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This work shows that ZrO2, used as a modifier of TiO2, can be highly effective as a co-catalyst in the photoelectrocatalytic degradation of dibutyl phthalate (DBP). The monoclinic phase of ZrO2 was easily obtained by chemical deposition on TiO2 nanotubes (Ebg ~3.06 eV), increasing the occurrence of hydroxyl groups and acidity on the surface of the material, as observed by electrophoretic mobility measurements. The optimized photoelectrocatalysis conditions were bias potential of 1.5 V, 0.1 M Na2SO4 (initial pH 6) supporting electrolyte, 6 ppm of DBP, and UV/Vis irradiation. These conditions resulted in complete removal of DBP, down to the limit of detection of the chromatographic method used, with up to complete TOC removal after 60 min of treatment. The effects of pH, bias potential, DBP concentration, and applied potential were investigated. The method was compared with photocatalysis and photolysis. An oxidation mechanism is proposed, based on intermediates detected by LC-MS/MS during 10 min of photoelectrocatalysis. [ABSTRACT FROM AUTHOR]

Current research on the fate and transport of per- and polyfluoroalkyl substances (PFAS) has primarily focused on point-source releases, with less focus on nonpoint-source releases, such as stormwater runoff. In this study, 51 PFAS were investigated in sediment collected from two locations at nine stormwater ponds classified by different land-use types. PFAS concentrations were then related to two different land-use disturbance indicators, the Landscape Development Intensity (LDI) index and the Florida Department of Transportation (FDOT) road type functional classification, to discern a potential metric for estimating PFAS burden by using the proximity to and different types of anthropogenic activity. Of the 51 compounds analyzed, 28 in total were quantified with concentrations ranging from 7.2 to 4,800 ng kg−1. Perfluorinated carboxylic acids were the most commonly identified class of PFAS, as perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUdA), perfluorododecanoic acid (PFDoA), and perfluorotridecanoic acid (PFTrDA) were all found at eight out of nine sites, as well as perfluorooctane sulfonic acid (PFOS), a perfluorinated sulfonic acid. Within the framework of this study, the LDI index did not appear to be significantly correlated to PFAS burden, whereby only the 0.4 km radius of the LDI weighted average resulted in a potential metric for the lowest PFAS contaminated sites (which had correspondingly low LDI weighted means). The FDOT functional classification was a better predictor across all sites for PFAS burden, in which a significant difference was found between the number of PFAS detected at rural and urban sites. Most notably, perfluorohexanoic acid (PFHxA) concentrations were found to be significantly different between rural and urban sites. Moving forward, the potential of utilizing road type functional classification should be explored as a predictive tool to help better prioritize stormwater pond monitoring for PFAS. [ABSTRACT FROM AUTHOR]

Equines are animals widely used in sports events being prone to suffer accidents that can lead to injuries, like trauma in the spine. Horses that suffer from these accidents may have many clinical signs, including neurological, if there is damage to the spinal cord. For the diagnosis of these lesions, techniques as radiography and ultrasonography help in the identification of the severity and location of the damage. In the present report, a female equine, at age 10, was submitted to x-ray exams and diagnosed with cranial cervical dislocation, with fracture and bone fragments dispersed by the musculature. At age 17, it passed by a physical avaliation, which the animal presented pain and sensibility to palpation what extends from the cervical to lumbar and passed by new radiographic exams, indicating the presence of the bone fragments and luxation of C1-C2 articulation. In the treatment, steroidal anti-inflammatory drugs were used associated with the application of platelet-rich autologous plasma at the injury site, a bioproduct rich in platelet growth factors that enhance the body's natural healing process. Resulting in an improvement in the animal's clinical condition. [ABSTRACT FROM AUTHOR]

Pyrethroids, such as cypermethrin (CYP), are widely employed in agriculture, promoting environmental pollution and the need for efficient decontamination methods. In this study, bacteria from orange crops were explored for CYP biodegradation. Among 40 tested bacterial strains, 20 grew in the presence of CYP and 19 performed statistically significant CYP biodegradation in 5 days (20.5%–97.8%). In addition, 3-phenoxybenzoic acid, the main metabolite from CYP, was quantified ranging from 1.1 mg.L−1 to 32.1 mg.L−1. The five most efficient strains, and consortia composed of 5, 10 and 20 bacteria biodegraded the CYP formulation as sole carbon source in phosphate buffer and in minimum mineral medium. Under optimized conditions determined employing Response Surface Methodology, Bacillus sp. CSA-1 and the consortium composed of 10 strains biodegraded 71.0% and 71.6% CYP in 24 h, respectively. Moreover, metabolite identification enabled the proposal of an extended biodegradation pathway with 29 identified compounds, including different new amide and amine derivatives that expanded the knowledge about the fate of this compound in the environment. Experiments of bioaugmentation in soil using Bacillus sp. CSA-1 and the consortium of 10 bacterial strains resulted in faster CYP biodegradation than natural attenuation, showing that the selection of efficient strains for composing a consortium is an interesting approach for bioremediation of pyrethroids. [Display omitted] • From 40 strains, 20 bacteria grew up and 19 biodegraded cypermethrin at 100 mg.L−1. • The consortium of 10 bacteria biodegraded 71% cypermethrin in 24 h in media. • A cypermethrin biodegradation pathway was proposed with 29 identified compounds. • New amide and amine metabolites from cypermethrin were reported. • Bioaugmentation in soil was faster than natural attenuation. [ABSTRACT FROM AUTHOR]

In this study, the degradation of three antibiotics — sulfamethazine (SMT), sulfathiazole (STZ), and norfloxacin (NOR) (1.0 mg L–1 each) — was achieved by coupling the Zero-Valent Iron Process using supported metallic iron nanoparticles (nZVI) to the Fenton one. The system was operated in single-pass continuous-flow mode at steady-state regime (after 15 min). The nanoparticles were packed into a fixed-bed reactor and characterized by several techniques (SEM, EDX, TEM, and XRD). The degradation experiments were performed according to a 22 factorial design, in which the effects of pH and flow rate (Q) were studied. The degradation conditions were: initial pH = 3.0 and Q = 20 mL min–1· H 2 O 2 was then continuously added to the effluent of the nZVI reactor (containing Fe2+) in order to perform the Fenton process in the following mixing vessel (H 2 O 2 concentration of 34 mg L–1). At the exit of the system, the antibiotics concentrations were below the detection limit of the chromatographic method (40 µg L–1) and dissolved iron was below 1.0 mg L–1. Sixteen degradation products (DPs) of SMT, STZ, and NOR were detected and identified using HPLC-MS/MS. Their ecotoxicological endpoints (LC 50 , EC 50 , and ChV) for three trophic levels were estimated with the aid of the ECOSAR 2.0 software. No ecotoxicity was generated towards Lactuca sativa during treatment. The proposed system was able to partially remove the antimicrobial activity (Escherichia coli) of both sulfonamides (16%) and NOR (47%). [Display omitted] • Conditions: C 0 1.0 mg/L, C f 40 μg/L, t 15 min, Q 20 mL/min, pH 3.0, Fe R < 1.0 mg/L. • Several degradation products detected: SMZ − 3; STZ − 5; NOR 8. • SMZ and STZ: more (predicted) ecotoxic products than NOR (aromatic amines). • No ecotoxicity (L. sativa) could be noticed due to the low initial C 0 (1.0 mg/L). • Antimicrobial activity (E. coli) partially removed, better results with NOR. [ABSTRACT FROM AUTHOR]

This work evaluated for the first time the sustainability of vinasse reuse as a fertilizer in sugarcane crops by assessing the occurrence of organic contaminants and their potential for dissemination to soils and groundwater in fertigated areas. A comprehensive screening of organic contaminants was performed in vinasse, soil and groundwater using target analysis, to investigate the occurrence of multiple-class antibiotics, in combination with suspect screening using NORMAN Digital Sample Freezing Platform. Even though antibiotics are used in the ethanol production process and were expected to be ubiquitous contaminants, they were not detected in any of the samples. Nevertheless, the HRMS-based wide-scope suspect screening (including >7800 substances such as pharmaceuticals, agrochemicals, preservatives and industrial chemicals) allowed the tentative identification of 56 compounds, mostly pesticides, food additives, industrial and naturally occurring substances. Results showed no overlap between the compounds detected in vinasse and environmental samples, suggesting that the pollutants found in soil and groundwater might come from alternative sources other than vinasse reuse. Unlabelled Image • The organic contamination potential of vinasse was assessed for the first time. • Antibiotic residues were not found in vinasse, groundwater and soil samples. • The presence of >7500 pollutants was screened for using HRMS-based strategies. • Previously unreported pollutants identified in vinasse, soils and groundwater. • No evidence of soil and groundwater contamination by vinasse was found. [ABSTRACT FROM AUTHOR]

Specific aspects of previously reported extraction workflows, for measurement of per - and polyfluoroalkyl substances (PFAS) in solid matrices, have not been adequately interrogated. The objective of this study was to explore the importance of each workflow step in providing the most appropriate extraction for a comprehensive set of PFAS (51 different species) in soil. We compared different procedures, including two pre-extraction set ups (overnight handling of samples prior to extraction), two extraction solvents (methanol (MeOH), and acetonitrile (ACN)), two extraction solvent volumes (10 mL and 8.5 mL), and two post-extraction cleanup strategies (ENVI-Carb and ion-pair). Of the 51 species targeted, 21 were at quantifiable levels in soil samples collected adjacent to a landfill, of which 13 PFAS were consistently detected among the different extraction workflows. Overall, results showed no significant difference in PFAS concentration between different extraction solvents and cleanup strategies. Perfluoropentanoic acid, perfluorohexanoic acid, and perfluorooctanoic acid had the highest concentrations in all extraction workflows, accounting for nearly 13%, 38%, and 17% of the total monitored PFAS (ΣPFAS), respectively. While final concentration values were similar across methods, recovery and accuracy studies showed that MeOH had the best recovery, with 88% of the isotopically labeled PFAS standards showing extraction recovery within the acceptable range of 80% to 120% (compared to 14% of isotopically labeled PFAS standards in workflows using ACN). Upon examination of additional cleanup steps, 67% of monitored PFAS (out of 51 total PFAS monitored), on average, exhibited higher accuracy (relative error ≤20%) using ENVI-Carb clean up (in comparison with 51% in workflows using ion pair clean up). Results also demonstrated that larger volumes of MeOH (and subsequent re-extractions) did not yield a better recovery, enabling a reduction in overall analysis time and cost in comparison to many published methods. Unlabelled Image • Evaluated different extraction workflows for quantitative analysis of PFAS in soil • Highlighted optimum extraction workflow for PFAS measurement in soil • Quantifiable concentrations of PFAS were present in soil adjacent to a landfill. • PFBA, PFHxA, and PFOA were ubiquitously detected in all soil samples [ABSTRACT FROM AUTHOR]

The pesticides belonging the strobilurin group are among the most common contaminants in the environment. In this work, biodegradation studies of the strobilurin fungicide Pyraclostrobin by bacteria from orange cultivation plots were performed aiming to contribute with the development of a bioremediation method. Experiments were performed in triplicate with validated methods, and optimization was performed by Central Composite Design and Response Surface Methodology. The strains were evaluated in liquid nutrient medium containing 100 mg L−1 of Pyraclostrobin, and decreased concentrations of 61.5 to 100.5 mg L−1 were determined after 5 days at 37 °C and 130 rpm, showing the importance of strain selection. When the five most efficient strains (Bacillus sp. CSA-13, Paenibacillus alvei CBMAI2221, Bacillus sp. CBMAI2222, Bacillus safensis CBMAI2220 and Bacillus aryabhattai CBMAI2223) were used in consortia, synergistic and antagonistic effects were observed accordingly to the employed combination of bacteria, resulting in 64.2 ± 3.9 to 95.4 ± 4.9 mg L−1 residual Pyraclostrobin. In addition, the formation of 1-(4-chlorophenyl)-1 H -pyrazol-3-ol was quantified (0.59–0.01 mg L−1), and a new biodegradation pathway was proposed with 15 identified metabolites. Experiments were also performed in soil under controlled conditions (30 °C, 0–28 days, 100 mg kg−1 pesticide), and the native microbiome reduced the pesticide concentration to 70.4 ± 2.3 mg L−1, whereas the inoculation of an efficient bacterial consortium promoted clearly better results, 57.2 ± 3.9 mg L−1 residual Pyraclostrobin. This suggests that the introduction of these strains in soil in a bioaugmentation process increases decontamination. However, the native microbiome is important for a more efficient bioremediation. Unlabelled Image • Biodegradation of pyraclostrobin by bacteria in growth medium and soil was reported. • New biotransformation pathways were proposed, including 15 intermediate compounds. • Synergistic or antagonistic effects occurred depending of the strains in consortia. • The presence of the soil native microbiome enhanced biodegradation. • The use of efficient strains in soil promoted an increased biodegradation. [ABSTRACT FROM AUTHOR]

The presence of PPCPs (Pharmaceuticals and Personal Care Products) in water sources and drinking water has concerned researchers in recent times. This study was carried out to evaluate the occurrence of 6 PPCPs (namely paracetamol, diclofenac, naproxen, ibuprofen, benzophenone-3 and methylparaben) in the Lobo reservoir, their degradation products, and how efficiently they were removed by 22 ecological filters, considering individual and mixture of compounds. There were 3 spiking events of PPCPs (2 μg L−1) in the ecological filter influents conducted with a lag period of 15 days between spikes. Water samples were collected from the influent and effluent of the filters at 3, 6 and 24 h after each spiking event. All target PPCPs were identified in the Lobo reservoir water in the range of μg L−1. The personal care products were detected with 100% frequency in the samples, and in higher concentrations compared to the pharmaceuticals. Degradation products of diclofenac and benzophenone-3 were identified in the water samples. Results of this investigation show that ecological filtration was an effective process (70–99%) to remove 2 μg L−1 of the selected PPCPs, and demonstrated that the filters were resilient to individual compounds and to their mixtures. Image 1 • Six PPCPs were found in the reservoir water, and personal care products had 100% of frequency. • Two DPs were found in the reservoir water and ecological filter effluents. • Performance of the ecological filters was not affected by PPCP contamination. • 2 μg L−1 of PPCPs were effectively removed by all ecological filters (70–99%). • Results show that filters are resilient to individual PPCP and their mixture. [ABSTRACT FROM AUTHOR]

The combination of chemical analyses and bioassays allows the identification of potentially mutagenic compounds in different types of samples. Dyes can be considered as emergent contaminants and were detected in waters, under the influence of textile activities. The objective of this study was to evaluate the contribution of 9 azo dyes to the mutagenicity of representative environmental samples. Samples were collected along one year in the largest conglomerate of textile industries of Brazil. We analyzed water samples from an important water body, Piracicaba River, upstream and downstream two main discharges, the effluent of a wastewater treatment plant (WWTP) and the tributary Quilombo River, which receives untreated effluent from local industries. Samples were analyzed using a LC-MS/MS and tested for mutagenicity in the Salmonella /microsome microsuspension assay with TA98 and YG1041. Six dyes were detected in the collected samples, Disperse Blue 291, Disperse Blue 373, Disperse Orange 30, Disperse Red 1, Disperse Violet 93, and Disperse Yellow 3. The most sensitive condition for the detection of the mutagenicity was the strain YG1041 with S9. The concentration of dyes and mutagenicity levels varied along time and the dry season represented the worst condition. Disperse Blue 373 and Disperse Violet 93 were the major contributors to the mutagenicity. We conclude that dyes are contributing for the mutagenicity of Piracicaba River water; and both discharges, WWTP effluent and Quilombo River, increase the mutagenicity of Piracicaba River waters in about 10-fold. The combination of chemical analysis and bioassays were key in the identification the main drivers of the water mutagenicity and allows the selection of priority compounds to be included in monitoring programs as well for the enforcing actions required to protect the water quality for multiple uses. [ABSTRACT FROM AUTHOR]

This paper describes the molecular modeling design, synthesis and characterization of a new bio-inspired hexapeptide of acetylcholinesterase enzyme and its interaction with the organophosphate pesticide dichlorvos monitored by UV-Vis spectroscopy and mass spectrometry. This strategy can contribute to the development of synthetic receptors to be coupled to biosensor transducers, avoiding the issues associated with proteins such as low stability under different pH and temperature conditions and high production cost. The resulting data of this work indicate a strong interaction between the pesticide dichlorvos and the hexapeptide (NH3(+)-Glu-His-Gly-Gly-Pro-Ser-COO(-)) with a binding constant of 4.10 × 10(5) M(-1) and the formation of an adduct by covalent binding on the serine residue from the hexapeptide.

In our continuous studies on the chemistry of the endophytic fungus Penicillium griseoroseum, an endophyte isolated from fruits of Coffea arabica, we isolated clavatol, a dimethylated tetraketide, and its dimer which appears to be a novel natural compound. The studies also resulted in the identification of two known tetronic acids, viridicatic acid and terrestric acid, found in ethyl acetate and n-butanol extracts. Spectroscopic studies using 1-D and 2-D NMR and MS/MS analysis were performed to determine the structures of these compounds, first reported by this Penicillium. Two other tetronic acids congeners were identified through HPLC/MS/MS studies, based on fragmentation pattern of ions produced from ionised tetronic acids, and UV light absorptions.

The oxidative potential of the fungus Penicillium brasilianum, a strain isolated as an endophyte from a Meliaceae plant (Melia azedarach), was investigated using 1-indanone as a substrate to track the production of monooxygenases. The fungus produced the dihydrocoumarin from 1-indanone with the classical Baeyer-Villiger reaction regiochemistry, and (-)-(R)-3-hydroxy-1-indanone with 78% ee. Minor compounds resulting from lipase and SAM activities were also detected. The biotransformation procedures were also applied to a collection of Penicillium and Aspergillus fungi obtained from M. azedarach and Murraya paniculata. The results showed that Baeyer-Villiger were mostly active in fungi isolated from M. azedarach. Almost all of the fungi tested produced 3-hydroxy-1-indanone..

The occurrence of 43 pharmaceuticals belonging to predominant therapeutic classes and their distribution in surface water, suspended solids and sediments has been investigated in the Ebro river basin in the Northeast of Spain. WWTP effluents were found to be a main source of contamination and the spatial distribution was affected by the river flow at the sampling point and corresponding dilution factor, resulting in higher concentrations and higher loads in small tributary rivers than in the Ebro river. The study showed that some compounds are preferentially found bound to suspended solids and not detected in river water. Generally, compounds with basic characteristics (pKa > 7) showed higher tendency to bind to suspended solids. The sediment samples generally presented lower concentrations than suspended solids., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Biosynthetic studies on brasiliamides, potently convulsive and bacteriostatic compounds from an endophytic Penicillium brasilianum isolated from Melia azedarach (Meliaceae), confirms their phenylpropanoid origin, which is very uncommon in fungi. Feeding experiments with [2-(13)C]- phenylalanine indicated the incorporation of two units of this amino acid on brasiliamide structures. The first step in the phenylpropanoid pathway to those compounds was evaluated through enzymatic bioassays and confirmed the phenylalanine ammonia-lyase (PAL) participation. The metabolism of phenylalanine in this fungus is discussed.