Visualization of the action of ligninolytic enzymes on high yield pulp fibers

High-yield pulps from wheat straw and from poplar wood were treated with manganese-peroxidase (MnP) or with laccase (Lac), before and after a second refining stage

Получение на поверхности высокохромистых сталей карбидоупрочняемых диффузионных слоев заданного уровня свойств

The paper shows theoretical substantiated possibility to obtain high-quality carbide strengthening diffusion layers on the surface of high-chromium steel and the fields of their practical application.В статье представлена теоретически обоснованная возможность получения на поверхности высокохромистых сталей качественных карбидоупрочняемых диффузионных слоев, а также области их практического использования

REX-ISOLDE: post-accelerated radioactive BEAMS at CERN-ISOLDE

The ISOLDE RIB-facility at CERN has today been producing a vast range of radioactive beams since more than 30 years. The low-energy beams of ISOLDE will be complemented by a post-accelerator, REX-ISOLDE, currently being assembled. In order to convert the pseudo-DC, singly-charged beam from the ISOLDE mass separators into a cooled and bunched beam at higher charge states a novel scheme of trapping, cooling and charge-state breeding has been devised, using a linear Penning trap and an Electron Beam Ion Source (EBIS). This allows for subsequent acceleration by a short, cost-effective LINAC consisting of an RFQ, an IH-structure and three seven-gap resonators, reaching 0.8 - 2.2 MeV/u. The installation of REX-ISOLDE is well underway and the first post-accelerated radioactive beams are expected to be obtained during late 2000

Metals Accumulation in Marine Bivalves and Seawater from theLagoon of Boughrara in Tunisia (North Africa)

Since 1994 the lagoon of Boughrara located in the south western coast of Tunisia was a seat of repeated episodes of harmful algal proliferation. Due to intoxications by shellfish harvested in this region the area was banned. In order to estimate the metal contribution to this phenomenon, seawater and bivalves collected from Boughrara during the algal bloom period were analysed for Cd, Cr, Hg, Pb, Cu and Al content using the atomic absorption spectrometry.The average of the metals and heavy metals concentrations in clams flesh and shells were lower or in the range of the European Union regularity limits and exhibited the following decreasing order: Al>Cu>Cd>Cr>Pb>Hg. Levels were ranging between 11.541 mg/kg and 0.025 mg/kg wet weights. For seawater and inter-shell water the order was approximately the same. The lagoon of Boughrara might be considered relatively unpolluted with metals and repeated toxic algal proliferations remained unexplained

Molecular cloning of the cDNA encoding laccase from Pycnoporus cinnabarinus I-937 and expression in Pichia pastoris

International audienc

Combined cytotoxicity and genotoxicity of a marine toxin and seafood contaminant metal ions (chromium and cadmium)

International audienceno abstrac

Molecular cloning of the cDNA encoding laccase from Pycnoporus cinnabarinus I-937 and expression in Pichia pastoris

International audienc

Metabolic pathways of biotransformation and biosynthesis of aromatic compounds for the flavour industry by the basidiomycete Pycnoporus cinnabarinus

Among filamentous fungi, white-rot Basidiomycetes have become a strategic group to generate industrial aromatic flavours. In the course of a basidiomycete screening, the biotechnological potential of #Pycnoporus cinnabarinus strains was studied in order to produce, by transformation or de novo, natural aromatic flavours in liquid cultures. Ferulic acid and L-phenylalanine were found to be suitable substrates for vanillin and benzaldehyde (bitter almond aroma) production, respectively. These strains were also capable of producing de novo methylanthranilate, which has been described as the organoleptic note of wood strawberry. However, strains of #P. cinnabarinus often expressed laccase activity, which was unfavourable because the pathway to aromatic flavours is bypassed. To overcome this problem, the selection of monokaryotic laccase-deficient strains from basidiospores by classical genetics allowed to obtain more productive and more stable mycelial lines. (Résumé d'auteur