Publications by authors named "Guillermo Aguilar Osorio"

A 32-fold increase in laccase activity production by the thermophilic biomass-degrading fungus Co3Bag1 was achieved when the microorganism was grown on a modified medium containing fructose, sodium nitrate, and copper. A 70 kDa laccase (LacA), produced under the above conditions, was purified, immobilized in copper alginate gel beads, and characterized. LacA, both free and immobilized enzymes, exhibited optimal activity at pH 3.

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Blastocystis sp. is a common intestinal microorganism. The α-L-fucosidase (ALFuc) is an enzyme long associated with the colonization of the gut microbiota.

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Biochemical characterization of polyphenol oxidase (PPO) present in purple sweet potato (PSP) is a key step in developing efficient methodologies to control oxidative damage caused by this enzyme to the valuable components of PSP, such as caffeoylquinic acid derivatives and acylated anthocyanins. Thus, this work focused on the assessment of the effects of pH, temperature, and chemical agents on the PPO activity as well as characterization of the PPO substrate specificity towards major phenolic compounds found in PSP. The optimum conditions of enzyme activity were pH 7 and a temperature range of 20-30 °C at which phenolic substrates were oxidized with 72.

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Two strains of one toxigenic (CECT 2687) and the other non-toxigenic (NRRL 6541) were studied for their genomic potential, growth capacity, and the production of enzymes on simple sugars, polysaccharides, and complex substrates under solid-state fermentation (SSF). According to the genome analysis, this fungus has many genes to degrade different types of polysaccharides and therefore it would be able to grow on different substrates. Both strains grow in all the carbon sources, but visibly CECT2687 grows slower than NRRL6541.

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FP-500 is a Mexican native strain that has been reported as a good producer of xylanases and pectinases; therefore, it promises a strong impact on biotechnology. To provide an overview of protein secretion by , we carried out a comparative proteome analysis of extracellular proteins in liquid cultures with two heterogeneous agro-industrial residues; corn cob (CC) and wheat bran (WB), as carbon sources. Extracellular proteins obtained from both cultures were identified using MS/MS spectrometry.

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Pigmented maize has been extensively studied due to its high anthocyanin content. This study has been focused mainly on kernel, although the whole plant of purple corn is a potential source of anthocyanins. First, general parameters of extraction (solvent system, solvent-to-solid ratio, number of extractions, and acid type) were established depending on the total anthocyanins content.

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ssp. 25124 (25124) is a lactic acid bacterium (LAB) isolated from , a refreshing beverage prepared by suspending fermented (a thermal and alkali-treated maize dough) in water. Although s are the predominant strains in fermented doughs, such as sourdoughs, and non-nixtamalized fermented maize foods, the microbiota is markedly different.

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Background: The fungal genus Aspergillus is of critical importance to humankind. Species include those with industrial applications, important pathogens of humans, animals and crops, a source of potent carcinogenic contaminants of food, and an important genetic model. The genome sequences of eight aspergilli have already been explored to investigate aspects of fungal biology, raising questions about evolution and specialization within this genus.

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The viability of the scaling-up of pectinases production by Aspergillus flavipes at 5L-bioreactor scale has been demonstrated by keeping constant the power input, and a drastic increase in the endo- and exopectinolytic enzyme production was recorded (7- and 40-fold, respectively). The main process variables were modelled by means of logistic and Gompertz equations. In order to overcome the limitations of the conventional downstream strategies, a novel extraction strategy was proposed on the basis of the adequate salting-out potential of two biocompatible cholinium-based ionic liquids (NCl and NHPO) in aqueous solutions of Tergitol, reaching more than 90% of extraction.

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Article Synopsis
  • A thermostable xylanase enzyme (TtXynA) was extracted from T. terrestris Co3Bag1 and exhibits optimal activity at 85 °C and pH 5.5.
  • TtXynA retains over 90% activity across a pH range of 4.5-10 and has a long half-life of 23.1 days at 65 °C, demonstrating high thermal stability.
  • This enzyme displays strong activity on beechwood xylan, producing various sugars, and is the first reported hyperthermophilic xylanase from T. terrestris, indicating potential for use in high-temperature biotechnological processes like bioethanol production.
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Unlabelled: Polyurethane (PU) is widely used in many aspects of modern life because of its versatility and resistance. However, PU waste disposal generates large problems, since it is slowly degraded, there are limited recycling processes, and its destruction may generate toxic compounds. In this work, we isolated fungal strains able to grow in mineral medium with a polyester PU (PS-PU; Impranil DLN) or a polyether PU (PE-PU; Poly Lack) varnish as the only carbon source.

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Background: Plant biomass is the major substrate for the production of biofuels and biochemicals, as well as food, textiles and other products. It is also the major carbon source for many fungi and enzymes of these fungi are essential for the depolymerization of plant polysaccharides in industrial processes. This is a highly complex process that involves a large number of extracellular enzymes as well as non-hydrolytic proteins, whose production in fungi is controlled by a set of transcriptional regulators.

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Glucose kinases (Glks) are enzymes of the glycolytic pathway involved in glucose phosphorylation. These enzymes can use various phosphoryl donors such as ATP, ADP, and polyphosphate. In several streptomycetes, ATP-glucose kinase (ATP-Glk) has been widely studied and regarded as the main glucose phosphorylating enzyme and is likely a regulatory protein in carbon catabolite repression.

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The presence of a mannitol cycle in fungi has been subject to discussion for many years. Recent studies have found no evidence for the presence of this cycle and its putative role in regenerating NADPH. However, all enzymes of the cycle could be measured in cultures of Aspergillus niger.

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The plant polysaccharide degradative potential of Aspergillus nidulans was analysed in detail and compared to that of Aspergillus niger and Aspergillus oryzae using a combination of bioinformatics, physiology and transcriptomics. Manual verification indicated that 28.4% of the A.

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Growth and enzymes production by Aspergillus flavipes FP-500 were evaluated on pectin, polygalacturonic acid, galacturonic acid, arabinose, rhamnose, xylose, glycerol and glucose at different initial pH values. We found that the strain produced exopectinases, endopectinases and pectin lyases. Exopectinases and pectin lyase were found to be produced at basal levels as constitutive enzymes and their production was modulated by the available carbon source and pH of culture medium and stimulated by the presence of inducer in the culture medium.

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