Purification and Characterization of the alpha-Glucosidase Produced by Thermophilic Fungus Thermoascus aurantiacus CBMAI 756

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Production of Crude Xylanase from Thermoascus Aurantiacus CBMAI 756 Aiming the Baking Process

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Purification and characterization of polygalacturonase produced by thermophilic Thermoascus aurantiacus CBMAI-756 in submerged fermentation

An extracellular polygalacturonase was isolated from 5-day culture filtrates of Thermoascus aurantiacus CBMAI-756 and purified by gel filtration and ion-exchange chromatography. The enzyme was maximally active at pH 5.5 and 60-65 degrees C. The apparent K (m) with citrus pectin was 1.46 mg/ml and the V (max) was 2433.3 mu mol/min/mg. The apparent molecular weight of the enzyme was 30 kDa. The enzyme was 100% stable at 50 degrees C for 1 h and showed a half-life of 10 min at 60 degrees C. Polygalacturonase was stable at pH 5.0-5.5 and maintained 33% of initial activity at pH 9.0. Metal ions, such as Zn+2, Mn+2, and Hg+2, inhibited 50, 75 and 100% of enzyme activity. The purified polygalacturonase was shown to be an endo/exo-enzyme, releasing mono, di and tri-galacturonic acids within 10 min of hydrolysis.

Produção de enzimas celulolíticas pelos fungos thermoascus aurantiacus CBMAI 756, thermomyces lanuginosus, Trichoderma reesei QM9414 e Penicillium viridicatum RFC3 e aplicação na sacarificação do bagaço de cana de açucar com diferentes pré-tratamentos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Purificação e caracterização bioquímica da α-glicosidase termoestável produzida por Thermoascus aurantiacus CBMAI 756

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Purification and properties of polygalacturonase produced by thermophilic fungus Thermoascus aurantiacus CBMAI-756 on solid-state fermentation

Polygalacturonases are enzymes involved in the degradation of pectic substances, being extensively used in food industries, textile processing, degumming of plant rough fibres, and treatment of pectic wastewaters. Polygalacturonase (PG) production by thermophilic fungus Thermoascus aurantiacus on solid-state fermentation was carried out in culture media containing sugar cane bagasse and orange bagasse in proportions of 30% and 70% (w/w) at 45°C for 4 days. PG obtained was purified by gel filtration and ion-exchange chromatography. The highest activity was found between pH 4.5 and 5.5, and the enzyme preserved more than 80% of its activity at pH values between 5.0 and 6.5. At pH values between 3.0 and 4.5, PG retained about 73% of the original activity, whereas at pH 10.0 it remained around 44%. The optimum temperature was 60–65°C. The enzyme was completely stable when incubated for 1 hour at 50°C. At 55°C and 60°C, the activity decreased 55% and 90%, respectively. The apparent molecular weight was 29.3 kDa, Km of 1.58 mg/mL and Vmax of 1553.1μmol/min/mg. The presence of Zn+2, Mn+2, and Hg+2 inhibited 59%, 77%, and 100% of enzyme activity, respectively. The hydrolysis product suggests that polygalacturonase was shown to be an endo/exoenzyme.

Production and characteristics comparison of crude beta-glucosidases produced by microorganisms Thermoascus aurantiacus e Aureobasidium pullulans in agricultural wastes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of a thermoascus aurantiacus thermostable enzyme cocktail on wheat bread quality

Thermophilic fungus Thermoascus aurantiacus (CBMAI 756) on solid-state fermentation using corncob as a nutrient source produces an enzyme pool with the potential to be used in bread making. In this paper, the use of this enzyme cocktail as a wheat bread improver was reported. Both products released by flour arabinoxylan degradation and bread quality were investigated. The main product released through enzyme activity after prolonged incubation was xylose indicating the presence of xylanase; however, a small amount of xylobiose and arabinose also confirmed the presence of xylosidase and α-L- arabinofuranosidase, respectively. Enzyme mixture in vitro mainly attacked water-unextractable arabinoxylan contributing to beneficial effect in bread making. The use of an optimal enzyme concentration (35 U xylanase/100 g of flour) increased specific volume (22%), reduced crumb firmness (25%), and reduced amylopectin retrogradation (17%) during bread storage. In conclusion, the enzyme cocktail produced by T. aurantiacus CBMAI 756 can improve wheat bread quality. © 2013 Elsevier Ltd.

Aplicação de β-glicosidases produzidas pelos microorganismos Aureobasidium pullulans e Thermoascus aurantiacus ao processo fermentativo da aguardente de cana com foco na produção de terpenos

Pós-graduação em Alimentos e Nutrição - FCFAR

Aplicação de xilanase e/ou ciclodextria glicotransferase (CGTase) na produção de pães

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Purification and characterization of an alpha-D-glucuronidase from a thermophilic fungus, Thermoascus aurantiacus

An alpha-D-glucuronidase was purified from the culture filtrates of Thermoascus aurantiacus. A simple colorimetric method for its assay is reported. The enzyme is a single polypeptide chain with a molecular weight of 118,000. It acts optimally at pH 4.5. It shows maximum activity at 65 degrees C. The t 1/2 at 70 degrees C was 40 min. It specifically cleaved the alpha-(1----2) linkage between 4-O-methyl-alpha-D-glucuronic acid and the xylose residue in xylan and several glucurono-xylooligosaccharides.

Crystallization and Preliminary X-ray Diffraction Analysis of Crystals of Thermoascus aurantiacus Xylanase

Crystals suitable for high resolution X-ray diffraction analysis have been grown of the 29,774-Da protein, xylanase (1,-4-beta-xylan xylanohydrolase EC 3.2.1.8) from the thermophilic fungus Thermoascus aurantiacus. This protein, an endoxylanase demonstrates the hydrolysis of β-(1-4)-Image -xylose linkage in xylans and crystallizes as monoclinic pinacoids in the presence of ammonium sulphate buffered at pH 6·5, and also with neutral polyethylene glycol 6000. The crystals belong to space group P 21 and have cell dimensions, a = 41·2 Å, b = 67·76 Å, c = 51·8 Å; β = 113·2°.

Production and characterization of polygalacturonase from thermophilic Thermoascus aurantiacus on submerged fermentation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)