Impact of a green roof system on indoor fungal aerosol in a primary school in Greece.

A primary school was investigated for airborne fungi by a culture-based method, in classrooms underneath a green roof in comparison to conventional concrete roofs. A portable Burkard sampler was used for the collection of air samples onto petri dishes with 2% Malt Extract Agar. The fungal aerosol mean concentration was 71 CFU m-3 (range 17-176 CFU m-3, median 51) in the classroom directly under the green roof, significantly lower than 192-228 CFU m-3 (range 0-1090 CFU m-3, median 69) under the concrete roofs and 188-412 CFU m-3 (range 0-2183 CFU m-3, median 771) in ground floor classrooms. The Indoor/Outdoor ratio was 0.4 for total fungi and 0.2-1.1 for predominant genera underneath the green roof, whereas 1-2.1 and 0.3-3.2 respectively for the rest of classrooms. The Potential Exposure Dose (PED) for fungal particles was calculated to 4.6 CFU kg-1 and 9.3-35.3 CFU kg-1 respectively. The genera Penicillium, Cladosporium and Aspergillus prevailed indoors and in ambient air. Aspergillus concentrations indoors correlated significantly with the concentration of the coarse fraction (PM10) of particulate matter. The genus Penicillium increased indoors during late spring and summer, in temperature 20-23 °C and relative humidity 42-53% and also predominated in ambient air, both indicative of multiple anthropogenic sources of amplification. The evidence about the green roof positive effect on microbial indoor air quality (mIAQ) is a matter of concern for further investigation.

Bioaccumulation of the artificial Cs-137 and the natural radionuclides Th-234, Ra-226, and K-40 in the fruit bodies of Basidiomycetes in Greece.

The bioaccumulation of artificial Cs-137 and natural radionuclides Th-234, Ra-226, and K-40 by Basidiomycetes of several species is studied and evaluated in relation to their substratum soils. For this reason, 32 fungal samples, representing 30 species of Basidiomycetes, were collected along with their substratum soil samples, from six selected sampling areas in Greece. The fungal fruit bodies and the soil samples were properly treated and the activity concentrations of the studied radionuclides were measured by gamma spectroscopy. The measured radioactivity levels ranged as follows: Cs-137 from <0.1 to 87.2 ± 0.4 Bq kg(-1) fresh weight (F.W.), Th-234 from <0.5 ± 0.9 to 28.3 ± 25.5 Bq kg(-1) F.W., Ra-226 from <0.3 to 1.0 ± 0.5 Bq kg(-1) F.W., and K-40 from 56.4 ± 3.0 to 759.0 ± 28.3 Bq kg(-1) F.W. The analysis of the results supported that the bioaccumulation of the studied natural radionuclides and Cs-137 is dependent on the species and the functional group of the fungi. Fungi were found to accumulate Th-234 and not U-238. What is more, potential bioindicators for each radionuclide among the 32 species studied could be suggested for each habitat, based on their estimated concentration ratios (CRs). The calculation of the CRs' mean values for each radionuclide revealed a rank in decreasing order for all the species studied.

A phylogenetic analysis of Greek isolates of Aspergillus species based on morphology and nuclear and mitochondrial gene sequences.

Aspergillus species originating from Greece were examined by morphological and molecular criteria to explore the diversity of this genus. The phylogenetic relationships of these species were determined using sequences from the ITS and IGS region of the nuclear rRNA gene complex, two nuclear genes ( ß -tubulin (benA) and RNA polymerase II second largest subunit (rpb2)) and two mitochondrial genes (small rRNA subunit (rns) and cytochrome oxidase subunit I (cox1)) and, where available, related sequences from databases. The morphological characters of the anamorphs and teleomorphs, and the single gene phylogenetic trees, differentiated and placed the species examined in the well-supported sections of Aenei, Aspergillus, Bispori, Candidi, Circumdati, Clavati, Cremei, Flavi, Flavipedes, Fumigati, Nidulantes, Nigri, Restricti, Terrei, Usti, and Zonati, with few uncertainties. The combined use of the three commonly employed nuclear genes (benA, rpb2, and ITS), the IGS region, and two less often used mitochondrial gene sequences (rns and cox1) as a single unit resolved several taxonomic ambiguities. A phylogenetic tree was inferred using Neighbour-Joining, Maximum Parsimony, and Bayesian methods. The strains examined formed seven well-supported clades within the genus Aspergillus. Altogether, the concatenated nuclear and mitochondrial sequences offer additional tools for an improved understanding of phylogenetic relationships within this genus.

Malassezia furfur fingerprints as possible markers for human phylogeography.

Malassezia furfur was the first species described within the cosmopolitan yeast genus Malassezia, which now comprises 13 species. Reported isolation rates of these species from healthy and diseased human skin show geographic variations. PCR-fingerprinting with the wild-type phage M13 primer (5'-GAGGGTGGCGGTTCT-3') was applied to investigate phylogeographic associations of M. furfur strains isolated from Scandinavians residing permanently in Greece, in comparison to clinical isolates from Greek, Bulgarian and Chinese native residents. Seven M. furfur strains from Scandinavians were compared with the Neotype strain (CBS1878), CBS global collection strains (n=10) and clinical isolates from Greece (n=4), Bulgaria (n=15) and China (n=6). Scandinavian, Greek and Bulgarian M. furfur strains mostly formed distinct group clusters, providing initial evidence for an association with the host's geographical origin and with the underlying skin condition. These initial data address the hypothesis that M. furfur could be a eukaryotic candidate eligible for phylogeographic studies.