 Xylanase and beta-Xylosidase, and Properties of the Immobilzed Enzymes.

Aspergillus niger NRC 107 xylanase and beta-xylosidase were immobilized on various carriers by different methods of immobilization, including physical absorption, covalent binding, ionic binding, and entrapment. The immobilized enzymes were prepared by physical adsorption on tannin-chitosan, ionic binding onto Dowex-50W, covalent binding on chitosan beads through glutaraldehyde, and entrapment in polyacrylamide had the highest activities. In most cases, the optimum pH of the immobilized enzymes were shifted to lower than those of free enzymes.

Production and properties of fibrinolytic enzyme fromStreptomyces sp. NRC 411.

Of 16Streptomyces spp. investigated for the production of extracellular fibrinolytic enzyme, one species was chosen as the most promising producer. Using shaken cultures grown for 7 days, optimal conditions for enzyme production were pH 6.