Production of cellulolytic and hemicellulolytic enzymes by Aspergillus niger 3T5B8 mutants and parental strains in solid-state fermentation.

Several studies have sought to increase the efficiency of the enzymatic hydrolysis of lignocellulosic biomass. In this context, the improvement of strains producing cellulolytic and hemicellulolytic enzymes may result in more efficient enzymatic mixtures. The parent strain of Aspergillus niger 3T5B8, referred as a polygalacturonase producer, was used for genetic improvement in order to increase the production of cellulases and hemicellulases. The production of the enzymes CMCase, xylanase, beta-glucosidase and polygalacturonase by solid-state fermentation using two mutant strains P49 and P83 was evaluated and compared with the parental strain. The results showed a prominence for the P83 strain with an increase in the production of 174% for xylanase and 402% for polygalacturonase.SINAFERM; SHEB. 3 a 6 de setembro. Seção Trabalhos. Ref. 56374

Flexible and reusable parylene C mask technology for applications in cascade impactor air quality monitoring systems

The development of traceable new methodologies to quantify elemental air pollutants in particulate matter (PM) supports modernization of methods used in air quality monitoring networks in Europe. In the framework of the EURAMET EMPIR AEROMET II project, the combination of cascade impactor aerosol sampling and total reflection X-ray fluorescence elemental spectroscopy (TXRF) was investigated. This technique requires a traceable calibration based on reference samples. This paper describes a new, simple and effective method to produce such reference samples using flexible, reusable, and low-cost parylene C shadow masks, fabricated by photolithographic steps. These shadow masks can be used to produce reference samples that mimic the Dekati cascade impactor's deposition patterns by applying as-prepared micro stencils to 30 mm acrylic substrates and evaporating a reference material (Ti) in arrangements of thin circular dots. The highly flexible direct patterning of acrylic discs with reference material, otherwise impossible with conventional photolithography, allows multiple reusing of the same micro stencils. The aspect ratios of the dots could be repeated with an error less than 4%. A first set of standard reference samples for the 13 stages of the Dekati cascade impactor was produced and preliminary TXRF measurements of the deposited Ti masses were performed. The centricity of the deposition patterns turned out to be an important parameter for the quality of the TXRF results. The parylene mask technology for the production of reference samples turns out to be a promising new approach for the traceable calibration of TXRF spectrometers for the quantification of element concentrations in environmental aerosol samples but, due to its great versatility, it could be used for several other micropatterning applications on conventional and unconventional substrates

Use of asparaginase in reducing free asparagine formation in coffee beans.

P.FT.3