Use of stable isotope probing to assess the fate of emerging contaminants degraded by white-rot fungus

The widespread of emerging contaminants in the environment and their potential impact on humans is a matter of concern. White-rot fungi are cosmopolitan organisms able to remove a wide range of pharmaceuticals and personal care products (PPCP) through cometabolism (i.e. laccases and peroxidases) or detoxification mechanisms (i.e. cytochrome P450 system). However, the use of PPCP as carbon source for these organisms is largely unexplored. Here, we used carbon stable isotope tracer experiments to assess the fate of anti-inflammatory diclofenac (DCF) and UV filter benzophenone-3 (BP3) during degradation by Trametes versicolor. The comparison between carbon isotopic composition of emitted carbon dioxide from 13C-labelled DCF ([acetophenyl ring-13C6]-DCF) and 13C-BP3 ([phenyl-13C6]-BP3) versus their 12C-homologue compounds showed mineralization of about 45% and 10% of the 13C contained in their respective molecules after 9 days of incubation. The carbon isotopic composition of the bulk biomass and the application of amino acid-stable isotope probing (SIP) allowed distinguishing between incorporation of 13C from BP3 into amino acids, which implies the use of this emerging contaminant as carbon source, and major intracellular accumulation of 13C from DCF without implying the transformation of its labelled phenyl ring into anabolic products. A mass balance of 13C in different compartments over time provided a comprehensive picture of the fate of DCF and BP3 across their different transformation processes. This is the first report assessing biodegradation of PPCP by SIP techniques and the use of emerging contaminants as carbon source for amino acid biosynthesis

C and Cl-CSIA for Elucidating Chlorinated Methanes Biotic and Abiotic Degradation at a Polluted Bedrock Aquifer

AbstractIn this study,concentration and δ13C and δ37Cl values of chloroform (CF) and carbon tetrachloride (CT) measured in groundwater samples are related to redox conditions to elucidate natural attenuation processes in a polluted site. Shifts in δ13C and δ37Cl of CF and CT were detected over time.δ13CCF values found in the potential sources were -34.5 ± 0.6 ‰ (tank near S3 well), -37.3 ± 0.6 ‰ (in a fracture near S1 well) and -46.2± 0.4 ‰ (barrels) in 2004, whereas in later sampling campaigns, δ13CCF enriched values such as -25.2 ± 0.5 ‰ were measured in S3 in 2013. 2D plots (δ13CCFvs δ37ClCF) showed different isotopic patterns in different wells and depths. δ37ClCF values let distinguish that the former sources evolved towards completely different isotopic signatures, whilst δ37ClCF values of +1.3 ± 0.3 ‰ were reached in 2013 for S3,S1 moved towards more depleted δ37ClCF values (down to -3.9 ± 0.6‰). These data indicate that differentreductive dechlorination processes might occur

Evaluation of ethyl tert-butyl ether biodegradation in a contaminated aquifer by compound specific isotope analysis and in situ microcosms

Ethyl tert-butyl ether (ETBE) is an upcoming groundwater pollutant in Europe whose environmental fate has been less investigated thus far. In the present study, we investigated the in situ biodegradation of ETBE in a fuel-contaminated aquifer using compound-specific stable isotope analysis (CSIA) and in situ microcosms in combination with total lipid fatty acid (TLFA)-stable isotope probing (SIP). In a first field investigation, CSIA revealed no significant carbon isotope fractionation but low hydrogen isotope fractionation of up to +14 ¿ along the prevailing anoxic ETBE plume suggesting biodegradation of ETBE. Ten months later, oxygen injection was conducted to enhance the biodegradation of petroleum hydrocarbons (PH) at the field site. Within the framework of this remediation measure, in situ microcosms loaded with [13C6]-ETBE (BACTRAP®s) were exposed for 119 days in selected groundwater wells to assess the biodegradation of ETBE by TLFA-SIP under the following conditions: (i) ETBE as main contaminant; (ii) ETBE as main contaminant subjected to oxygen injection; (iii) ETBE plus other PH; (iv) ETBE plus other PH subjected to oxygen injection. Under all conditions investigated, significant 13C-incorporation into microbial total lipid fatty acids extracted from the in situ microcosms was found, providing clear evidence of ETBE biodegradation

Critical evaluation of the 2D-CSIA scheme for distinguishing fuel oxygenate degradation reaction mechanisms

Although the uniform initial hydroxylation of methyl tert-butyl ether (MTBE) and other oxygenates during aerobic biodegradation has already been proven by molecular tools, variations in carbon and hydrogen enrichment factors (εC and εH) have still been associated with different reaction mechanisms (McKelvie et al. Environ. Sci. Technol. 2009, 43, 2793-2799). Here, we present new laboratory-derived εC and εH data on the initial degradation mechanisms of MTBE, ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) by chemical oxidation (permanganate, Fenton reagents), acid hydrolysis and aerobic bacteria cultures (species of Aquincola, Methylibium, Gordonia, Mycobacterium, Pseudomonas and Rhodococcus). Plotting of Δδ2H/ Δδ13C data from chemical oxidation and hydrolysis of ethers resulted in slopes (Λ values) of 22 ± 4 and between 6 and 12, respectively. With A. tertiaricarbonis L108, R. zopfii IFP 2005 and Gordonia sp. IFP 2009, εC was low (<|-1|¿) and εH insignificant. Fractionation obtained with P. putida GPo1 was similar to acid hydrolysis and M. austroafricanum JOB5 and R. ruber DSM 7511 displayed Λ values previously only ascribed to anaerobic attack. The fractionation patterns rather correlate with the employment of different P450, AlkB and other monooxygenases, likely catalyzing ether hydroxylation via different transition states. Our data questions the value of 2D-CSIA for a simple distinguishing of oxygenate biotransformation mechanisms, therefore caution and complementary tools are needed for proper interpretation of groundwater plumes at field sites

Fem de Consultors!. La geoquímica des d’un punt de vista pràctic.

Projecte: 2017PID-UB039Aquest PMID ha estat dissenyat per a l’assignatura de Mineralogia Ambiental, assignatura optativa de 3 crèdits de 4rt curs del Grau de Geologia, que s’imparteix durant el segon quadrimestre. L’assignatura combina classes magistrals on es promou la interrelació entre conceptes ja explicats en anteriors assignatures i conceptes nous amb classes pràctiques amb ordinadors on s’introdueix als alumnes en l’ús de dos programaris lliures molt utilitzats a nivell professional. Com que durant el mes de maig hi ha moltes sortides i campaments de camp obligatoris, des de la facultat s’ha promogut la compactació del curs, de manera que les classes presencials acaben a finals d’abril, principis de maig. Com a conseqüència, els estudiants tenen pics amb molt volum de feina i no poden assimilar bé els continguts. Aquest PMID està centrat en canviar la metodologia d'una part de les classes per a que l'estudiant assoleixi els coneixements d'una manera més eficaç i efectiva, reduint la seva sensació de sobrecàrrega de treball, sense passar per una reducció dels continguts de l'assignatura. Es proposa la resolució d'un cas concret, com faria en una consultoria del món professional real, combinant aprenentatge col·laboratiu i aula inversa

FEM DE CONSULTORS! La geoquímica des d'un punt de vista pràctic

Es tracta d'un projecte de millora i innovació docent centrat en canviar la metodologia d'una part de les classes per a que l'estudiant assoleixi els coneixements d'una manera més eficaç i efectiva, reduint la seva sensació de sobrecàrrega de treball, sense passar per una reducció dels continguts de l'assignatura. Es proposa la resolució d'un cas concret, com faria en una consultoria del món professional real, combinant aprenentatge col·laboratiu i aula invers

The effect of fibres and carbonation conditions on the mechanical properties and microstructure of lime/flax composites

Fibre and textile-reinforced mortars are increasingly being used for a variety of building applications, including the strengthening of masonry structures. Lime mortars reinforced with sustainable fibres (such as vegetable or cellulosic fibres) may provide an interesting solution. In this paper, a mixture of commercial lime with 20% metakaolin addition was used to produce composites reinforced with non-woven flax fabrics that were cured at different moisture contents (from 0 to 100%) for 7 or 14 days in a CO2 incubator. The composites were char- acterised to determine their flexural behaviour, carbonation level and microstructure. According to the results, no differences exist in the flexural strength of the composites made in the moisture range of 33%–66%. At 7 days of curing, they attained Modulus of Rupture (MOR) values that exceeded 5.5. MPa. Moreover, it was observed that under high moisture conditions, the permeability of the fibres allows for CO2 access, despite the saturation of the pores of the matrix – allowing a reaction in the vicinity of the fibres –, while under dry conditions, the fibre’s moisture retention does not permit the carbonation of the matrix in their vicinity, even though complete carbonation takes place after 14 daysPostprint (published version

Methodology for the evaluation of resilience of ICT systems for smart distribution grids

Ensuring resilient operation and control of smart grids is fundamental for empowering their deployment, but challenging at the same time. Accordingly, this study proposes a novel methodology for evaluating resilience of Information and Communication Technology (ICT) systems for smart distribution grids. Analysing how the system behaves under changing operating conditions a power system perspective allows to understand how resilient the smart distribution grid is, but the resilience of the ICT system in charge of its operation affects the overall performance of the system and does, therefore, condition its resilience. With the aim of systematising the evaluation of ICT systems’ resilience, this study proposes to combine a standardized modelling of Smart Grids, the Smart Grid Architecture Model (SGAM), with a data structured diagram, the Entity Relationship Model (ERM). The architecture of smart distribution grids is analysed through SGAM. Then, their technical characteristics and functionalities are defined and represented in a ERM diagram. Finally, the attributes or properties of the system components are used to formulate resilience indicators against different types of disturbances. This methodology is then applied to analyse the resilience of a ICT platform being developed in EMPOWER H2020 project.Postprint (published version

Cross-validation of methods used for analysis of MTBE and other gasoline components in groundwater.

Head space gas chromatography with flame-ionization detection (HS-GC-FID), ancl purge and trap gas chromatography-mass spectrometry (P&T-GC-MS) have been used to determine methyl-tert-butyl ether (MTBE) and benzene, toluene, and the ylenes (BTEX) in groundwater. In the work discussed in this paper measures of quality, e.g. recovery (94-111%), precision (4.6 - 12.2%), limits of detection (0.3 - 5.7 I~g L 1 for HS and 0.001 I~g L 1 for PT), and robust-ness, for both methods were compared. In addition, for purposes of comparison, groundwater samples from areas suffering from odor problems because of fuel spillage and tank leakage were analyzed by use of both techniques. For high concentration levels there was good correlation between results from both methods

Efficient detection of African Swine Fever Virus using minimal equipment through a LAMP PCR method

African swine fever virus (ASFV) currently represents the biggest threat to the porcine industry worldwide, with high economic impact and severe animal health and welfare concerns. Outbreaks have occurred in Europe and Asia since ASFV was reintroduced into the continent in 2007 and, in 2021, ASFV was detected in the Caribbean, raising alarm about the reemergence of the virus in the Americas. Given the lack of vaccines against ASFV, control of the virus relies on molecular surveillance, which can be delayed due to the need for sample shipment to specialized laboratories. Isothermal PCR techniques, such as LAMP, have become increasingly attractive as point-of-care diagnostic tools given the minimal material expense, equipment, and training required. The present study aimed to develop a LAMP assay for the detection of ASFV. Four LAMP primer sets were designed, based on a consensus sequence for the ASFV p72 gene, and were tested using a synthetic plasmid containing the cloned ASFV p72 target gene as a positive control. Two primer sets, were selected for further validation, given their very short time for amplification. Both primer sets showed thermal stability, amplifying the ASFV DNA at temperatures between 60-70°C and proved to have an analytical limit of detection as low as one ASFV-plasmid DNA copy/µL, using both fluorometric and colorimetric methods. The selected primers did not yield false positive or cross reactive results with other common swine pathogens, showing high specificity. Testing of DNA-spiked samples showed that LAMP amplification was not affected by the nature of the matrices, including oral fluids, tonsils, blood, or rectal swabs. The primer sets were able to detect the two more prevalent ASFV genotypes in the field. Taken together, the results show that ASFV-LAMP-BG2 and ASFV-LAMP-BG3 would be a useful tool for rapid, highly sensitive on-site diagnostic testing