Responses of the Endophytic Bacterial Communities of Juncus acutus to Pollution With Metals, Emerging Organic Pollutants and to Bioaugmentation With Indigenous Strains

Plants and their associated bacteria play a crucial role in constructed wetlands. In this study, the impact of different levels of pollution and bioaugmentation with indigenous strains individually or in consortia was investigated on the composition of the endophytic microbial communities of Juncus acutus. Five treatments were examined and compared in where the wetland plant was exposed to increasing levels of metal pollution (Zn, Ni, Cd) and emerging pollutants (BPA, SMX, CIP), enriched with different combinations of single or mixed endophytic strains. High levels of mixed pollution had a negative effect on alpha diversity indices of the root communities; moreover, the diversity indices were negatively correlated with the increasing metal concentrations. It was demonstrated that the root communities were separated depending on the level of mixed pollution, while the family Sphingomonadaceae exhibited the higher relative abundance within the root endophytic communities from high and low polluted treatments. This study highlights the effects of pollution and inoculation on phytoremediation efficiency based on a better understanding of the plant microbiome community composition

Biodegradation of mixture of plastic films by tailored marine consortia

Summarization: This work sheds light on the physicochemical changes of naturally weathered polymer surfaces along with changes of polymer buoyancy due to biofilm formation and degradation processes. To support the degradation hypothesis, a microcosm experiment was conducted where a mixture of naturally weathered plastic pieces was incubated with an indigenous pelagic community. A series of analyses were employed in order to describe the alteration of the physicochemical characteristics of the polymer (FTIR, SEC and GPC, sinking velocity)as well as the biofilm community (NGS). At the end of phase II, the fraction of double bonds in the surface of microbially treated PE films increased while changes were also observed in the profile of the PS films. The molecular weight of PE pieces increased with incubation time reaching the molecular weight of the virgin pieces (230,000 g mol−1)at month 5 but the buoyancy displayed no difference throughout the experimental period. The number-average molecular weight of PS pieces decreased (33% and 27% in INDG and BIOG treatment respectively), implying chain scission; accelerated (by more than 30%)sinking velocities compared to the initial weathered pieces were also measured for PS films with biofilm on their surface. The orders Rhodobacterales, Oceanospirillales and Burkholderiales dominated the distinct platisphere communities and the genera Bacillus and Pseudonocardia discriminate these assemblages from the planktonic counterpart. The functional analysis predicts overrepresentation of adhesive cells carrying xenobiotic and hydrocarbon degradation genes. Taking these into account, we can suggest that tailored marine consortia have the ability to thrive in the presence of mixtures of plastics and participate in their degradation. Παρουσιάστηκε στο: Journal of Hazardous Material

Sonochemical degradation of triclosan in water and wastewater

The sonochemical degradation of 5 μg l−1 triclosan, a priority micro-pollutant, in various environmental samples (seawater, urban runoff and influent domestic wastewater) as well as in model solutions (pure and saline water) was investigated. Experiments were conducted with a horn-type sonicator operating at 80 kHz frequency and a nominal applied power of 135 W, while solid-phase microextraction coupled with gas chromatography–electron capture detector (SPME/GC–ECD) was employed to monitor triclosan degradation. The latter followed pseudo-first order kinetics with the rate constant being (min−1): 0.2284 for seawater > 0.1051 for 3.5% NaCl in deionised water > 0.0597 for centrifuged urban runoff ∼ 0.0523 for untreated urban runoff > 0.0272 for deionised water > 0.0063 for wastewater influent. SPME/GC–ECD and SPME coupled with gas chromatography–mass spectrometry (SPME/GC–MS) were also used to check for the formation of chlorinated and other toxic by-products; at the conditions in question, the presence of such compounds was not confirmedL.S.-P. and R.B. acknowledge the regional government Junta de Galicia for their doctoral and travel grantsS

Conversion of Uric Acid into Ammonium in Oil-Degrading Marine Microbial Communities: a Possible Role of Halomonads

Uric acid is a promising hydrophobic nitrogen source for biostimulation of microbial activities in oil-impacted marine environments. This study investigated metabolic processes and microbial community changes in a series of microcosms using sediment from the Mediterranean and the Red Sea amended with ammonium and uric acid. Respiration, emulsification, ammonium and protein concentration measurements suggested a rapid production of ammonium from uric acid accompanied by the development of microbial communities containing hydrocarbonoclastic bacteria after 3 weeks of incubation. About 80 % of uric acid was converted to ammonium within the first few days of the experiment. Microbial population dynamics were investigated by Ribosomal Intergenic Spacer Analysis and Illumina sequencing as well as by culture-based techniques. Resulting data indicated that strains related to Halomonas spp. converted uric acid into ammonium, which stimulated growth of microbial consortia dominated by Alcanivorax spp. and Pseudomonas spp. Several strains of Halomonas spp. were isolated on uric acid as the sole carbon source showed location specificity. These results point towards a possible role of halomonads in the conversion of uric acid to ammonium utilized by hydrocarbonoclastic bacteria.With exception of XH and JC, all authors were supported by the FP7 Project ULIXES (FP7-KBBE-2010-266473). This work was further funded by grant BIO2011-25012 from the Spanish Ministry of the Economy and Competitiveness. FM was supported by Università degli Studi di Milano, European Social Fund (FSE) and Regione Lombardia (contract BDote Ricerca^). DD acknowledges support of KAUST, King Abdullah University of Science and Technology. PG acknowledges the support of the European Commission through the project Kill-Spill (FP7, Contract Nr 312139).Peer Reviewe

Microplastics—A New Journal on the Environmental Challenges and Adverse Health Effects of Microplastics

Microplastics is a new, open-access, peer-reviewed journal by MDPI that will provide an advanced forum for scientists to discuss the challenges faced by the ubiquitous presence of microplastics in the environment, as well as their impact on human health and ecosystem services [...

Microplastics generation: Onset of fragmentation of polyethylene films in marine environment mesocosms

open7siFunding by the European Union FP-7 project BIOCLEAN (grant agreement No. 312100) is highly appreciated.The fragmentation of high-density polyethylene (HDPE) films from single-use supermarket plastic bags to microplastics under laboratory-simulated onshore and nearshore conditions was investigated for a period of 6 months. The weathering process of the plastic strips either on beach sand or in seawater under direct natural sunlight was monitored by tensile strength, molecular weight measurements, FTIR, weight loss, and image processing of photographs of the plastic strips before and after mild mechanical stress was applied. The latter represents a novel method proposed for determining the onset of fragmentation through the application of mild mechanical stress on the weathered plastic samples emulating the action of sand and wind on a beach. It was found that 12 h of application of mild mechanical stress in rotating glass bottles filled partially with sand was sufficient time to reach the maximum degree of fragmentation that could occur for the weathered plastics samples being tested. For example, applied mechanical stress yielded an area loss of almost 14% for samples weathered for a period of 5 months and about 16.7% after 5.5 months. While tensile strength tests and molecular weight measurements were rather inconclusive till the very last month when the onset of fragmentation was identified; FTIR measurements revealed that samples under ultraviolet irradiation were gradually modified chemically until fragmentation commenced. After 6 months of weathering, molecular weight measurements showed a 60% reduction for sample SMB-1 whereas for sample SMB-2 the measurement was not possible due to extensive fragmentation. The onset of fragmentation for SMB-1 and SMB-2 samples occurred at a cumulative luminance of 5.3 à 106luxâ¢d and in the presence of atmospheric oxygen whereby the polymer films broke down partially to microplastics. When the UV exposure reached 7.2 à 106luxâ¢d the weathered plastic strips broke down fully to microplastics with the application of a mild mechanical stress. Samples placed in seawater proved to be resistant to fragmentation compared to those on sand over the 6-month period of the weathering experiment. The direct implication of this work is that beached macroplastic debris should be regularly collected from the seashore before they are weathered by sunlight and returned to the sea as microplastics by the action of high waves or strong winds.openKalogerakis, Nicolas*; Karkanorachaki, Katerina; Kalogerakis, G. Calypso; Triantafyllidi, Elisavet I.; Gotsis, Alexandros D.; Partsinevelos, Panagiotis; Fava, FabioKalogerakis, Nicolas*; Karkanorachaki, Katerina; Kalogerakis, G. Calypso; Triantafyllidi, Elisavet I.; Gotsis, Alexandros D.; Partsinevelos, Panagiotis; Fava, Fabi

MADFORWATER. WP2 Adaptation of wastewater treatment technologies for agricultural reuse. Task2.4 Industrial wastewater treatment. Textile wastewater

This data set includes data related to the treatment of textile wastewater (TWW), obtained in the framework of MADFORWATER project. In particular, the data set includes experimental data produced in laboratory relative to the optimization of textile dye decolorization by bacterial consortium. Also, it includes data from experimental observations related to another technology for textile dyes removal: a two-stage (solids separation stage anaerobic/aerobic) moving bed biological bioreactor (MBBR). Three types of potential users are envisaged for this dataset: (i) researchers active in the field of TWW treatment and valorization, that will use these data to design their experiments; (ii) textile industries; (iii) companies active in the fields of wastewater (WW) treatment and valorization