Degradation of bisphenol A by different fungal laccases and identification of its degradation products

29 p.-5 fig.Different fungal laccases were used as biocatalysts for the biotransformation of bisphenol A (BPA). The quantitative analysis by gas chromatography-mass spectrometry (GCeMS) showed that BPA is more rapidly oxidized by Coriolopsis gallica laccase among the different fungal laccases tested. Carboxylic acid derivatives such as tartaric acid was found as BPA degradation products resulting from reactions catalyzed by 1 U ml 1 of laccase from C. gallica in the presence of 1 mM of the laccase-mediator 1-hydroxybenzotriazole (HBT), while b-hydroxybutyric acid resulted from oxidative reactions without HBT. BPA was completely removed within 3 h and pyroglutamic acid was found as a supplementary oxidative degradation product from HBT when identified by GCeMS. Laccase played a critical role in BPA biodegradation and catalyzed a cross-coupling reactionThis work was supported by the Ministry of Higher Education, Scientific Research (Tunisia) and the Comunidad de Madrid project S2013/MAE-2907Peer reviewe

Phylogenetic and metabolic diversity of Tunisian forest wood-degrading fungi: a wealth of novelties and opportunities for biotechnology

16 p.-2 fig.-5 tab.In this study, 51 fungal strains were isolated from decaying wood samples collected from forests located in the Northwest of Tunisia in the vicinity of Bousalem, Ain Draham and Kef. Phylogenetic analysis based on the sequences of the internal transcribed spacers of the ribosomal DNA showed a high diversity among the 51 fungal isolates collection. Representatives of 25 genera and 29 species were identified, most of which were members of one of the following phyla (Ascomycota, Basidiomycota and Zygomycota). In addition to the phylogenetic diversity, a high diversity of secreted enzyme profiles was also detected among the fungal isolates. All fungal strains produced at least one of the following enzymes: laccase, cellulase, protease and/or lipase.This project received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under Grant Agreement No. 245268 (to L.B.). This study was also supported by the SwissBOL project, financed by the Swiss Federal Office for the Environment (Grant holder L.B.), the Swiss State Secretariat for Education and Research (L.B. Grant Reference: SER No. C09.0139), and the European Union for the COST action FP0801 ‘‘Established and Emerging Phytophthora: Increasing Threats to Woodland and Forest Ecosystems in Europe’’.Peer reviewe

Autochthonous fungal strains with high ligninolytic activities from Tunisian biotopes

6 p.-2 tab.-3 fig.This work represents the first report on the ability of autochthonous fungi of Tunisia to produce ligninolytic enzymes. Three hundred fifteen fungal strains were isolated from different Tunisian biotopes. These fungal strains were first screened for lignin-modifying enzymes on solid media containing Poly R-478 or ABTS. Of the 315 tested strains, 49 exhibited significant ABTS-oxidation activity, expressed within the first week of incubation and only 18 strains decolourised the Poly R-478. These positive strains were further screened in liquid culture and laccase, and lignin and Mn2+-oxidizing peroxidases activities were assayed. Of the 67 strains grown on liquid medium, 28 produced at least one of these 3 enzymes. The 8 highest producers of ligninolytic activities were identified by molecular techniques and 3 among them produced Lac, MnP and LiP simultaneously. New isolates reported in this work as fungi with significant ligninolytic activities includes Oxyporus, Stereum and Trichoderma. The isolated Trametes trogii CTM 10156 was the best Lac producer. Culture conditions and medium composition were optimised for this strain and resulted in high Lac production of 110 U ml-1 within 15 days of incubation (367 times higher than control medium).This research was supported by EU contract N° ICA3-CT-1999-00010 and “Contrats Programmes SERST, Tunisia.Peer reviewe

Autochthonous fungal strains with high ligninolytic activities from Tunisian biotopes

This work represents the first report on the ability of autochthonous fungi of Tunisia to produce ligninolytic enzymes. Three hundred fifteen fungal strains were isolated from different Tunisian biotopes. These fungal strains were first screened for lignin-modifying enzymes on solid media containing Poly R-478 or ABTS. Of the 315 tested strains, 49 exhibited significant ABTS-oxidation activity, expressed within the first week of incubation and only 18 strains decolourised the Poly R-478. These positive strains were further screened in liquid culture and laccase, and lignin and Mn2+-oxidizing peroxidases activities were assayed. Of the 67 strains grown on liquid medium, 28 produced at least one of these 3 enzymes. The 8 highest producers of ligninolytic activities were identified by molecular techniques and 3 among them produced Lac, MnP and LiP simultaneously. New isolates reported in this work as fungi with significant ligninolytic activities includes Oxyporus, Stereum and Trichoderma. The isolated Trametes trogii CTM 10156 was the best Lac producer. Culture conditions and medium composition were optimised for this strain and resulted in high Lac production of 110 U ml-1 within 15 days of incubation (367 times higher than control medium).African Journal of Biotechnology Vol. 4 (5), pp. 431-436, 200

Іван Франко - публіцист

Проаналізовано соціально-економічну і культурно-освітню публіцистику І. Франка, зокрема, його ставлення до податкової політики Австро-Угорщини, діяльності банківської системи, еміграції з Галичини, кооперативного руху, майбутнього української держави.The article analyses social and economic and cultural and educational publications by Ivan Franko, as well as his attitude to tax policies in Austro-Hungarian Empire, banking system activities, emigration from Halychyna, co-operative societies movement, and the future of Ukraine

Modelling of Reactive Black 5 decolourization in the presence of heavy metals by the newly isolated Pseudomonas aeruginosa strain Gb30

Acknowledgements This work was supported by the Ministry of Higher Education and Scientific Research of Tunisia.Peer reviewedPostprin

Влияние автономного инвертора напряжения с синусоидальной широтно-импульсной модуляцией на устойчивость системы электропривода

A method for calculating conditions subharmonic stable AC systems, taking into account the discrete of voltage autonomous inverter with sinusoidal PWM based on which the stable area of AC engine drive

Simultaneous cleanup of Reactive Black 5 and cadmium by a desert soil bacterium

This work was supported by the Ministry of Higher Education and Scientific Research of Tunisia. Special thanks to the Materials Engineering Department of the National School of Engineers of Sfax for help in FTIR spectroscopy analysis and the Digital Research Center of Sfax (CRNS) for support in AFM spectroscopy.Peer reviewedPostprin

An innovative online VFA monitoring system for the anerobic process, based on headspace gas chromatography

A new method for online measurement of volatile fatty acids (VFA) in anerobic digesters has been developed based on headspace gas chromatography (HSGC). The method applies ex situ VFA stripping with variable headspaee volume and gas analysis by gas chromatography-flame ionization detection (GC-FID). In each extraction, digester sample was acidified with H3PO4 and NaHSO4, then heated to strip the VFA into the gas phase. The gas was sampled in a low friction glass syringe before injected into the GC for measurement. The system has been tested for online monitoring of a lab-scale CSTR reactor treating manure for more than 6 months and has shown good agreement with off-line analysis. The system is capable of measuring individual VFA components. This is of advantage since specific VFA components such as propionic and butyric acid can give extra information about the process status. Another important advantage of this sensor is that there is no filtration, which makes possible application in high solids environments. The system can thus be easily applied in a full-scale biogas reactor by connecting the system to the liquid circulation loop to obtain fresh sample from the reactor. Local calibration is needed but automatic calibration is also possible using standard addition method. Sampling duration is 25-40 min, depending on the washing duration, and sensor response is 10 min. This is appropriate for full-scale reactors, since dynamics within most biogas reactors are of the order of several hours. (c) 2006 Wiley Periodicals, Inc