Thermal Inactivation
Mostrando 1-12 de 268 artigos, teses e dissertações.
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1. Kinetic characterization, thermal and pH inactivation study of peroxidase and pectin methylesterase from tomato (Solanum betaceum)
Abstract Peroxidase (POD) and pectin methylesterase (PME) from tomato were characterized, studied thermal stability, and analyzed the synergistic effect of temperature and pH. For POD, the optimal activity, using H2O2 as substrate and ABTS+• as the donor H+, was obtained at pH 3.5, and for PME, the optimal activity using pectin as substrate was obtained at
Food Sci. Technol. Publicado em: 2020-06
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2. Effect of Blanching on Enzyme Activity and Bioactive Compounds of Blackberry
ABSTRACT The inactivation of peroxidase and polyphenol oxidase and the degradation of phenolic compounds, anthocyanins, and antioxidant activity in blackberry were investigated during blanching in water at 80-90 °C, and in steam, from 0 to 10 minutes. The enzyme kinetics indicated the presence of two isoenzymes with different thermal stability, following tw
Braz. arch. biol. technol.. Publicado em: 14/11/2018
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3. Kinetics and Thermodynamics of Thermal Inactivation of β-Galactosidase from Aspergillus oryzae
ABSTRACT For optimization of biochemical processes in food and pharmaceutical industries, the evaluation of enzyme inactivation kinetic models is necessary to allow their adequate use. Kinetic studies of thermal inactivation of β-galactosidase from Aspergillus oryzae were conducted in order to critically evaluate mathematical equations presented in the lite
Braz. arch. biol. technol.. Publicado em: 13/09/2018
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4. PEROXIDASE FROM SOYBEAN MEAL: OBTENTION, PURIFICATION AND APPLICATION IN REDUCTION OF DEOXYNIVALENOL LEVELS
This study established the conditions for the extraction of the enzyme peroxidase (PO) from soybean meal (SBM). An experimental design methodology was carried out in order to evaluate the effects of stirring rate time, pH and extracting solvent volume on the enzyme extraction. By using 5 g SBM and 50 mL phosphate buffer 10 mmol L-1 pH 4.7, 60 min stirring ra
Quím. Nova. Publicado em: 2017-09
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5. Thermal inactivation studies on toxic seeds from fruits of the Brazilian Central Plain
Abstract Seeds from endemic Brazilian fruits (Mangaba, Cagaita, Jatobá and Araticum), previously confirmed to be toxic using Artemia salina bioassay were exposed to different temperatures and heating times aiming to test inhibitory effects on toxicity, as a first approach to characterize and identify toxic compounds and their thermal stability. After treatm
Food Sci. Technol. Publicado em: 19/09/2016
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6. Thermal inactivation kinetics of partially purified mango pectin methylesterase
Abstract Kinetic parameters of thermal inactivation of pectin methylesterase (PME) in a partially purified mango enzyme extract were determined. The PME of mango partially purified by salting out showed different patterns of thermal inactivation, indicating the presence of a thermostable fraction at 70 °C and a thermolabile fraction at lower temperatures. T
Food Sci. Technol. Publicado em: 30/06/2016
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7. Chemical modification of Aspergillus nigerβ-glucosidase and its catalytic properties
Aspergillus niger β-glucosidase was modified by covalent coupling to periodate activated polysaccharides (glycosylation). The conjugated enzyme to activated starch showed the highest specific activity (128.5 U/mg protein). Compared to the native enzyme, the conjugated form exhibited: a higher optimal reaction temperature, a lower Ea (activation energy), a h
Braz. J. Microbiol.. Publicado em: 2015-03
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8. The superoxide anion donor, potassium superoxide, induces pain and inflammation in mice through production of reactive oxygen species and cyclooxygenase-2
It is currently accepted that superoxide anion (O2•−) is an important mediator in pain and inflammation. The role of superoxide anion in pain and inflammation has been mainly determined indirectly by modulating its production and inactivation. Direct evidence using potassium superoxide (KO2), a superoxide anion donor, demonstrated that it induced thermal
Braz J Med Biol Res. Publicado em: 13/02/2015
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9. Characteristics of Immobilized Urease on Grafted Alginate Bead Systems
This study evaluated the biological importance of immobilized urease enzyme over the free urease. The support material used for urease immobilization was alginate. Generally, the immobilization of urease in alginate gel showed a marked increase in Km and Vmax. However, the immobilized urease showed higher thermal stability than that of free enzyme. The rate
Braz. arch. biol. technol.. Publicado em: 13/01/2015
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10. Thermal inactivation of polyphenoloxidase and peroxidase in Jubileu clingstone peach and yeast isolated from its spoiled puree
The thermal inactivation of yeast isolated from spoiled Jubileu peach puree and that of polyphenoloxidase (PPO) and peroxidase (POD) in cv. Jubileu, which is widely cultivated in southern Rio Grande do Sul state, Brazil, were studied. PPO and POD were extracted using the protein powder method and submitted to partial purification by precipitation followed by
Food Sci. Technol. Publicado em: 2014-03
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11. Biochemical studies on immobilized fungal β-glucosidase
β-Glucosidase from Aspergillus niger was immobilized on sponge by covalent binding through a spacer group (glutaraldehyde). Sponge-immobilized enzyme had the highest immobilization yield (95.67%) and retained 63.66% of the original activity exhibited by the free enzyme. The optimum pH of the immobilized enzyme remains almost the same as for the free enzyme
Braz. J. Chem. Eng.. Publicado em: 2013-12
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12. Immobilized Lactobacillus acidophilus produced from whey and alginate
An analysis was made of the use of whey fermentation by Lactobacillus acidophilus LA-5 for encapsulated probiotic bacteria cell production. Fermentation was done in a 2-liter Biostat B Fermentor at 28±1 ºC without air supply and agitation maintained at 200 rpm. Different processing conditions were studied using Center Composite Design applied to Surface Re
Braz. J. Chem. Eng.. Publicado em: 2013-06