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Bioburden in sleeping environments from Portuguese dwellings
2021
Viegas, Carla | Dias, Marta | Monteiro, Ana | Faria, Tiago | Lage, Joana | Carolino, Elisabete | Caetano, Liliana Aranha | Gomes, Anita Quintal | Almeida, Susana Marta | Verde, Sandra Cabo | Belo, Joana | Canha, Nuno
A wider characterization of indoor air quality during sleep is still lacking in the literature. This study intends to assess bioburden before and after sleeping periods in Portuguese dwellings through active methods (air sampling) coupled with passive methods, such as electrostatic dust cloths (EDC); and investigate associations between before and after sleeping and bioburden. In addition, and driven by the lack of information regarding fungi azole-resistance in Portuguese dwellings, a screening with supplemented media was also performed. The most prevalent genera of airborne bacteria identified in the indoor air of the bedrooms were Micrococcus (41%), Staphylococcus (15%) and Neisseria (9%). The major indoor bacterial species isolated in all ten studied bedrooms were Micrococcus luteus (30%), Staphylococcus aureus (13%) and Micrococcus varians (11%). Our results highlight that our bodies are the source of the majority of the bacteria found in the indoor air of our homes. Regarding air fungal contamination, Chrysosporium spp. presented the highest prevalence both in after the sleeping period (40.8%) and before the sleeping period (28.8%) followed by Penicillium spp. (23.47% morning; 23.6% night) and Chrysonilia spp. (12.4% morning; 20.3% night). Several Aspergillus sections were identified in air and EDC samples. However, none of the fungal species/strains (Aspergillus sections Fumigati, Flavi, Nidulantes and Circumdati) were amplified by qPCR in the analyzed EDC. The correlations observed suggest reduced susceptibility to antifungal drugs of some fungal species found in sleeping environments. Toxigenic fungal species and indicators of harmful fungal contamination were observed in sleeping environments.
Show more [+] Less [-]Preliminary Evaluation of Three Species of Ligninolytic Fungi for Their Possible Incorporation in Vertical Flow Treatment Wetlands for the Treatment of Tequila Vinasse
2021
Ramírez-Ramírez, A. A. | Sulbarán-Rangel, B. C. | Jáuregui-Rincón, J. | Lozano-Álvarez, J. A. | la Torre, J. A Flores-de | Zurita-Martínez, F.
The aim of this study was to evaluate and compare three species of ligninolytic fungi (Trametes versicolor, Bjerkandera adusta, and Phanerochaete chrysosporium) in laboratory-scale columns with respect to their efficiency for the treatment of raw tequila vinasse, in order to assess the feasibility of incorporating this type of fungi in vertical flow treatment wetlands. The following parameters were analyzed at the inlets and outlets of the columns: total suspended solids (TSS), total dissolved solids (TDS), chemical oxygen demand (COD), biological oxygen demand (BOD₅), pH, electrical conductivity (EC), true and apparent color, total nitrogen (TN), nitrites (NO₂⁻), nitrates (NO₃⁻), and total phosphates. The performance of the 3 fungi was very similar (p > 0.05), although T. versicolor showed a trend towards higher efficiencies for the removal of TSS, TN, total phosphates, and COD. The removal efficiencies of TSS were 73.1%, 80.2%, and 78.8% for B. adusta, T. versicolor, and P. Chrysosporium, respectively; for TN removal, the efficiencies were 64.7%, 65.7%, and 60.6%, respectively. The higher removal percentage for COD (10.2%) was obtained in the column with T. versicolor. These results demonstrate the tolerance of the fungi to raw tequila vinasse, their role in reducing pollutant concentrations, and the feasibility of incorporating them into vertical flow treatment wetlands to increase the efficiency of these systems for the treatment of tequila stillage.
Show more [+] Less [-]General assessment of the occurrence of keratinolytic fungi in river and marine beach sediments of catalonian waters (spain)
1997
ULFIG, K. | Guarro, J. | CANO, J. | Gené Badía, Joan | Vidal, P. | Figueras, M. J.
Sediments from 8 river mouths of the Catalonian coast (Spain) were examined for keratinolytic fungi. Out of 1250 river and marine samples examined, 499 (39.9%) were positive for these fungi. Aphanoascus fulvescens (anamorph + teleomorph), Chrysosporium keratinophilum, Ch. tropicum, Ch. an. of Arthroderma curreyi, Ch. pannicola, Ch. europae and Ch. indicum were the predominant species in the sediments. River samples were rich in keratinolytic fungi, whereas in marine beach sediments they occurred sporadically. The results of a preliminary experiment demonstrated that, marine water exerted a dramatical impact on river keratinolytic fungi causing their total or near-total elimination. The qualitative and quantitative compositions of river keratinolytic mycoflora depended on the degree of water contamination with sewage and on natural factors (mainly temperature). The keratinolytic mycoflora of two rivers was possibly altered dramatically by water contaminants, including poisons of industrial origin, and marine salinity. The problem of public health risk resulting from the distribution of keratinolytic fungi within the highly-frequented recreational waters is discussed.
Show more [+] Less [-]Autochthonous Microbiota in Arsenic-Bearing Technosols from Zemianske Kostoľany (Slovakia) and Its Potential for Bioleaching and Biovolatilization of Arsenic
2016
Šimonovičová, Alexandra | Peťková, Katarína | Jurkovič, Ľubomír | Ferianc, Peter | Vojtková, Hana | Remenár, Matej | Kraková, Lucia | Pangallo, Domenico | Hiller, Edgar | Čerňanský, Slavomír
Studied technosols represent a unique system of a 50-year-old environmental burden after dam failure of coal-ash pond. The released ashes rich in arsenic with a thickness of 1–2 m were covered by a 40-cm thick layer of soil. Long-term exposure and selection pressure of elevated concentrations of arsenic (a range of 93–634 μg/g) induced the formation of the specific adapted autochthonous microorganisms. The phylum Proteobacteria was identified as a dominant phylum in the soils and represented only by one class—Gammaproteobacteria with six species. The species of phylum Firmicutes, Bacteroidetes and Actinobacteria were also identified. Thirty-three species of identified autochthonous microscopic fungi belong to 18 genera with the most abundant Mortierella alpina (Zygomycota). The most frequent identified mycobiota belongs to genera Penicillium, Aspergillus, Trichoderma and Alternaria. The isolates of Alternaria triticina, Bionectria ochroleuca, Chrysosporium queenslandicum, Exophiala psychrophila, Metarhizium robertsii, Trichoderma rossicum and Phlebia acerina were identified for the first time in Slovakia. Despite the stimulation of autochthonous community by nutrient medium and augmentation by native species, As leachability was relatively low—on average 5.63 wt.%, 9.23 wt.% and 17.04 wt.% of the total As for inoculated Pseudomonas chlororaphis ZK-1, Pseudomonas putida ZK-5 and Aspergillus niger, respectively. The highest As leachability was achieved through biostimulation of autochthonous microbiota using liquid SAB medium (34.73 wt.% of total As content). Additionally, microbial activity was efficient in the biovolatilization of As from soils (∼70 wt.% of the total As volatilized). It appears that bioremediation using microorganisms represents one of the possible ways of As removal from soils containing coal-combustion ashes with elevated concentrations of As.
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