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Assessment and statistical modelling of airborne microorganisms in Madrid
2021
Cordero, José María | Núñez, Andrés | García, Ana M. | Borge, Rafael
The limited evidence available suggests that the interaction between chemical pollutants and biological particles may intensify respiratory diseases caused by air pollution in urban areas. Unlike air pollutants, which are routinely measured, records of biotic component are scarce. While pollen concentrations are daily surveyed in most cities, data related to airborne bacteria or fungi are not usually available. This work presents the first effort to understand atmospheric pollution integrating both biotic and abiotic agents, trying to identify relationships among the Proteobacteria, Actinobacteria and Ascomycota phyla with palynological, meteorological and air quality variables using all biological historical records available in the Madrid Greater Region. The tools employed involve statistical hypothesis contrast tests such as Kruskal-Wallis and machine learning algorithms. A cluster analysis was performed to analyse which abiotic variables were able to separate the biotic variables into groups. Significant relationships were found for temperature and relative humidity. In addition, the relative abundance of the biological phyla studied was affected by PM₁₀ and O₃ ambient concentration. Preliminary Generalized Additive Models (GAMs) to predict the biotic relative abundances based on these atmospheric variables were developed. The results (r = 0.70) were acceptable taking into account the scarcity of the available data. These models can be used as an indication of the biotic composition when no measurements are available. They are also a good starting point to continue working in the development of more accurate models and to investigate causal relationships.
显示更多 [+] 显示较少 [-]Long-term biological monitoring of environmental quality around a solid waste landfill assessed with lichens
2012
Paoli, L. | Corsini, A. | Bigagli, V. | Vannini, J. | Bruscoli, C. | Loppi, S.
The diversity of epiphytic lichens and the accumulation of selected trace elements in the lichen Flavoparmelia caperata L. (Hale) were used as indicators of pollution around a landfill in central Italy along 14 years of waste management. Lichens revealed an increased deposition for some elements (i.e., Cd, Cr, Fe and Ni) and a decrease of the lichen diversity at sites facing the landfill after an enlargement of the dumping area. However, the results allowed to exclude a significant increase in heavy metal depositions in the surrounding area and suggested that successful waste management may be associated with environmental quality. It is concluded that lichen monitoring might provide essential information to enhance the implementation of ecological impact assessment, supporting industrial regulatory procedures, also when waste management is concerned.
显示更多 [+] 显示较少 [-]Exploring the impact of biochar supplement on the dynamics of antibiotic resistant fungi during pig manure composting
2022
Zhou, Yuwen | Zhang, Zengqiang | Awasthi, Mukesh Kumar
The purpose of this study was to investigate antibiotic resistant fungal (ARF) communities in pig manure (PM) composting employing two different biochar (coconut shell-CSB and bamboo biochar-BB) as amendment. Three treatments (Control, 10% CSB and 10% BB) were designed and indicated with T1 to T3. Experimental results declared that the fungal abundance significantly reduced among the both biochar applied treatments but three dominant phyla Ascomycota, Basidiomycota and Mucoromycota were still relatively greater abundance present. There were significant differences (p < 0.05) in the relative abundance and diversity of fungi among all three treatments. Interestingly, biochar addition regulated the overall fungal community in final compost. Compared with the control group, the abundance of fungi was positively mobilized, and especially CSB showed a better effect. Conclusively, biochar has potential to inhibit and reduce the ARGs population and mobility in compost. Thus, these findings offer new insight to understand the succession of ARFs during PM composting.
显示更多 [+] 显示较少 [-]Aerobiological study of bacterial and fungal community composition in the atmosphere of Mexico City throughout an annual cycle
2021
Calderón-Ezquerro, María del Carmen | Serrano-Silva, Nancy | Brunner-Mendoza, Carolina
The atmosphere as a temporary habitat for airborne microbial communities is a valuable topic to explore, and it is through aerobiological studies that the diversity of biological particles and their release, emission, transport, deposition, and impact are assessed. Specific microorganisms are involved in meteorological processes, and phytosanitary and public health concerns. Airborne microbial composition is related to factors such as geographic region and weather conditions.In this study a metagenomic approach was used to determine the composition of bacterial and fungal communities in the air of two different land-use areas (urban area and semi-rural area), during dry and rainy seasons in Mexico City. Air sampling was carried out with a Hirst-type spore trap, collecting the samples simultaneously in both study areas. Forty-two bioaerosol samples were collected, and the DNA obtained was sequenced using Next-Generation Sequencing. The results indicated that the bacterial communities were represented mainly by the phyla Actinobacteria, Proteobacteria, Firmicutes, Bacteroidetes, Cyanobacteria, and the fungal communities by the phyla Ascomycota followed by Basidiomycota. The evident changes in microbial composition were related more to seasonality than to locality, since both UA and SRA showed a high degree of urbanization, despite some differences in land use. Continuous monitoring of atmospheric bioaerosols is essential to determine the influence of meteorological factors on the composition of the aerial microbiota.
显示更多 [+] 显示较少 [-]Assessment of microbial communities in PM1 and PM10 of Urumqi during winter
2016
Gou, Huange | Lu, Jianjiang | Li, Shanman | Tong, Yanbin | Xie, Chunbin | Zheng, Xiaowu
Recently, inhalable particulate matter has been reported to carry microorganisms responsible for human allergy and respiratory disease. The unique geographical environment and adverse weather conditions of Urumqi cause double pollution of dust and smog, but research on the microbial content of the atmosphere has not been commenced. In this study, 16S and 18S rRNA gene sequencing were conducted to investigate the microbial composition of Urumqi's PM1 and PM10 pollutants in winter. Results showed that the bacterial community is mainly composed of Proteobacteria, Firmicutes and Actinobacteria, Proteobacteria accounted for the most proportion which was significant difference in some aforementioned studies. Ascomycota and Basidiomycota constitute the main part of the fungal microbial community. The difference of bacterial relative abundance in sample point is greater than in particle sizes. The sequences of several pathogenic bacteria and opportunistic pathogens were also detected, such as Acinetobacter, Delftia, Serratia, Chryseobacterium, which may impact on immunocompromised populations (elderly, children and postoperative convalescence patients), and some fungal genera may cause several plant diseases. Our findings may serve an important reference value in the global air microbial propagation and air microbial research in desert.
显示更多 [+] 显示较少 [-]Physiological response of the epiphytic lichen Evernia prunastri (L.) Ach. to ecologically relevant nitrogen concentrations
2012
Munzi, S. | Paoli, L. | Fiorini, E. | Loppi, S.
This study investigated the physiological response of the epiphytic lichen Evernia prunastri to ecologically relevant concentrations of nitrogen compounds. Lichen samples were sprayed for 4 weeks either with water or 50, 150 and 500 μM NH₄Cl. The integrity of cell membranes and chlorophyll a fluorescence emission (FV/FM and PIABS) were analyzed. No membrane damage occurred after the exposure period. FV/FM, a classical fluorescence indicator, decreased during the second week of treatment with 500 μM NH₄Cl and the third week with 50 and 150 μM NH₄Cl. PIABS, an overall index of the photosynthetic performance, was more sensitive and decreased already during the first week with 500 μM NH₄Cl and the second week with 150 μM NH₄Cl. Since E. prunastri has been exposed to ammonium loads corresponding to real environmental conditions, these findings open the way to an effective use of this species as early indicators of environmental nitrogen excess.
显示更多 [+] 显示较少 [-]Ozone fumigation (twice ambient) reduces leaf infestation following natural and artificial inoculation by the endophytic fungus Apiognomonia errabunda of adult European beech trees
2010
Olbrich, Maren | Knappe, Claudia | Wenig, Marion | Gerstner, Elke | Häberle, Karl-Heinz | Kitao, Mitsutoshi | Matyssek, Rainer | Stich, Susanne | Leuchner, Michael | Werner, Herbert | Schlink, Katja | Müller-Starck, G (Gerhard) | Welzl, Gerhard | Scherb, Hagen | Ernst, Dieter | Heller, Werner
In 2006, a controlled infection study was performed in the ‘Kranzberger Forst’ to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2× ozone) and three control trees (ambient = 1× ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection. Chronic sublethal ozone exposure reduces both natural and artificial infestation of beech leaves by the endophytic fungus Apiognomonia errabunda.
显示更多 [+] 显示较少 [-]Degradation of oil by fungi isolated from Gulf of Mexico beaches
2015
Simister, R.L. | Poutasse, C.M. | Thurston, A.M. | Reeve, J.L. | Baker, M.C. | White, H.K.
Fungi of the Ascomycota phylum were isolated from oil-soaked sand patties collected from beaches following the Deepwater Horizon oil spill. To examine their ability to degrade oil, fungal isolates were grown on oiled quartz at 20°C, 30°C and 40°C. Consistent trends in oil degradation were not related to fungal species or temperature and all isolates degraded variable quantities of oil (32–65%). Fungal isolates preferentially degraded short (<C18; 90–99%) as opposed to long (C19–C36; 7–87%) chain n-alkanes and straight chain C17- and C18-n-alkanes (91–99%) compared to their branched counterparts, pristane and phytane (70–98%). Polycyclic aromatic hydrocarbon (PAH) compounds were also degraded by the fungal isolates (42–84% total degraded), with a preference for low molecular weight over high molecular weight PAHs. Overall, these findings contribute to our understanding of the capacity of fungi to degrade oil in the coastal marine environment.
显示更多 [+] 显示较少 [-]Fungi and biochar applications in bioremediation of organic micropollutants from aquatic media
2021
Madadi, Rozita | Bester, Kai
The conventional wastewater treatment system such as bacteria, is not able to remove recalcitrant micropollutants effectively. While, fungi have shown high capacity in degradation of recalcitrant compounds. Biochar, on the other hand, has gained attention in water and wastewater treatment as a low cost and sustainable adsorbent. This paper aims to review the recent applications of three major fungal divisions including Basidiomycota, Ascomycota, and Mucoromycotina, in organic micropollutants removal from wastewater. Moreover, it presents an insight into fungal bioreactors, fungal biofilm and immobilization system. Biochar adsorption capacities for organic micropollutants removal under different operating conditions are summarized. Finally, few recommendations for further research are established in the context of the combination of fungal biofilm with the technologies relying on the adsorption by porous carbonaceous materials.
显示更多 [+] 显示较少 [-]Diversity of culturable yeasts associated with zoanthids from Brazilian reef and its relation with anthropogenic disturbance
2017
Paulino, Gustavo Vasconcelos Bastos | Félix, Ciro Ramon | Broetto, Leonardo | Landell, Melissa Fontes
Some of the main threats to coral reefs come from human actions on marine environment, such as tourism, overfishing and pollution from urban development. While several studies have demonstrated an association between bacteria and corals, demonstrating how these communities react to different anthropogenic stressors, yeast communities associated with corals have received far less attention from researchers. The aim of this work was therefore to describe cultivable yeasts associated with three coral species and to evaluate the influence of sewage discharge on yeasts community. We obtained 130 isolates, mostly belonging to phylum Ascomycota and many of them had previously been isolated from human samples or are considered pathogens. The mycobiota was more similar among corals collected from the same reef, indicating that the composition of reef yeast community is more influenced by environmental conditions than host species. We suggest further studies to elucidate which factors are most influential on the composition of the coral-associated yeast community.
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