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This study addressed the effectiveness of light emitting diodes to achieve inactivation of three different Aspergillus species (Aspergillus fumigatus, Aspergillus niger and Aspergillus terreus) in a real water matrix. Three single small ultraviolet-C diodes emitting light at two different wavelengths were tested: 255 nm that is similar to the wavelength emitted by low pressure mercury lamps and 265 nm that is closer to the maximum absorbance wavelength of DNA. The ultraviolet-C diodes emitting light at 265 nm were found to be more effective than the 255 nm, achieving 3-log, 1-log and 5-log inactivations of Aspergillus fumigatus, Aspergillus niger and Aspergillus terreus using less than 20 mJ/cm 2 (13,97 mJ/cm 2 ; 7,28 mJ/cm 2 ; 19,74 mJ/cm 2 ). The diodes have also affected the morphology of the fungal spores and increased the percentage of damaged and dead spores., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The presence of mycotoxins in food samples has been widely studied as well as its impact in human health, however, information about its distribution in the environment is scarce. An analytical method comprising a solid phase extraction procedure followed by liquid chromatography tandem mass spectrometry analysis was implemented and validated for the trace analysis of mycotoxins in drinking bottled waters. Limits of quantification achieved for the method were between 0.2ngL(-1) for aflatoxins and ochratoxin, and 2.0ngL(-1) for fumonisins and neosolaniol. The method was applied to real samples. Aflatoxin B2 was the most frequently detected mycotoxin in water samples, with a maximum concentration of 0.48±0.05ngL(-1) followed by aflatoxin B1, aflatoxin G1 and ochratoxin A. The genera Cladosporium, Fusarium and Penicillium were the fungi more frequently detected. These results show that the consumption of these waters does not represent a toxicological risk for an adult., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The effectiveness of free chlorine for the inactivation of fungi present in settled surface water was tested. In addition, free chlorine inactivation rate constants of Cladosporium tenuissimum, Cladosporium cladosporioides, Phoma glomerata, Aspergillus terreus, Aspergillus fumigatus, Penicillium griseofulvum, and Penicillium citrinum that were found to occur in different source waters were determined in different water matrices (laboratory grade water and settled water). The effect of using different disinfectant concentrations (1 and 3 mg/l), temperatures (21 and 4 °C), and pH levels (6 and 7) was addressed. The sensitivity degree of different fungi isolates to chlorine disinfection varied among different genera with some species showing a higher resistance to disinfection and others expected to be more prone to protection from inactivation by the water matrix components. When the disinfection efficiency measured in terms of the chlorine concentration and contact time (Ct) values needed to achieve 99% inactivation were compared with the Ct values reported as being able to achieve the same degree of inactivation of other microorganisms, fungi were found to be more resistant to chlorine inactivation than bacteria and viruses and less resistant than Cryptosporidium oocysts., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A comparison of different isolation techniques and culture media for detection of filamentous fungi and yeasts in the aquatic environment revealed that the use of membrane filtration with the media dichloran rose bengal chloramphenicol (DRBC) optimized fungi detection in terms of abundance and variety in three untreated water sources with very different characteristics (surface water, spring water, and groundwater). The diversity of the fungi population captured by direct DNA extraction of fungi collected by membrane filtration was compared with the isolates obtained after selective growth using different culture media through amplification of the internal transcribed spacer gene and denaturing gradient gel electrophoresis (DGGE). The Czapek-Dox agar, Sabouraud dextrose agar, and DRBC media showed closer similarities to those obtained by the uncultured biomass for the different water sources. Based on these data and the best enumeration results, DRBC is recommended for the assessment of fungi in water sources using culture-based methods. DGGE was also used to monitor temporal variations in the fungal population structure and showed that each water matrix possessed a distinct population profile as well as that changes in the fungal community can be expected in the different matrices throughout the year., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Aims: The main aims of this work were the study of cork slabs moulds colonization and the evaluation of the moulds diversity during cork processing steps, in different cork stoppers factories. Simultaneously, it was envisaged to perform an evaluation of the air quality., Methods and Results: Moulds were isolated and identified from cork slabs and cork samples in four cork stoppers factories. The identification was based on morphological characters and microscopic observation of the reproductive structures. Airborne spore dispersion was assessed using a two stage Andersen sampler. It was observed that Chrysonilia sitophila was always present on cork slabs during the maturing period, but mould diversity appeared to be associated to the different factory configurations and processing steps., Conclusions: Spatial separation of the different steps of the process, including physical separation of the maturation step, is essential to guarantee high air quality and appropriate cork slabs colonization, i.e. C. sitophila dominance. The sorting and cutting of the edges of cork slabs after boiling and before the maturing step is also recommended., Significance and Impact of the Study: This study is very important for the cork stopper industry as it gives clear indications on how to keep high quality manufacturing standards and how to avoid occupational health problems.