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1.
Int J Biol Macromol ; 129: 571-578, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30753879

RESUMO

A novel extracellular xylanase was purified and characterized from Pediococcus acidilactici GC25 (GenBank number: MF289522). The purification was 4.6-fold with a yield of 43.61% through acetone precipitation, Q-Sepharose, and CM-Sepharose ion change chromatography. The molecular weight of the enzyme was 48.15 kDa, and the optimum pH and temperature were 7.0 and 40 °C, respectively. The maximum activity was observed between 20 and 50 °C. Although it was active within a wide pH range (pH 2.0-9.0), it retained over 85% of its activity after 24 h incubation; and over 70% of its activity after 168 h incubation in neutral and alkaline pH. It was observed that the enzyme showed high stability with K+, Ba2+, Cd2+, Co2+, Sr2+, Mg2+, Ca2+, Al3+, Zn2+, and Ni2+ ions. The Km and Vmax for the xylanase were 3.10 mg mL-1 and 4.66 U/mg protein, respectively. It was determined that treatment of different fruit juices with P. acidilactici GC25 xylanase improved the clarification. The highest increase in the reducing sugar amount and decrease in the turbidity was 24.47 ±â€¯1.08 and 21.22 ±â€¯0.58 for peach juice at 0.15 U/mL enzyme concentration. These results showed that the xylanase purified from P. acidilactici GC25 may have a wide potential in biotechnological processes of the food and baking industry.


Assuntos
Endo-1,4-beta-Xilanases/isolamento & purificação , Endo-1,4-beta-Xilanases/metabolismo , Manipulação de Alimentos , Sucos de Frutas e Vegetais , Pediococcus acidilactici/enzimologia , Estabilidade Enzimática , Espaço Extracelular/metabolismo , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Metais/farmacologia , Pediococcus acidilactici/citologia , Temperatura
2.
J Environ Biol ; 36(6): 1319-24, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26688967

RESUMO

In the present study, cellulase was purified and characterized from Anoxybacillus gonensis (Gen bank Number: KM596794) which was isolated and characterized from Agri Diyadin Hot spring. It was found to synthesize cellulase which had a wide range of industrial applications. Twenty four-hour-cultured bacteria induced cellulase production and specific activities during the purification steps were 1.47, 81.06 and 109.4 EU mg(-1) protein at crude extract, ammonium sulphate precipitated and DEAE-Sephadex purification steps. The highest enzyme activity was observed at 50°C and the optimum range of pH was 3-10. Molecular weight of enzyme was determined approximately 40kDa. The kinetic parameters of cellulase against carboxymethylcellulose (CMC) were 153.4 pmol min(-1) mg for Vmax and 0.46mM for Km. Among effectors of the enzyme, Zn2+, Ca2+, Co2+ and EDTA decreased enzyme activity.


Assuntos
Anoxybacillus/enzimologia , Celulases/metabolismo , Anoxybacillus/metabolismo , Celulases/genética , Regulação Bacteriana da Expressão Gênica/fisiologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Fontes Termais , Cinética , Especificidade por Substrato , Temperatura
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