Plant-microorganisms interaction promotes removal of air pollutants in Milan (Italy) urban area.

Plants and phyllosphere microorganisms may effectively contribute to reducing air pollution in cities through the adsorption and biodegradation of pollutants onto leaves. In this work, during all seasons, we sampled atmospheric particulate matter (PM10) and leaves of southern magnolia Magnolia grandiflora and deodar cedar Cedrus deodara, two evergreen plant species widespread in the urban area of Milan where the study was carried out. We then quantified Polycyclic Aromatic Hydrocarbons (PAHs) both in PM10 and on leaves and used sequencing of 16S rRNA gene, shotgun metagenomics and qPCR analyses to investigate the microbial communities hosted by the sampled leaves. Taxonomic and functional profiles of epiphytic bacterial communities differed between host plant species and seasons and the microbial communities on leaves harboured genes involved in the degradation of hydrocarbons. Evidence collected in this work also suggested that the abundance of hydrocarbon-degrading microorganisms on evergreen leaves increased with the concentration of hydrocarbons when atmospheric pollutants were deposited at high concentration on leaves, and that the biodegradation on the phyllosphere can contribute to the removal of PAHs from the urban air.

The Cedrus-associated truffle Trappeindia himalayensis is a morphologically unique and phylogenetically divergent species of Rhizopogon.

In the northwestern Himalayan mountains of India, the hypogeous sequestrate fungus Trappeindia himalayensis is harvested from forests dominated by the ectomycorrhizal tree Cedrus deodara (Himalayan cedar). This truffle has basidiospores that are ornamented with raised reticulation. The original description of Trappeindia himalayensis suggested that the gleba of this species is similar to young specimens of Scleroderma (Boletales), whereas its basidiospores are ornamented with raised reticulation, suggesting a morphological affinity to Leucogaster (Russulales) or Strobilomyces (Boletales). Given this systematic ambiguity, we have generated DNA sequence data from type material and other herbarium specimens and present the first molecular phylogenetic analysis of this unusual Cedrus-associated truffle. Despite the irregular ornamented basidiospore morphology, T. himalayensis is resolved within the genus Rhizopogon (Suillineae, Boletales) and represents a unique lineage that has not been previously detected. All known Rhizopogon species possess an ectomycorrhizal trophic mode, and because of its placement in this lineage, it is likely that Trappeindia himalayensis is an ectomycorrhizal partner of Cedrus deodara. This study highlights the importance of generating sequence data from herbarium specimens in order to identify fungal biodiversity and clarify the systematic relationships of poorly documented fungi.

The effect of environmental contamination on the community structure and fructification of ectomycorrhizal fungi.

Ectomycorrhizal fungi are an essential component of forest ecosystems, most of which can form edible and medical fruiting bodies. Although many studies have focused on the fructification of ectomycorrhizal fungi in phenology, the impact of environmental contamination, especially living garbage, on the formation of fruiting body is still unknown. A field investigation, combined with a high-throughput sequencing method, was used to study the effect of living garbage pollution on the fructification and hypogeous community structure of ectomycorrhizal fungi symbiosing with cedar (Cedrus deodara (Roxb.) G. Don). The results showed that garbage significantly altered soil abiotic and biotic properties, increasing soil urease activity, decreasing the soil exchangeable metal content and phosphatase activity, and ultimately inhibiting the formation of fruiting bodies. The pollution of garbage also changed the community structure of hypogeous ectomycorrhizal fungi where ectomycorrhizal ascomycetes dominated. In unpolluted sites, the relative abundance of ectomycorrhizal ascomycetes and basidiomycetes were almost equal. Although no fruiting bodies were observed in that soil polluted by living garbage, the sequencing result showed that various ectomycorrhizal fungi were present underground, suggesting that these taxonomic fungi had the potential to cope with adverse conditions. This study not only provided a deeper understanding of the relationship between ectomycorrhizal fungal communities and prevailing environmental conditions, but provided a new pathway for the excavation and utilization of the resource of antistress ectomycorrhizal fungi.

A Case of Pulmonary Actinomycosis Associated With Aspiration of Cedar Leaves.

The aspiration of foreign bodies may induce various infectious diseases, including actinomycosis, and its association with foreign bodies has been reported. We encountered a patient who developed Actinomyces-induced lung abscess associated with aspiration of cedar leaves. The patient was a 56-year-old Japanese woman who aspirated decorative cedar leaves contained in a lunch box while eating a meal, and coughing and bloody phlegm occurred thereafter. A mass was noted in the right lower lobe of the lung on plain chest computed tomography on the first consultation, and granules of Actinomyces were noted on transbronchial lung biopsy. Long-term antibiotic administration was performed, but no improvement was obtained. Thus, right lower lobectomy was performed. On postoperative pathologic examination, cedar leaves were present in the bronchus, bacterial colonies adhered to these, and there was surrounding inflammatory cell infiltration, mainly involving histiocytes and lymphocytes. This is the first report of Actinomyces associated with aspiration of cedar leaves. When the foreign body cannot be removed, it may be difficult to improve the condition by antibiotic administration alone, and surgery may be necessary.

Ectomycorrhizal diversity associated with Cedrus deodara and Pinus wallichiana in the Kashmir Himalaya, India.

The present study was undertaken to document the ectomycorrhizal diversity associated with the Cedrus deodara and Pinus wallichiana in the Kashmir Himalaya, India. The extensive field surveys carried out in the Kashmir Himalaya at five study sites resulted in the collection and identification of 76 potential ectomycorrhizal fungal species associated with the Cedrus deodara and Pinus wallichiana. Maximum 32 number of species were found associated with Pinus wallichiana, 19 with Cedrus deodara and 25 species were found growing in association with both the conifers. The present study reveals that Cedrus deodara and Pinus wallichiana in the Kashmir Himalaya, India harbour diverse ectomycorrhizal fungal species.

Experimental and theoretical investigations of the adhesion time of Penicillium spores to cedar wood surface.

In this study, the adhesion of 4 Penicillium strains (Penicillium granulatum, Penicillium crustosum, Penicillium commune and Penicillium chrysogenum) on cedar wood was examined qualitatively and quantitatively by using the extended DLVO (XDLVO) approach and the environmental scanning electronic microscopy (ESEM) technique. A comparison between the XDLVO theories and the ESEM technique was also investigated. The adhesion tests revealed that P. chrysogenum was not able to adhere on the cedar wood substrata, as predicted by the XDLVO approach. We have also found by ESEM that the three Penicillium strains (P. granulatum, P. crustosum, P. commune) adhered on wood, as not predicted theoretically. Moreover, the time of adhesion (3 h and 24 h) was used not only to compare the capacity of adhesion according to contact time but also to explain the discrepancies between the XDLVO approach prediction and the adhesion experiments. A positive relationship between the XDLVO approach and adhesion experiments has been observed after 3h of adhesion. In contrast, a contradiction between the XDLVO predictions and the adhesion test results has been noted after 24h of adhesion of Penicillium strains to the wood surface.

Tubulin inhibitors from an endophytic fungus isolated from Cedrus deodara.

From an endophytic fungus, a close relative of Talaromyces sp., found in association with Cedrus deodara, four compounds including two new ones (2 and 4) were isolated and characterized. The structures of two compounds (1 and 4) were confirmed by X-ray crystallography. The compounds displayed a range of cytotoxicities against human cancer cell lines (HCT-116, A-549, HEP-1, THP-1, and PC-3). All the compounds were found to induce apoptosis in HL-60 cells, as evidenced by fluorescence and scanning electron microscopy studies. Also, the compounds caused significant microtubule inhibition in HL-60 cells.

Environmental Scanning Electron Microscopy characterization of the adhesion of conidia from Penicillium expansum to cedar wood substrata at different pH values.

Initial microbial adhesion to surfaces is a complicated process that is affected by a number of factors. An important property of a solution that may influence adhesion is pH. The surface properties of the cedar wood were characterized by the sessile drop technique. Moreover, the interfacial free energy of surface adhesion to the cedar wood was determined under pH values (2, 3, 5, 7, 9 and 11). The results showed that cedar wood examined at different pH levels could be considered hydrophobic ranged from Giwi = -13.1 mJ/m(2) to Giwi = -75 mJ/m(2). We noted that the electron-donor character of cedar wood was important at both basic and limit acidic conditions (pH 11 and pH 3) and it decreased at intermediate pH (pH 5). The cedar wood substratum presents a weak electron acceptor under various pH's. In addition, the adhesion of conidia from Penicilllium expansum to the cedar wood surfaces at different pH values (2, 3, 5, 7, 9 and 11) was investigated using Environmental Scanning Electron Microscopy and image analysis was assessed with the Mathlab(®) program. The data analysis showed that the conidia from P. expansum were strongly influenced by the pH. The maximum adhesion occurs in the pH 11 and pH 3 and decreased to 24% at pH 5.

Methane fermentation of Japanese cedar wood pretreated with a white rot fungus, Ceriporiopsis subvermispora.

Methane fermentation of Japanese cedar wood was carried out after pretreatment with four strains of white rot fungi, Ceriporiopsis subvermispora ATCC 90467, CZ-3, CBS 347.63 and Pleurocybella porrigens K-2855. These fungi were cultivated on wood chip media with and without wheat bran for 4-8 weeks. The pretreated wood chip was fermented anaerobically with sludge from a sewage treatment plant. Pretreatments with C. subvermispora ATCC 90467, CZ-3 and CBS 347.63 in the presence of wheat bran for 8 weeks decreased 74-76% of beta-O-4 aryl ether linkages in the lignin to accelerate production of methane. After fungal treatments with C. subvermispora ATCC 90467 and subsequent 30-days methane fermentation, the methane yield reached 35 and 25% of the theoretical yield based on the holocellulose contents of the decayed and original wood, respectively. In contrast, treatment with the three strains of C. subvermispora without wheat bran cleaved 15-26% of the linkage and produced 6-9% of methane. There were no significant accelerating effects in wood chips treated with P. porrigens which has a lower ability to decompose the lignin. Thus, it was found that C. subvermispora, with a high ability to decompose aryl ether bonds of lignin, promoted methane fermentation of softwood in the presence of wheat bran.

Fermentability of water-soluble portion to ethanol obtained by supercritical water treatment of lignocellulosics.

The water-soluble (WS) portion obtained by supercritical water treatment of lignocellulosics was studied for its fermentability to ethanol. A fermentation test of the WS portion showed it was not fermented to ethanol. Therefore, a wood charcoal treatment was applied to the WS portion to remove furan and phenolic compounds, which are thought to be the inhibitors to sugar fermentability. It was found that treatment with wood charcoal can be effective at removing these inhibitors and improving the fermentability of the WS portion without reducing the levels of fermentable sugars.

Root system architecture and receptivity to mycorrhizal infection in seedlings of Cedrus atlantica as affected by nitrogen source and concentration.

Effects of nitrogen (N) source and concentration on root system architecture and receptivity to mycorrhizal infection were studied in seedlings of Atlas cedar (Cedrus atlantica Manetti) grown in root observation boxes in a controlled-environment chamber. Nitrogen was supplied in a solution containing either NO3-; or NH4+ at a concentration of either 0.25 or 5.0 mM. Root extension was recorded twice weekly by tracing the roots growing in contact with the transparent face of the root observation box. Among treatments, lateral root production and branching density were greatest with 5.0 mM NO3-. Inoculation with mycelium of Tricholoma cedrorum Malencon was carried out 3 months after the start of the N treatments. The highest percentage of mycorrhizal roots, and the greatest amounts of living mycelium (estimated by the ergosterol assay) were observed in the NO3- treatments. Differences in root branching density among the N treatments were insufficient to explain the observed differences among treatments in the extent of mycorrhizal infection of seedlings.