The aim of this study was to determine the effects of the essential oil of Thymus serpyllum L. and of its components thymol and total phenols (total phenolic content, TPC) extracted from the plant on the growth and mycotoxin production of Aspergillus ochraceus, A. carbonarius, and A. niger. Minimal inhibitory concentration (MIC) determined for the essential oil and thymol, and selected concentr...

The genera Aspergillus comprises species that produce mycotoxins such as aflatoxins, ochratoxins and patulin. These are cosmopolitan species, natural contaminants of agricultural products. In coffee grains, the most important Aspergillus species in terms of the risk of presenting mycotoxins belong to the genera Aspergillus Section Circumdati and Section Nigri. The purpose of this study was to a...

Aspergillus ochraceus, a thermotolerant fungus isolated in Brazil from decomposing materials, produced an extracellular β-xylosidase that was purified using DEAE-cellulose ion exchange chromatography, Sephadex G-100 and Biogel P-60 gel filtration. β-xylosidase is a glycoprotein (39 % carbohydrate content) and has a molecular mass of 137 kDa by SDS-PAGE, with optimal temperature and pH at 70 °C ...

Conidia of Aspergillus ochraceus convert progesterone into 11alpha-hydroxyprogesterone and 6beta, 11alpha-dihydroxyprogesterone. The conversion ability does not depend on the sporulation medium. Transformation depends on the strain and on the conidia concentration. Adaptation has never been observed. Age and storage of conidia, pH, aeration-agitation, nitrogen source, metal ions, chelating agen...

The xylanase biosynthesis is induced by its substrate-xylan. The high xylan content in some wastes such as wheat residues (wheat bran and wheat straw) makes them accessible and cheap sources of inducers to be mainly applied in great volumes of fermentation, such as those of industrial bioreactors. Thus, in this work, the main proposal was incorporated in the nutrient medium wheat straw particle...

Article history: Received on: 24/02/2016 Revised on: 12/04/2016 Accepted on: 07/05/2016 Available online: 28/06/2016 Silver nanoparticles (AgNPs) have potential antimicrobial activity against bacteria and fungi. The synthesis of AgNPs have been reported using several chemical and physical methods which are not friendly environment. Therefore, our technique has focused on the synthesis of AgNPs ...

A rapid method for preparing cell-free extracts of Aspergillus ochraceus was developed. Mycelial mats were prefrozen in liquid nitrogen, ground to a fine powder in a cold mortar, and homogenized in an all-glass mechanical homogenizer. This method provided preparations averaging 43.0 mg of protein per g of mycelium (wet weight). The method was fast, efficient, and did not subject the extract ...