scholarly journals Porous poly(urethane urea) microparticles for immobilization of maltogenic α amylase from Bacillus stearothermophilus

Chemija ◽  
2021 ◽  
Vol 32 (3-4) ◽  
Author(s):  
Antanas Strakšys ◽  
Tatjana Kochanė ◽  
Sandra Mačiulytė ◽  
Saulutė Budrienė
Keyword(s):  
Bacillus Stearothermophilus ◽  
Physical Adsorption ◽  
Covalent Attachment ◽  
Molar Ratio ◽  
Poly Vinyl Alcohol ◽  
Synthesis Time ◽  
Food Industries ◽  
Activity Temperature ◽  
Residual Stability ◽  
Porous Poly

Maltogenic α amylase from Bacillus stearothermophilus (BsMa) was immobilized by covalent attachment and physical adsorption onto porous poly(urethane urea) (PUU) microparticles obtained from poly(vinyl alcohol) (PVA) and 4,4’-methylenebis(cyclohexyl diisocyanate) (H12DI) by onepot synthesis. The influence of PUU synthesis parameters such as PVA and H12DI molar ratio, synthesis time and temperature on porosity, surface area, structure of microparticles and catalytic activity and stability of immobilized BsMa was investigated. The highest efficiency of the immobilization of BsMa onto the PUU carrier was 97% and the highest residual stability of the immobilized enzyme reached 95% after 28 days of storage at 4°C. The optimal activity temperature of immobilized BsMa was at 80°C and it was higher than that of native enzyme. Effects of ionic strength and repetitive batch processing cycles on the activity of immobilized BsMa were also studied. Immobilization of BsMa onto PUU carriers has a great potential for biotechnology and food industries.

scholarly journals Recent Strategies and Applications for l-Asparaginase Confinement

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 5827
Author(s):  
João C. F. Nunes ◽  
Raquel O. Cristóvão ◽  
Mara G. Freire ◽  
Valéria C. Santos-Ebinuma ◽  
Joaquim L. Faria ◽  
...  
Keyword(s):  
Half Life ◽  
Physical Adsorption ◽  
Blood System ◽  
Covalent Attachment ◽  
Nano Materials ◽  
Food Sector ◽  
Food Industries ◽  
Pharmaceutical Application ◽  
Life Enhancement ◽  
First Time

l-asparaginase (ASNase, EC 3.5.1.1) is an aminohydrolase enzyme with important uses in the therapeutic/pharmaceutical and food industries. Its main applications are as an anticancer drug, mostly for acute lymphoblastic leukaemia (ALL) treatment, and in acrylamide reduction when starch-rich foods are cooked at temperatures above 100 °C. Its use as a biosensor for asparagine in both industries has also been reported. However, there are certain challenges associated with ASNase applications. Depending on the ASNase source, the major challenges of its pharmaceutical application are the hypersensitivity reactions that it causes in ALL patients and its short half-life and fast plasma clearance in the blood system by native proteases. In addition, ASNase is generally unstable and it is a thermolabile enzyme, which also hinders its application in the food sector. These drawbacks have been overcome by the ASNase confinement in different (nano)materials through distinct techniques, such as physical adsorption, covalent attachment and entrapment. Overall, this review describes the most recent strategies reported for ASNase confinement in numerous (nano)materials, highlighting its improved properties, especially specificity, half-life enhancement and thermal and operational stability improvement, allowing its reuse, increased proteolysis resistance and immunogenicity elimination. The most recent applications of confined ASNase in nanomaterials are reviewed for the first time, simultaneously providing prospects in the described fields of application.

Porous Poly(vinyl alcohol)-Alginate Gel Hybrid Construct for Neocartilage Formation Using Human Nasoseptal Cells

2010 ◽  
Vol 163 (2) ◽  
pp. 331-336 ◽  
Author(s):  
David A. Bichara ◽  
Xing Zhao ◽  
Nathaniel S. Hwang ◽  
Hatice Bodugoz-Senturk ◽  
Michael J. Yaremchuk ◽  
...  
Keyword(s):  
Vinyl Alcohol ◽  
Poly Vinyl Alcohol ◽  
Alginate Gel ◽  
Hybrid Construct ◽  
Porous Poly

Porous Poly(1-naphthylamine) Synthesized by Interfacial Polymerization

2014 ◽  
Vol 809-810 ◽  
pp. 319-322
Author(s):  
Zhen Zhong Hou ◽  
Qing Hao Yang
Keyword(s):  
Interfacial Polymerization ◽  
Amorphous Polymer ◽  
Molar Ratio ◽  
Polymerization Temperature ◽  
Main Mode ◽  
Reaction Conditions ◽  
Ft Ir ◽  
Micro Morphology ◽  
Polymerization Method ◽  
Porous Poly

Porous poly (1-naphthylamine) were synthesized by interfacial polymerization method. The effects of several reaction conditions including oxidant/monomer molar ratio, polymerization temperature and reaction time on the polymerization yield have been investigated. The highest yield of poly (1-naphthylamine) was up to 73% at oxidant/monomer molar ratio of 3 and polymerization temperature of 25 °C for over 20h. Using FT-IR and XRD to analyze the structure of the obtained polymer, the results show that the main mode of connection for 1-naphthylamine units was linking N to para-C and it formed amorphous polymer with some ordered strutures. The micro-morphology of the polymer observed by SEM was found to have irregular porous structure with pore size less than 5μm, which may be related to the “self-emulsion effect” during polymerization.

Piezochromism of Porous Poly(vinyl alcohol)–Poly(vinyl acetate) Composite Film in Organic Solvents

1995 ◽  
Vol 176 (2) ◽  
pp. 370-377 ◽  
Author(s):  
Sadao Hayashi ◽  
Koji Asada ◽  
Satoshi Horiike ◽  
Hajime Furuhata ◽  
Toshihiro Hirai
Keyword(s):  
Composite Film ◽  
Vinyl Acetate ◽  
Organic Solvents ◽  
Vinyl Alcohol ◽  
Poly Vinyl Alcohol ◽  
Porous Poly

Simple Fabrication Method for a Porous Poly(vinyl alcohol) Matrix by Multisolvent Mixtures for an Air-Exposed Model of the Lung Epithelial System

Langmuir ◽  
2014 ◽  
Vol 30 (41) ◽  
pp. 12107-12113 ◽  
Author(s):  
Su-Kyoung Chae ◽  
Cho Hay Mun ◽  
Da-Yoon Noh ◽  
Edward Kang ◽  
Sang-Hoon Lee
Keyword(s):  
Vinyl Alcohol ◽  
Poly Vinyl Alcohol ◽  
Fabrication Method ◽  
Lung Epithelial ◽  
Porous Poly

A Study on the Preparation of PEG/FeOx Ferrofluids

2005 ◽  
Vol 475-479 ◽  
pp. 2271-2274 ◽  
Author(s):  
Shuchun Hu ◽  
Zuo Wan Zhou
Keyword(s):  
Polyethylene Glycol ◽  
Physical Adsorption ◽  
Reduction Reaction ◽  
Molar Ratio ◽  
Stirring Rate ◽  
Oxidation Reduction ◽  
Oxidation Reduction Reaction ◽  
Inorganic Components

As FeOx particles were prepared by oxidation-reduction reaction, the surfactant of polyethylene glycol (ab. PEG) was used to cover the FeOx particles, thus the PEG/FeOx ferrofluids were obtained. The morphology, structure and composition of the ferrofluids were investigated. The results show that the product is spheric in the shape, and the diameter of the product is obviously influenced by PEG content and slightly influenced by the stirring rate. When the content of PEG increases in the range of 50～350g/L, the diameter of the product decreases. However, when the content of PEG is in the range of 350～750g/L, the diameter increases with the increasing of PEG content. When the stirring rate is between 50 and 150r/min, the diameter of the product slightly decreases as the stirring rate increases. Moreover, the results demonstrate that the products are mainly constituted of PEG and FeOx, and the value of x in the formula of FeOx can be adjusted by controlling the molar ratio of H2O2 to Fe2+. Further analysis indicates that the organic and inorganic components of the PEG/FeOx ferrofluids are combined by both physical adsorption and coordinate combination.

Synthesis and characterization of mesoporous molecular sieves

2009 ◽  
Vol 63 (6) ◽  
Author(s):  
Michal Horňáček ◽  
Pavol Hudec ◽  
Agáta Smiešková
Keyword(s):  
Molecular Sieves ◽  
Physical Adsorption ◽  
Mesoporous Molecular Sieves ◽  
X Ray Diffraction ◽  
Synthesis Time ◽  
Adsorbed Pyridine ◽  
Adsorption Of Nitrogen ◽  
Temperature Programmed ◽  
Different Content ◽  
Mcm 41

AbstractIn the synthesis of mesoporous molecular sieves of the type MCM-41, different cationactive surfactants and sources of silicon were used. Moreover, Al-MCM-41 samples with different content of aluminium were synthesized. MCM-41 and Al-MCM-41 were synthesized at elevated temperature in stainless-steel autoclaves. Prepared mesoporous molecular sieves were characterized by powder X-ray diffraction (XRD), physical adsorption of nitrogen at the temperature of −197°C, sorption capacity of benzene, and by infrared spectroscopy (FTIR). Acidity was measured for Al-MCM-41 by temperature programmed desorption of ammonia (TPDA) and by FTIR of adsorbed pyridine. Acid catalytic activity of Al-MCM-41 was tested by isomerization of o-xylene. Influence of the synthesis reproducibility, surfactant used, source of silicon, synthesis time, source of aluminium, and Si to Al mole ratio on the properties of mesoporous molecular sieves were evaluated.

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