The CPLEAR detector at CERN

The CPLEAR collaboration has constructed a detector at CERN for an extensive programme of CP-, T- and CPT-symmetry studies using ${\rm K}^0$ and $\bar{\rm K}^0$ produced by the annihilation of $\bar{\rm p}$'s in a hydrogen gas target. The ${\rm K}^0$ and $\bar{\rm K}^0$ are identified by their companion products of the annihilation ${\rm K}^{\pm} \pi^{\mp}$ which are tracked with multiwire proportional chambers, drift chambers and streamer tubes. Particle identification is carried out with a liquid Cherenkov detector for fast separation of pions and kaons and with scintillators which allow the measurement of time of flight and energy loss. Photons are measured with a lead/gas sampling electromagnetic calorimeter. The required antiproton annihilation modes are selected by fast online processors using the tracking chamber and particle identification information. All the detectors are mounted in a 0.44 T uniform field of an axial solenoid of diameter 2 m and length 3.6 m to form a magnetic spectrometer capable of full on-line reconstruction and selection of events. The design, operating parameters and performance of the sub-detectors are described.

Screening of strains of Lentinula edodes grown on model olive mill wastewater in solid and liquid state culture for polyphenol biodegradation

In Morocco, the olive industry produces great amounts of olive mill wastewater (OMW) yearly in a short period (250 000 m(3) of liquid wastes in four months, November-February). Phenolic compounds are largely responsible for the phytotoxicity and antimicrobial effects of OMW. Several studies have been carried out on biological and enzymatic treatments of OMW. However, the use of OMW to produce value-added products, e.g. mushroom cultivation, are less explored. This research aimed to select shiitake mushroom strains capable of growing on OMW, involving decolorization, removal of total phenol, and high production of mycelial biomass. Sixteen strains of Lentinula edodes were evaluated for their tolerance to OMW, apical growth rate, and biomass production on agar media. The highest biomass yields were recorded in four strains (Le118, Le119, Le121, Le122) grown in the presence of 20% (v/v) OMW. The ability of these pre-selected strains to decolorize and to remove total phenol from OMW was then assessed in liquid culture, without nutritional supplements. The strain Le119 of L edodes showed 65% decolorization, and 75% elimination of total phenol according to the Folin-Ciocalteu assay. Laccase production was the main lignolytic activity observed, and one of its isoforms stained on native PAGE with p-phenylenediamine as substrate at pH 5.0

Biomass, laccase and endoglucanase production by Lentinula edodes during solid state fermentation of reed grass, bean stalks and wheat straw residues

Mycelium growth rates, biomass concentration (estimated as glucosamine content) and laccase and endoglucanase secretion were monitored during solid state fermentation (SSF) of wheat straw (WS), reed grass (RG) and bean stalk (BS) residues by Lentinula edodes strains 119, 121, and 122. In a first experiment, these strains were subjected to screening regarding their growth rates and biomass yield, where strain 121 proved to be the fastest colonizer. However, the greater biomass yield at the end of colonization was demonstrated by strain 122 on BS (465.93 mg g(-1) d.w.). In a second experiment, growth characters, as well as endoglucanase and laccase production patterns of the selected strains 121 and 122 were monitored at three intervals i.e., at 33, 66, and 100% of substrate colonization. BS furnished the highest endoglucanase production for strain 121, while RG for strain 122. A strain and substrate-dependent behaviour of the enzyme secretion was detected, with strain 122 presenting maximal endoglucanase activity in all substrates at the initial (33%) and final (100%) stages of colonization (0.64-0.90 and 0.79-0.97 U g(-1,) respectively). However, in strain 121 the peak of endoglucanase production was detected in the early stages of colonization (at 33% on WS and at 66% on RG and BS). Laccase activity showed increased values (maxima on WS, 353.68 and 548.67 U g(-1) by strains 121 and 122, respectively) at 66% of colonization. Correlation analysis of growth data demonstrated negative relations between growth rate and biomass yield and between laccase and endoglucanase activities on WS and RG substrates fermented by strain 122. Finally, possible relations of growth parameters with nutritional constituents of the substrates were investigated