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Wang M.,CAS Research Center for Eco Environmental Sciences | Bai Y.,CAS Beijing Institute of Geographic Sciences and Nature Resources Research | Chen W.,CAS Research Center for Eco Environmental Sciences | Markert B.,International Institute of Higher Education, Zittau | And 2 more authors.
Environmental Pollution | Year: 2012

Ecological risks of heavy metals in urban soils were evaluated using Beijing, China as an example. Cadmium, Cu, Zn, Pb, Cr and Ni contents of 233 surface soils sampled by 1 min latitude × 1 min longitude grid were used to identify their spatial distribution patterns and potential emission sources. Throughout the city, longer the duration of urbanization greater was the accumulations of heavy metals especially, Cd, Cu, Pb, and Zn. The soil Zn mainly came from the wears of vehicular tires. Point source emissions of heavy metals were few and far in the downwind south-east quadrant of Beijing. The calculated risk indices showed potential median eco-risks in the ancient central city. No potential high eco-risk due to soil-borne heavy metals was found. The potential medium eco-risk areas in Beijing would expand from the initial 24 to 110 km 2 if soil pH were to reduce by 0.5 units in anticipation. © 2011 Elsevier Ltd. All rights reserved. Source

Wang M.,CAS Research Center for Eco Environmental Sciences | Markert B.,International Institute of Higher Education, Zittau | Chen W.,CAS Research Center for Eco Environmental Sciences | Peng C.,CAS Research Center for Eco Environmental Sciences | Ouyang Z.,CAS Research Center for Eco Environmental Sciences
Environmental Monitoring and Assessment | Year: 2012

In order to evaluate the current state of the environmental quality of soils in Beijing, we investigated contents of 14 metals in Beijing urban soils inside the 5th ring road by even grids sampling. Statistic analyses were conducted to identify possible heavy metal pollutants, as well as the effects of land uses on their accumulation. Our results revealed that the urban soils in Beijing were contaminated by Cd, Pb, Cu, and Zn. Land uses and urbanization ages affected the accumulation of the four heavy metals in soils significantly. Soils in industrial areas have the highest average Cu and Zn contents, while Pb contents in park areas and Cd in agricultural areas are the highest. The accumulations of Pb and Zn in urban soils increase significantly with sampling plots approaching the city center. And Pb, Cd, and Zn contents in soils in traffic areas also tend to increase in the city center. However, residential areas have the lowest contents of all the four heavy metals. © Springer Science+Business Media B.V. 2012. Source

Wang M.,CAS Research Center for Eco Environmental Sciences | Chen W.,CAS Research Center for Eco Environmental Sciences | Markert B.,International Institute of Higher Education, Zittau
Agrochimica | Year: 2010

Fates of chlorimuron-ethyl were investigated in barren soils and farm soils for the purpose of better understanding of its persistence in fields and offering valid parameters for its eco- risk assessment. The degradation of chlorimuron-ethyl occurred mainly by chemical processes and fitted well to the first order kinetic models, with degradation rate constant k of 0.021 ±0.002 and 0.033±0.005, and half lives t1/2 of 32.7 and 21.4 in barren soils and farm soils, respectively, k negatively, while t 1/2 positively correlated with Koc and pH at a significant level of p<0.05. The persistence of chlorimuronethyl was caused by the adsorption to soil organic matter. Source

Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: KBBE.2010.3.3-01 | Award Amount: 4.28M | Year: 2010

Enzymes catalyzing redox reactions (oxidoreductases) represent an environmentally-friendly alternative to harsh chemical reagents in industrial processes that include oxidative transformations for the production of chemicals and other value-added products with large markets in developed and emerging economies. Fungi and other micro-organisms provide the wider and more easily exploitable source for this type of enzymes. However, the penetration of microbial oxidoreductases in the above markets is still low despite the recent discovery of some of the most promising enzymes. Moreover, the use of enzymes as biocatalysts requires tuning their catalytic and operational properties, a type of genetic manipulation that is possible nowadays by the use of protein engineering tools. In the above scenario, the PEROXICATS project focuses first on the search for new peroxidases, one of the most interesting types of oxidoreductases due to their high redox-potential and unique peroxygenase activity recently described in some of them. The huge amount of genomic resources available nowadays, and to be generated during the course of the project, will be exploited in the search for new fungal peroxidase/peroxygenase genes. This will provide a collection of new enzymes to be evaluated in different oxidation reactions that could result in interesting products. On the other hand, some of the main issues presently limiting the industrial application of these enzymes will be addressed, namely their suicide inactivation by peroxide, low functional expression, and limited oxygen transfer potential. Moreover, the catalytic properties of the most interesting enzyme candidates will be modulated to adapt them to the industrial processes. In both cases, a combination of rational and non-rational design will be used, based on directed mutagenesis, and random mutagenesis together with high-throughput screening methods, respectively. In this way, a toolbox of novel and robust peroxidases/peroxygenases will be obtained with high industrial potential. The wide substrate specificity and catalytic plasticity of some peroxidases, which will be further improved within PEROXICATS, make them suitable, for example, to substitute harsh chemicals in the oxidation of recalcitrant compounds or other type of compounds for which a high-redox potential oxidant is required. Peroxygenases have also a great biotechnological potential since they can catalyze selective oxyfunctionalization reactions, among others, required in organic synthesis and difficult to achieve by conventional chemical tools. These characteristics make them of considerable interest in fine chemistry (e.g. substituting costly hydroxylation reactions currently used in the pharmaceutical sector) and bulk chemistry (e.g. for hydrocarbon oxyfunctionalization).

Agency: Cordis | Branch: FP7 | Program: CP-TP | Phase: KBBE.2012.3.5-02 | Award Amount: 3.93M | Year: 2012

In BIOCLEAN project, novel and robust microorganisms (aerobic and anaerobic bacteria, and fungi) able to extensively degrade polyethylene (PE), polypropylene (PP), polystyrol (PS) and polyvinyl chloride (PVC) polymers and plastics will be isolated from actual-site aged plastic wastes obtained from several European marine and terrestrial sites, composting facilities and landfills, and obtained via tailored screenings from existing European collections of microbes. Robust enzymes able to fragment the target plastics with the production of valuable chemicals and building blocks will be obtained from the selected microbes and enzyme collections. Untreated and physically/chemically pre-treated PE, PS, PP and PVC polymers and plastics will be employed in such isolation/ screening activities, and an integrated methodology, relying on advanced analytical methods (determining plastics physicochemical changes and breakdown products resulting from biological attack), and tailored enzymatic, microbiological and ecotoxicological methods, will be adopted for the characterization of actual industrial relevance of the obtained microbes and enzymes. Physical and chemical pretreatments improving biodegradability of target plastics will be identified and transferred on the pilot scale. The most promising microbial cultures and enzymes will be exploited in the development of pilot scale, slurry or solid-phase bioprocesses for the bioremediation and controlled depolymerization, respectively, of target pretreated plastics and in the set up of tailored bioaugmentation protocols for enhancing plastic waste biodegradation in marine water systems, composting and anaerobic digestor facilities. The processes developed will be assessed for their economical and environmental sustainability. Field scale validation of the most promising bioaugmentation protocols in a composting and a marine site and attempts to develop a plastic pollution reduction strategy for the Aegean Sea have been planned too

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