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Low rank coal- and biomass-derived liquids generally contain a mixture of alkylphenols, which can be dealkylated over zeolites into phenol as a basic chemical. Zeolites with different pore structures were evaluated for the dealkylation of 4-iso-propylphenol as a model alkylphenol, among which HZSM-5 and HMCM-22 displayed the highest phenol selectivity above 96 %. However, HZSM-5 deactivated fastest among the catalysts due to coke deposition. Thus, mesopores were introduced by desilication into HZSM-5 catalysts to improve the catalytic stability. The mesopore incorporation enhanced the connectivity of the micropores with the crystal surface, and shortened the diffusion lengths. Coke location analysis revealed that micropore occlusion by the coke shell occurred on the parent HZSM-5, whereas the acid sites in the desilicated catalysts were more accessible for fully utilization, even though the coke mainly deposited in the micropores. Furthermore, the coke on the desilicated HZSM-5 displayed a lower graphitization degree.

Organic pollutants with high solid-water equilibrium partition coefficients are adsorbed into solid particles and are easily ingested by benthic organisms, potentially causing dietborne toxicity. Whether dietborne toxicity is more important than waterborne toxicity for such chemicals remains to be determined. In this study, we identify the most relevant uptake route for the toxicity of two alkylphenols, 4-tert-butylphenol (4tBP), and 4-tert-octylphenol (4tOP). To achieve this, 6-day toxicity tests under two exposure conditions, namely dietary exposure (clean water + contaminated food) and combined exposure (contaminated water + contaminated food) were conducted on a benthic ostracod, Heterocypris incongruens. The toxicologically important exposure routes were confirmed by the consistency of dietary and aqueous dose-response relationships under different exposure conditions. During the test, frequent renewal of water and food was performed to reduce variability in the exposure conditions. The results showed that, under the equilibrium condition, the dietary exposure route was toxicologically more important than the aqueous route for 4tBP, whereas the waterborne exposure route was more important than the dietary exposure route for 4tOP. This study provides a novel approach to identify the most relevant uptake pathways for chemical toxicity, which better explains the importance of exposure routes in toxicity effects.

Nonylphenol ethoxylate (NPE 10) is a non ionic surfactant which is synthesized from alkylphenol ethoxylate. The accumulation of NPE-10 in wastewater will endanger the ecosystem as well as human being. At present, by an advancement of technology NPE 10 can be degraded indirectly by using an electrochemically treatment. Thus, this study aimed to evaluate the potential electrodegradation of NPE 10 by mediated electrochemical oxidation (MEO) using Ce(IV) ionic mediator. In addition, the influence of Ag(I) ionic catalyst in the performance of MEO for degradation of NPE 10 was also observed. The potency of MEO technology in degradation NPE 10 was evaluated by voltammetry technique and confirmed by titrimetry and LC-MS analyses. The results showed that in the absence of Ag(I) ionic catalyst, the degradation of NPE 10 by MEO was 85.93 %. Furthermore, when the Ag(I) ionic catalyst was applied, the performance of MEO in degradation of NPE 10 was improved to 95.12 %. The back titration using Ba(OH)2 confirmed the formation of CO2 by 46.79 %. Whereas the redox titration shows the total of degradation organic compounds by 42.50 %, which was emphasized by formation of two new peaks in LC-MS chromatogram. In summary, our results confirm the potential of MEO technology for NPE-10 degradation., Comment: 22 pages, 8 figures

Alkyl phenol polyethoxylates (APEOs) are a major group of high production volume chemicals, extensively used as nonionic surfactants in industrial, agricultural and domestic sectors. These surfactants and its respective metabolites are found to be persistent and toxic. Mainly, they act as endocrine disruptors by mimicking the natural hormones. India being a developing country, witnesses pollution due to various industries including tannery. In the present study, sediment samples were collected from the Vellore district of Tamil Nadu, India to investigate the occurrence of APEOs. The sediments were extracted by ultrasonication and analyzed in a liquid chromatography mass spectrometer. Octyl phenol ethoxylates (OPEOs) were not observed in any of the samples. Nonyl phenol ethoxylates (NPEOs) were detected in the range of ND – 36 mg/kg with 85 % detection frequency. The occurrence of NPEOs in sediment indicates its wide usage in tannery and its partitioning behavior in environment. The levels of NPEOs in the study were found to be unsafe according to the sediment guidelines of various studies. Since NPEOs were observed in sediment samples, possibilities of occurrence of their monomers and metabolites cannot be ruled out. Therefore, further studies are warranted for understanding the levels of monomers and metabolites in order to ascertain the environmental risks more appropriately.

Alkylphenols are indispensable chemicals that are currently derived from fossil resources. Conversion of lignin into alkylphenols in a selective manner is highly desirable, while it represents one ...

We analyzed the products of alkylphenol (ortho-, meta-, and para-cresols and 4-isopropylphenol) oxidation by iron(III) chloride in aqueous solutions by HPLC with electrospray ionization and mass-spectrometric detection in the negative ion mode. It was found that the main products formed by the nucleophilic addition of the initial alkylphenols to reactive intermediates, quinone methides. The resulting adducts can be further oxidized, which, after several oxidation–addition cycles, leads to the appearance of a series of compounds with molecular weights belonging to sequences of values of 108, 214, 320, 426, 536, 638, … for cresols and 136, 270, 404, 538, 672, … for 4-isopropylphenol. Such processes are similar to the oxidation of alkylphenols by air oxygen in aqueous solutions and to their electrochemical oxidation yielding dimeric and oligomeric products.

In the present study, 13 endocrine disrupting compounds (EDCs) and their transformation products (TPs) were monitored in Jiulong River and its estuary, China in different seasons. The analytes included antimicrobials [triclosan (TCS) and triclocarbon (TCC)]; estrogens [estrone (E1), estradiol (E2), estriol (E3) and ethinylestradiol (EE2)]; alkylphenol ethoxylates [4-n-nonylphenol (NP) and 4-n-octylphenol (OP)] and the TPs [methyl triclosan (MeTCS), carbanilide (NCC), dichlorocarbanilide, 4-hydroxy estrone (4-OH E1) and 4-hydroxy estradiol (4-OH E2)]. A significant seasonal variation was observed for most EDCs. Approximately, 79% of the total E2 residues were detected in the normal season in comparison with the wet season to indicate recalcitrant behavior of E2 during the normal season. Risk assessment revealed that E2 was most potent among the EDCs to cause highest risk to both vertebrate and invertebrate aquatic species, whereas, E1, EE2, MeTCS and TCS also showed relatively high risk for some surface water aquatic species.

Estrone, 17β-estradiol, 17α-ethynylestradiol, alkylphenols and alkylphenol ethoxylates, are endocrine disruptor compounds. In Portugal, the report of male fish feminization in Minho, Ave and Mondeg...

The effects of different concentrations of oxygen and nitrous oxide on blood gas parameters in pigs maintained under spontaneous or pressure-controlled ventilation, with or without positive end-expiratory pressure (PEEP), were compared. Forty-eight pigs were randomly divided into six groups, submitted to different concentrations of compressed air or N2O, associated with different fractions of inspired oxygen (FiO2). The group subject to 30% of compressed air (GA30) showed the closest proximity to the physiological range of partial pressure (PaO2) expected for the species. For oxygen saturation (SaO2), the values obtained were below the lower physiological limit in the group administered 30% N2O (GN30). Use of PEEP positively interfered in PaCO2 independent of FiO2, however, its effectiveness can be compromised when complemented by N2O-based anesthesia. For SaO2, only GN30 showed values lower than adequate for maintaining tissue oxygenation. The pH, base deficit and bicarbonate in arterial blood were influenced by FiO2 and N2O. In conclusion, the use of compressed air maintains blood gas parameters at their most stable, especially GA30 and PEEP, which seemed to positively influence the experimental groups, with some interference from FiO2 and N2O. RESUMO Compararam-se os efeitos de diferentes concentrações do óxido nitroso ou oxigênio sobre variáveis hemogasométricas, em suínos mantidos em ventilação espontânea ou controlada à pressão, associada ou não à pressão expiratória final positiva (PEEP). Foram utilizados 48 porcos, distribuídos em seis grupos. Administraram-se diferentes concentrações de ar comprimido ou N2O, associadas a diversas frações de oxigênio inspirado (FiO2). O grupo sujeito a 30% de ar comprimido (GA30) mostrou maior proximidade do intervalo fisiológico da pressão parcial de oxigênio (PaO2). Para a saturação de oxigênio (SaO2), observaram-se valores aquém do limite inferior fisiológico no grupo administrado com 30% de N2O (GN30). A utilização da PEEP é capaz de interferir positivamente na PaCO2, independentemente da FiO2, porém tem a efetividade comprometida quando há complemento da anestesia com o N2O. Para a SaO2, apenas o GN30 esboçou valores inferiores aos adequados para manutenção da oxigenação tecidual. O pH, o déficit base e o bicarbonato no sangue arterial foram influenciados pela FiO2 e pelo N2O. Concluiu-se que o uso do ar comprimido mantém os parâmetros hemogasométricos mais estáveis, com destaque para o GA30 e a PEEP, o que parece influenciar positivamente os grupos experimentais, mas com interferência da FiO2 e do N2O.

A novel multi-templates molecularly imprinted polymer (MIP) was prepared on the surface of mesoporous silica coated magnetic graphene oxide (MGO@mSiO2), and applied for the rapid and selective detection of alkylphenol compounds including bisphenol A (BPA), 4-tert-octylphenol (4-tert-OP) and 4-nonylphenol (4-NP) in water. The synthesized composite was characterized by Fourier transform infrared spectrometer, vibrating sample magnetometer, transmission electron microscopy and Brunauer-Emett-Teller surface area analyzer. The MIP showed high adsorption capacity, good selectivity and fast kinetic for these alkylphenols. The maximum adsorption capacities of the MIP for BPA, 4-tert-OP and 4-NP were 16.81, 35.97 and 61.73 mg g−1, respectively, which were significantly higher than those of the non-molecularly imprinted polymer (NIP) due to the imprinting effect. The adsorption of alkylphenols reached equilibrium within 30 min, and followed pseudo-second-order kinetic model and Langmuir model well. The MIP exhibited good sorption selectivity towards BPA, 4-tert-OP and 4-NP, and could be reused 5 times. Furthermore, a new method for ultrasensitive determination of BPA, 4-tert-OP and 4-NP in water by high performance liquid chromatography was developed, using MIP-based magnetic solid-phase extraction coupled with dispersive liquid-liquid microextraction. Under the optimum conditions, the limits of detection (LODs) for BPA, 4-tert-OP and 4-NP were 0.013, 0.010 and 0.010 μg L−1, respectively. The proposed method was used to the detection of BPA, 4-tert-OP and 4-NP in real water samples, with spiked recoveries of 81.5–104.1% and relative standard deviations (RSDs) of 1.0–7.6%, indicating the multi-templates MIP could be a promising adsorbent for separation and analysis of alkylphenols.

Background: Ingestion of house dust has been demonstrated to be an important exposure pathway to several contaminants in young children. These compounds include bisphenol A (BPA), alkylphenols (APs), and alkylphenol ethoxylates (APEOs). Analysis of these compounds in house dust is challenging because of the complex composition of the sample matrix. Objective: The objective was to develop a simple and sensitive method to measure BPA, APs, and APEOs in indoor house dust. Methods: An integrated method that involved solvent extraction using sonication, sample cleanup by solid-phase extraction, derivatization by 2,2,2-trifluoro-N-methyl-N-(trimethylsilyl)acetamide, and analysis by GC coupled with tandem MS was developed for the simultaneous determination of BPA, APs, and APEOs in NIST Standard Reference Material (SRM) 2585 (Organic contaminants in house dust) and in settled house dust samples. Results: Target analytes included BPA, 4-tert-octylphenol (OP), OP monoethoxylate, OP diethoxylate, 4-n-nonylphenol (4nNP), 4nNP monoethoxylate (4nNP1EO), branched nonylphenol (NP), NP monoethoxylate, NP diethoxylate, NP triethoxylate, and NP tetraethoxylate. The method was sensitive, with method detection limits ranging from 0.05 to 5.1 μg/g, and average recoveries between 82 and 115%. All target analytes were detected in SRM 2585 and house dust except 4nNP and 4nNP1EO. Conclusions: The method is simple and fast, with high sensitivity and good reproducibility. It is applicable to the analysis of target analytes in similar matrixes, such as sediments, soil, and biosolids. Highlights: Values measured in SRM 2585 will be useful for future research in method development and method comparison.

The growth and morphology of rumen methanogenic archaea (15 strains of 10 species in 5 genera, including 7 strains newly isolated in the present study) and bacteria (14 species in 12 genera) were investigated using unsupplemented in vitro pure cultures and cultures supplemented with cashew nut shell liquid (CNSL) and its phenolic compound components, anti-methanogenic agents for ruminant animals. Growth of most of the methanogens tested was inhibited by CNSL and alkylphenols at different concentrations ranging from 1.56 to 12.5 mu g/ml. Of the alkylphenols tested, anacardic acid exhibited the most potent growth inhibition. Three gram-negative bacterial species involved in propionate production were resistant to CNSL and alkylphenols (>50 mu g/ml). All the methanogens and bacteria that were sensitive to CNSL and alkylphenols exhibited altered morphology; disruption of the cell surface was notable, possibly due to surfactant activity of the tested materials. Cells division was inhibited in some organisms, with cell elongation and unclear septum formation observed. These results indicate that CNSL and alkylphenols, particularly anacardic acid, inhibit both rumen bacteria and methanogens in a selective manner, which could help mitigate rumen methane generation.

Selective oxidation of C-H bonds in alkylphenols holds great significance for not only structural derivatization in pharma- and bio-manufacturing but also biological degradation of these toxic chemicals in environmental protection. A unique chemomimetic biocatalytic system using enzymes from a p-cresol biodegradation pathway has recently been developed. As the central biocatalyst, the cytochrome P450 monooxygenase CreJ oxidizes diverse p- and m-alkylphenyl phosphates with perfect stereoselectivity at different efficiencies. However, the mechanism of regio- and stereoselectivity of this chemomimetic biocatalytic system remained unclear. Here, using p- and m-ethylphenyl substrates, we elucidate the CreJ-catalyzed key steps for selective oxidations. The crystal structure of CreJ in complex with m-ethylphenyl phosphate was solved and compared with its complex structure with p-ethylphenyl phosphate isomer. The results indicate that the conformational changes of substrate-binding residues are slight, while the substrate promiscuity is achieved mainly by the available space in the catalytic cavity. Moreover, the catalytic preferences of regio- and stereoselective hydroxylation for the two ethylphenyl substrates is explored by molecular dynamics simulations. The ethyl groups in the complexes display different flexibility, and the distances of the active oxygen to Hpro-S and Hpro-R of methylene agree with the experimental stereoselectivity. The regioselectivity can be explained by the distances and bond dissociation energy. These results provide not only the mechanistic insights of CreJ into its regio- and stereoselectivity but also the structural basis for further P450 enzyme design and engineering. Importance The key cytochrome P450 monooxygenase CreJ showed excellent regio- and stereoselectivity in the oxidation of various alkylphenol substrates. C-H bond functionalization of these toxic alkylphenols holds great significance both for biological degradation of these environmental chemicals and production of value-added structural derivatives in pharmaceutical and biochemical industries. Our results, combined with in vitro enzymatic assays, crystal structure determination of enzyme-substrate complex, and molecular dynamics simulations, provide not only significant mechanism elucidation of the regio- and stereoselective catalyzation mediated by CreJ, but also the promising directions for the future engineering efforts of this enzyme towards more useful products. It also has great extendable potentials to couple this multifunctional P450 biocatalyst with other post modifying enzymes (e.g. hydroxyl based glycosylase) to access more alkylphenol derived high-value chemicals through environment-friendly biocatalysis and biotransformation.

Alkylphenols (APs) and short-chain alkylphenol ethoxylates (APEs) containing 1, 2, and 3 ethoxylene units per molecule are known for their endocrine disrupting properties. However, despite bans and restrictions introduced by different countries (the European Union, Canada), APs and their ethoxylates are still widely used on a global scale. In the present chapter, the influence of these compounds on living organisms is presented, and different factors affecting endocrine disrupting properties are discussed, such as length and branching of the alkyl chain, as well as oxidization of both ethoxylene and alkyl chains of APEs molecules. Biodegradation of APs and APEs in both aerobic and anaerobic conditions is also presented, and studies on their bacterial and fungal degradation are discussed. Experiments on removal of these contaminants are described and their environmental fate is shown. Contamination of the environment is discussed separately for water and sediments.

4-tert-Octylphenol (4-tOP) and triclosan (TCS) are endocrine disruptors which have been detected in environmental matrices such as air, soil and water at ultra-low levels. Exposure to endocrine disruptors may account at least in part, for the global increase in the incidence of non-communicable diseases like cancers and diabetes and may also lead to an imbalance in the aquatic ecosystem. River Buffalo is an important natural resource in the Eastern Cape of South Africa serving more than half a million people. The presence of the two compounds in the river water hitherto unknown was investigated during winter seasons using solid-phase extraction and gas chromatography–mass spectrometric techniques. The sampling points differed by some physicochemical parameters. The concentration of 4-tOP ranged 0–755 ng/L, median value 88.1 ng/L while that of TCS ranged 0–1264.2 ng/L and the median value was 82.1 ng/L. Hazard quotient as an index of exposure risk varied according to daphnids ˃ fish ˃ algae for 4-tOP exposure while HQ for TCS exposure was algae > daphnids = fish showing that both compounds were capable of causing imbalance in the aquatic ecosystem.

International audience; Wastewater originating from tank truck cleaning (TTC) industry is reputed for its large variability and may lead to emission of recalcitrant and ecotoxic substances in discharge waters. In this study, TTC wastewater was biologically treated in two lab-scale activated sludge sequencing batch reactors. Two strategies were used, (1) influent pre-treatment with ozone followed by activated sludge treatment and (2) activated sludge treatment followed by polishing with ozone. Effluent soluble chemical oxygen demand (sCOD), ecotoxicity and the 4-nonylphenol (NP) concentration were used to evaluate and compare both strategies. Experiments were conducted for two different TTC companies using the same set-up. For Company 1, a decrease in ecotoxicity of 80 % was observed for algal growth inhibition and 10 % for Daphnia immobilization when using effluent polishing compared to pre-treatment. Hereby the NP concentration decreased below discharge limits (0.3 ng.mL−1). For Company 2 the ecotoxic effect in the algal growth inhibition test increased to 100 % when conducting effluent polishing, while ecotoxicity for the original effluent and the effluent from the pre-treated system were similar. sCOD did not decrease significantly and the discharge limit of NP was only met for one sample. Extended (7 h) effluent ozone polishing tests were conducted at two pH setpoints to assess the impact of radical formation during ozone treatment. In general, it was observed that ozone as a pre-treatment step had no significant influence on ecotoxicity and COD removal. Effluent polishing can improve ecotoxicity and effluent characteristics, despite the dependence on wastewater composition, as toxic side products may be produced.

In the design of highly ordered (covalent organic frameworks) COFs with "ordered domains size and orientation" construction in a well-defined arrangement, the molecular monomers are the key factors. Here, the effect of molecular monomers on the construction of COFs has been studied, and two kinds of molecular monomers, i.e., ethanediamine (flexible amine ligand) and 4,4'-diaminobiphenyl (rigid amine ligand) have been used for developing sheet-like COFs-I and sheet-like COFs-II, respectively. Furthermore, they have been evaluated in the dispersive solid phase extraction (dSPE) procedure for textiles prior to the analysis of alkylphenol by liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS). The results showed that, the optimal usage amount of sheet-like COFs-II used in the dSPE procedure was less than that of sheet-like COFs-I, which may be explained by much higher adsorption capacity of sheet-like COFs via hydrogen-bonding and π-π stacking interactions. Rectilinear calibration graphs were obtained for 4-(tert-octyl)-phenol (4-tOP) and 4-nonylphenol (4-NP) in the range 0.2-20 µg/kg with determination coefficient (r2) higher than 0.9990, and the limits of detection (LODs) of 4-tOP and 4-NP were 0.039 µg/kg and 0.048 µg/kg, respectively. The developed method has been successfully applied to analysis of 50 textile samples, in which 4-tOP and 4-NP were found in six samples with concentrations in the range of 1.6 μg/kg-20.9 μg/kg.

Catechols are antioxidants and radical scavengers with a broad medical potential. 4-Methylcatechol (1b) and 4-ethylcatechol (2b) (occurring in some traditional fermented and smoked foods) activate the cell defense against oxidative stress. We examined the biocatalyzed reactions towards 4-n-alkylcatechols with different side chains length, which is a factor important for the biological activities of catechols. 4-n-Alkylcatechols with methyl through heptyl side chains (1b&ndash, 7b) were obtained in one pot by (i) oxidation of phenols 1a&ndash, 7a with tyrosinase from Agaricus bisporus followed by (ii) reduction of ortho-quinones (intermediates) with L-ascorbic acid sodium salt. The conversions decreased with increasing side chain length. The preparative reactions were carried out with substrates 1a&ndash, 5a. The isolated yields of the purified products decreased from 59% in 2b to 10% in 5b in correlation with logP of the substrates. Homology modeling indicated that the affinities of two tyrosinase isoforms (PPO3 and PPO4) to the substrates with side chains longer than C2 decreased with increasing side chain length. This was probably due to steric limitations and to missing interactions of the extended side chains in the active sites. We envisage using the model to predict further substrates of tyrosinase and testing the products, catechols, for radical-scavenging and biological activities.

A porous water-compatible molecularly imprinted polymer (MIP) coating using catechol as a pseudo-template and a water-soluble functional monomer (4-vinyl benzoic acid) with ethylene glycol dimethacrylate as the crosslinker was developed for extraction of phenols from environmental water samples. The MIP devices were combined with ultra high performance liquid chromatography with a photodiode array detector (UHPLC-PDA) suitable for the simultaneous determination of trace levels of phenolic compounds with a wide range of polarities —phenol, alkylphenols and chlorophenols— in seawater and produced water. Parameters that influence extraction efficiency (salinity, pH, polymer mass, desorption solvent, and desorption time) were optimized to give method detection limits (LOD) ranging from 0.1 to 2 μg L−1 and linearity (R2>0.99) over at least three orders of magnitude for the hydrophobic phenols (e.g., 0.5–1000 μg L−1 for 2,4,6-trichlorophenol) and ~2 orders of magnitude for the light phenols (e.g., 10–120 μg L−1 for phenol, 5–120 μg L−1 for methylphenols and 2-chlorophenol, 0.5–120 μg L−1 3-methyl-4-chlorophenol and 2,4-dichlorophenol). The recoveries from authentic spiked samples ranged from 85 to 100% with %RSDs of 0.2–14% for seawater and 81–107% with %RSD of 0.1–11% for produced water. The resulting MIP-based extraction requires no pre-conditioning of the sorbent, and because the required sample size is small and sample manipulation is limited, the method is easy to multiplex for high throughput sample processing.

Alkylphenol polyethoxylates (APEOn) are the second-largest category of commercial nonionic surfactants, which are difficult to degrade naturally in the environment. This study examined the degradation of octylphenol polyethoxylate (OPEOn) by laccase and its laccase-mediated systems. The results showed that OPEOn was poorly degraded by laccase alone. 2, 2′-azino-bis [3-ethylbenzothiazoline-6-sulphonic acid] (ABTS), 1-hydroxybenzotriazole (HBT), and 2, 2, 6, 6-tetramethylpiperidine-1-oxyl (TEMPO) were selected as the redox mediators. Experimental results also indicated that 52.4% of the initial OPEOn amount was degraded by laccase in the presence of TEMPO. The degradation efficiency was analyzed using high-performance liquid chromatography. Furthermore, the structural characteristics of the degradation products were measured using matrix-assisted laser desorption/ionization-time of flight mass spectrometry and nuclear magnetic resonance spectroscopy, and it could be found that the laccase-TEMPO system could gradually shorten the ethoxylate chain by oxidizing the primary hydroxyl group of OPEOn, thereby degrading the OPEOn of the macromolecule into small molecules. The maximum of the ion peak distributions of OPEOn decreased from n = 8 finally down to 3. The novel enzymatic system introduced by this study will become a promising alternative method for high-efficiency APEOn conversion and had great potential value in wastewater treatment.

Alkylphenols (AP) are widespread environmental compounds belonging to the large family of substances known as Endocrine Disrupting Chemicals (EDCs). The present study was carried out to assess the effects of Octylphenol (OP) alone and in combination with Nonylphenol (NP) on the hypothalamus-pituitary-adrenal gland (HPA) axis of the lizard Podarcis sicula. Lizards are good bioindicators due to their features such as wide distribution, large population and good sensitivity to contaminants. Results obtained showed a time and dose-dependent stimulation of the HPA together with a high variation of both catecholamine plasma levels and greater vascularization and hypertrophy of steroidogenic cord of adrenal gland after both OP and OP + NP treatments. Interestingly, the OP + NP mixture treatment has provoked a state of stress of the adrenal gland which in fact appeared to be characterized by the presence of a marked macrophage infiltration which can be seen especially close to the connective capsule surrounding the gland. This macrophage infiltration could be an evidence of a particularly pronounced inflammatory state to indicate, probably, an animal’s response to a non-physiological situation.

Surfactant can be used to form stable oil-in-water emulsion and reduce the viscosity of viscous crude oil. The mechanism of viscosity reduction was studied for nonionic surfactant alkylphenol polyo...

In this study, a low temperature-curable and alkylphenol ethoxylate-free acrylic emulsion was synthesized with diacetone acrylamide (DAAM) and adipic dihydrazide (ADH) as a crosslinking system; but...

The review substantiates the desirability of developing spent nuclear fuel reprocessing technologies alternative to the Purex process. The practical use of radiochemical technologies based on alkaline and carbonate media, such as extraction of radiocesium from alkaline high-level waste and CARBEX process, is considered. Extraction of actinides with aliphatic amines, β-diketones, phenol derivatives (alkylpyrocatechols, aminomethylphenols, alkylphenol oligomers, calixarenes), and carboxylic acids, as well as extraction in two-phase aqueous systems based on water-soluble polymers, is discussed. The extraction of technetium is considered separately.

The present study reports an ultra high-performance liquid chromatography tandem mass spectrometry method for the simultaneous determination of six bisphenols (bisphenol A, bisphenol B and bisphenol F) and alkylphenols (4-nonylphenol, 4-n-nonylphenol and octylphenol) in hotpot seasoning. Samples were dispersed in n-hexane after addition of internal standards bisphenol A-d4 and 4-n-nonylphenol-d4. Sample solutions were then centrifuged, and the supernatants purified using solid phase extraction with high polarity Carb/PSA composite fillers. Six target analytes were separated on a Waters ACQUITY BEH C18 column by gradient elution with methanol and 0.05% ammonium hydroxide in water as the mobile phase, and determined under multiple reactions monitoring mode. The limits of detection and quantitation, matrix effect, recovery and precision of the method were investigated. Results were linear in the concentration range 0.1–250 µg/L for all compounds of interest, with R2 > 0.9950. Limits of detection were in the range 0.1–0.4 μg/kg, and limits of quantitation were between 0.5 μg/kg and 1.0 μg/kg. The mean recoveries for negative samples at three spiked concentrations were in the range 87.9%–102.4%, and the intra-day precision and inter-day precision were in the ranges 2.1–8.2% and 4.8–11.2%, respectively. This method is accurate and sensitive, and had good clean-up characteristics, which might apply to screening and quantitation of target bisphenols and alkylphenols in hotpot seasoning.

In an aqueous buffer system, serious reverse and side reactions were found in the asymmetric reduction of 2-octanone with Saccharomyces cerevisiae. However, some nonionic surfactants added to the aqueous buffer system improved the bioreduction process by decreasing the reverse and side reaction rates in addition to effectively increasing the average positive reaction rate. Further, a shorter carbon chain length of hydrophilic or hydrophobic moieties in surfactants resulted in a higher yield of (S)-2-octanol. The alkylphenol ethoxylate surfactants had a less influence than polyoxyethylenesorbitan trialiphatic surfactants on the product e.e. It suggested that the product e.e. resulting from the change of carbon chain length of the hydrophobic moieties varied markedly compared with the change of carbon chain length of the hydrophilic moiety. Emulsifier OP-10 and Tween 20 markedly enhanced the yield and product e.e. at the concentration of 0.4 mmol L−1 with a yield of 73.3 and 93.2%, and the product e.e. of 99.2 and 99.3%, respectively, at the reaction time of 96 h.

In this study, we developed a solid state sensor typically used for sensing alkylphenols in an aqueous environment. The colorimetric detection of the analyte is based on Fe(III)-impregnated silica assay with a detection limit that lies in the range of 10−8 mol L−1. The chromic Fe(III)-impregnated silica strip provides an immediate color change signal from yellow to dark purple upon exposure to an aqueous media of an alkylphenol as indicated by the coloration measurements. The visible color change of the thin layer chromatography (TLC) strip was found to change from yellow to dark purple proportionally by increasing the alkylphenol concentration. Recognition of alkylphenol occurs via Fe(III)-phenol complex formation. The energy dispersive spectroscopic analysis was employed to describe the elemental composition of Fe(III)-impregnated silica strip. This Fe(III)-TLC-based platform holds potential for the recognition of different categories of phenols. The proposed assay has the advantage of facile fabrication, portability, easy operation, rapidity, low cost and simplicity over other detection methods, without the need for sophisticated instrumentation and trained personnel. Facile, highly sensitive, fast detection, and portable Fe(III)-impregnated TLC sensor strips for nonylphenol in aqueous media displaying a remarkable visible color change from yellow to dark purple depending on phenol concentration.

Graphene has attracted great interest due to its extensive applications in optoelectronic and electronic circuits and devices. However, reduction of graphene oxide (GO) to graphene is a process in which hydrophilic GO converts to hydrophobic graphene. Very little is known about the aggregation of graphene and the cause of performance degradation by general chemical reduction methods as the single reaction medium presents difficulty in satisfying the good dispersion of hydrophilic GO and hydrophobic graphene simultaneously. In this paper, we report a mixed medium of alkylphenol polyoxyethylene (7) ether (OP-7) and 2-methoxyethanol (EGM) for the preparation of graphene. The strong polar nature of EGM provides a good dispersion environment for GO, while the π–π interaction between the π-electrons in nonionic surfactant OP-7 aromatic ring structure and the π-electrons in graphene make the hydrophobic graphene well dispersed and prevent aggregation. Moreover, the reduction temperature is not high and the reduction time is short. The electrical conductivity of graphene without high-temperature treatment reached 14 000 S m−1. We have found the potential reduction mechanism of graphene and fundamentally solved the problem of aggregation. Our findings make it possible to process graphene materials using low-cost mixed medium processing techniques, providing a valuable reference for the large-scale preparation of graphene.

This review paper summarizes the occurrence, removal and ecological risk of contaminants of emerging concern (CEC) reported in landfill leachate in China since 1996 (43 studies in 10 regions). Results show that many more studies are conducted in developed southeastern China than in developing western and northeastern regions in China. Phthalate esters (PAEs, with 15 studies) and pharmaceuticals and personal care products (PPCPs, with 13 studies) are the two most frequently studied CEC classes. Concentrations of nine CECs classes were in a wide range from 0.03 (organochlorine pesticides) to approximately 4500 μg/L (alkylphenol polyethoxylates/bisphenol analog). Meanwhile, concentrations of CEC compounds range from below detection limit (e.g. doxycycline) to approximately 4500 μg/L (bisphenol A). Several PAEs (diethyl phthalate, di-n-butyl phthalate, and di (2-ethylhexyl) phthalate) and PPCPs (diclofenac and gemfibrizol) have significant variation between sampling sites. Typically, advanced treatment processes can achieve higher removal efficiencies of CEC compounds from landfill leachate compared with conventional treatment processes. Furthermore, environmental risk assessments of CEC compounds in treated landfill leachate using a risk quotient method show that 2 (substituted) polycyclic aromatic hydrocarbons (sPAHs) (benzo(a)anthracene and benzo(b)fluoranthene), 2 PPCPs (bezafibrate and sulfapyridine), γ-hexachlorocyclohexane, and bisphenol A pose high risk. The importance of monitoring and potential risks of CECs in the leachate to vicinity aquatic environment cross China is addressed. Keywords: Contaminants of emerging concern (CEC), Landfill leachate, Occurrence, Temporal/spatial variation, Removal, Environmental risk assessment

Alkoxysilane-functionalized polyethylene can be crosslinked in the presence of acid catalysts, including Bronsted acids, to yield durable pipe and cable insulation materials. However, Bronsted acids can also react with additives present in the formulation such as phenolic antioxidants, resulting in reduced additive efficacy and undesired reaction products. To provide guidelines for the selection of stable phenolic antioxidants in the presence of Bronsted acids, reactions of 4 model alkylphenol compounds in the presence of p-dodecylbenzenesulfonic acid (DBSA) in dodecane were studied as a solution model for polyethylene-based systems. The results point to increasing stability towards DBSA of phenolic compounds when: (i) alkyl groups have less substitution (tertiary carbon compared to quaternary carbon), (ii) they have alkyl-substitution in the para position, and (iii) they have a reduced number of alkyl substituents around the phenol ring. To confirm the trends observed with the model compounds, commercially available antioxidants were also evaluated under the same conditions. Antioxidants with alkyl or isocyanurate bridges had reaction rates comparable to butylated hydroxytoluene (BHT) and followed the trend outlined in model alkylphenols with regards to alkyl group substitution. By comparison, the sulfur-bridged antioxidant stood out as rapidly consumed under the reaction conditions. Therefore, selection of phenolic antioxidants for formulations containing strong Bronsted acids should generally favor phenolic compounds with alkyl-substituted para positions and limited number of alkyl substituents in non-para positions, and without quaternary carbon substituents. Moreover, stability of alternate sulfur-containing antioxidants should be assessed if used with sulfonic acids, given the rapid decomposition of the sulfur-bridged antioxidant observed in this work.

With the continued recovery of heavy oil, conventional polymer flooding cannot be applied to heavy oil reservoirs gradually due to the characteristics of heavy oil reservoirs. To study oil displacement agent suitable for enhanced heavy oil recovery and investigate the effect of EO chain length on the performances, acrylamide, acrylic acid, lauryl methacrylate and C10-C16 alkylphenol ethoxylates were selected to co-polymerize into the active polymer PAAP-x with different EO chain length (14, 16, 18, 20 and 22). Proton nuclear magnetic resonance analysis indicated PAAP-x as the target product. The optimal EO chain length of PAAP-x was determined to be 18 by the analysis of thickening, salt-tolerance, interfacial activity, wettability, viscosity reduction and recovery. Compared with conventional polymer P1, 1500 mg/L PAAP-18 exhibited superior performances with salinity of 6882.2 mg/L: (1) PAAP-18 could maintain the viscosity of 113.1 mPa.s, while P1was 44.8 mPa.s. (2) PAAP-18 could reduce the water-oil IFT from 44.4 mN/m to 13.0 mN/m, while P1 was to 30.6 mN/m, and the water-oil contact angle was 58.2°and 108.5°, respectively. (3) The heavy oil viscosity reduction rate of PAAP-18 was 81.7% at 50 °C, while P1 was only 33.8%. (4) PAAP-18 enhanced heavy oil recovery by 19.85% on the basis of water flooding while conventional polymer was only 8.69%. This study has theoretical guidance and practical significance for the study on new oil displacement agent to enhance heavy oil recovery.

The alkylphenol Mannich bases (N-(4-methylphenyl)-N,N-bis-(3,5-di-tert-butyl-4-hydroxybenzyl)amine, N,N-dibenzyl-N-(3,5-di-tert-butyl-4-hydroxybenzyl)amine and tris-(3,5-di-tert-butyl-4-hydroxybenzyl)amine), which are promising antioxidants for fuels and lubricants, were synthesized by condensation of 2,6-di-tert-Butylphenol with formaldehyde and amines (n-toluidine, dibenzylamine and ammonia). Mannich bases also were synthesized by condensation of alkylphenols with diethylenetriamine. The induction periods of the fuels and lubricants oxidation on the example of the vaseline oil at a temperature of 200 o C were determined by the method of oxygen absorption for the obtained Mannich bases and stable nitroxyl radicals (in particular 2,2,6,6-tetramethyl-4-oxopiperidin-1-oxyl and di-(2,2,6,6-tetramethyl-1-oxyl-4-piperidyl)isophthalate). It was found that in the case of the inhibited oxidation of hydrocarbons of fuels and lubricants, even at high temperatures (~200 o C), there is also a synergetic effect of stable nitroxyl radicals with the nitrogen-containing compounds, including the alkylphenol Mannich bases, which have −NH or β-CH< groups in relation to Nitrogen. So, the obtained results confirm the perspectiveness of the alkylphenol Mannich bases usage as the high-temperature oxidation inhibitors for fuels and lubricants (motor fuels and oils).

In the present study, the levels of alkylphenols (APs) and alkylphenol ethoxylates (APEs) in indoor dust of three different microenvironments were measured and daily intake via dust ingestion estimated. Alkylphenols and alkylphenol ethoxylates were extracted with the aid of sonication and analyzed by gas chromatography mass spectrometry after heptafluorobutyric anhydride derivatization. The concentration values of these pollutants ranged from 1918–10 935 ng g−1; 343–12 438 ng g−1 and 1122–15 324 ng g−1 in dust samples from homes, computer laboratories and offices, respectively. In all the microenvironment studied, di-NPE and mono-NPE were the most abundant isomers suggesting widespread use of NPE-based consumer products in the studied microenvironments. The daily exposure dose (DED) was estimated using min, mean and max concentrations of APs and APEs detected in respected microenvironments. The worst case scenario for the exposure of APEs was highest for toddlers at 146 ng kg−1 bw day−1 followed by teenagers at 11.3 ng kg−1 bw day−1 and adults at daily exposure of 8.53 ng kg−1 bw day−1. Though the daily exposure doses are low, there is a cause for concern as these surfactants are not regulated in many developing countries and their use may be increasing. Keywords: Alkylphenols, Alkylphenol ethoxylates, Concentrations, Indoor dust, Exposure assessment

4-t-Octylphenol (4-t-OP) has become a serious environmental concern due to the endocrine disruption in animals and humans. The biodegradation of 4-t-OP by pure cultures has been extensively investigated only in bacteria and wood-decaying fungi. In this study we isolated and identified 14 filamentous fungal strains from wastewater samples in Taiwan using 4-t-OP as a sole carbon and energy source. The isolates were identified based on sequences from different DNA regions. Of 14 fungal isolates, 10 strains grew effectively on solid medium with a wide variety of endocrine disrupting chemicals as the sole carbon and energy source. As revealed by high-performance liquid chromatography analysis, the most effective 4-t-OP degradation (> 70%) in liquid medium was observed in Fusarium falciforme after 15 days. To our knowledge, this is the first report on the degradation of 4-t-OP as a sole carbon and energy source by non-ligninolytic fungi.

Selective conversion of guaiacol over MoO 3 to produce various alkylphenols, including ethylphenols, isopropylphenols, butylphenols ( tert -, sec -) and tert -amylphenol is investigated in ethanol without the addition of gaseous hydrogen. A high conversion of 99% is achieved at 280 °C for 4 h and the total alkylphenols account for up to 94% in the quantified products. Six molecules, i.e. 2,5-diethylphenol, 2,6-diisopropylphenol, 2,4-diisopropylphenol, 2,6-ditertbutylphenol, 2,4-ditertbutylphenol and 2,6-ditertbutyl-4-ethylphenol, are the main outcomes. The higher alkylphenols in the aforesaid products are verified to form via a novel reaction step in which hydrogen atom at the α-carbon of the lower alkylphenol is substituted consecutively with methyl or ethyl groups. Further examination reveals that catechol is formed as the intermediate via demethylation of guaiacol and followed by direct conversion to low alkylphenols without the formation of phenol. Post-catalytic analysis indicates that an oxycarbohydride phase (MoO x C y H z ) with Mo 5+ developed in the supercritical alcohol batch system played the role of active species. Ethanol is found to be the most effective solvent for the conversion. The MoO 3 catalyst undergoes a gradual deactivation resulted from the consumption of Mo 5+ and carbon deposition but can be regenerated with a simple calcination.

In this study, we describe a high-throughput and sensitive method for textiles analysis, using liquid chromatography coupled to quadrupole-Orbitrap high resolution mass spectrometry (LC-Q-Orbitrap HRMS), for the simultaneously quantitative analysis of 40 target alkylphenol polyethoxylates (APEO) oligomers with reference standards and screening of 160 alcohol polyethoxylates (AEO) oligomers without standards in textiles. The APEOs contain nonylphenol ethoxylates (NPEOs) and octylphenol ethoxylates (OPEOs) with an EO number of ethylene oxide of 1–20, while AEOs focus on C11EOs-C18EOs with an EO number of 1–20. After ultrasonic extraction in methanol, the extract was directly separated using a core-shell CORTECS C18+ column and analyzed by Full MS/dd-MS2 (data dependent acquisition) scan in ESI positive mode. Two best sensitivity experimental conditions for APEOs with short EO chains (AP(EO)1-2) and long EO chains (AP(EO)3-20) were investigated, respectively. Most APEO oligomers had wide concentration ranges and the correlation coefficients (R2) were higher than 0.999. The limit of quantitation (LOQ) values for NP(EO)3-20 oligomers ranges from 16.00 to 52.80 μg/kg and for OP(EO)3-20 oligomers is from 2.40 to 8.00 μg/kg. LOQ for NP(EO)1 and NP(EO)2, OP(EO)1 and OP(EO)2 was 2.40 mg/kg and 0.24 mg/kg, 1.20 mg/kg and 0.16 mg/kg, respectively. The average recovery for each APEO oligomer in cotton and polyester matrix was between 78% and 110% at three spiked levels and the relative standard deviation (RSD%) was below 10%. As to AEOs suspects, a HRMS compound database containing 160 AEO oligomers was built and several parameters such as exact m/z, isotopic patterns, predicted product ions and predicted retention time were used for screening and confirmation. The established method was successfully applied for analysis of 40 commercial textile samples. Compared with OPEOs, NPEOs, especially NP(EO)3-15 oligomers, were widely detected in samples and the total concentration ranged from 1.56 to 1376.31 mg/kg. AEOs were also found in most samples, among which C12-14, C16 and C18 compounds appeared more frequently and the EO chains mainly ranged from 3 to 15.

A practical procedure was developed for detecting nonylphenol ethoxylates (NPEOs) and octylphenol ethoxylates (OPEOs) in household detergents by gas chromatography–mass spectrometry (GC–MS) with the introduction of a cleavage technique using aluminum iodide (AlI3) to convert NPEOs and OPEOs to their parent nonylphenol and octylphenol. The reliability of the cleavage process was evaluated using Igepal-210, Triton X-15, Tergitol NP-9, and Triton X-100 as substrates, demonstrating satisfactory efficiency. The effect of the sample matrix on the cleavage process was investigated, and the optimized dose of AlI3 was estimated. The major advantage of this method is the use of a common analytical tool (GC–MS) for accurate monitoring of APEOs after elimination of the ethoxylate chain, with detection limits of 12.5 mg/kg and 5.0 mg/kg for NPEO9 and OPEO9, respectively. Analytical results revealed that NPEOs and OPEOs were found in 12.6 % of 182 household detergents in the concentration range of 18–800 mg/kg.

Polyether surfactant was employed for the regeneration of a poisoned by calcium V 2 O 5 -WO 3 /TiO 2 catalyst. The OP-10 (alkylphenol polyoxyethylene (10) ether) surfactant exhibited better CaO removal performance than EL-60 (cremophor EL 60) and AEO9 (polyethyleneglycol (9) mono-dodecyl ether). The Ca 2 + -aromatic interactions developed in OP-10 increased the solubility of CaO in water and Ca 2 + could be removed by washing. The high Ca 2 + removal rate by OP-10 surfactant led to the reversible improvement of surface acid sites and active oxygen species. Compared with the traditional method of dilute sulfuric acid solution, the OP-10 presented higher Ca 2 + removal rate with lower V 2 O 5 loss, which is expected to be a facile and environmental benign method for the regeneration of Ca 2 + -poisoned NH 3 -SCR industrial catalysts.

Hydraulic fracturing, coupled with the advances in horizontal drilling, has been used for recovering oil and natural gas from shale formations and has aided in increasing the production of these energy resources. The large volumes of hydraulic fracturing fluids used in this technology contain chemical additives, which may be toxic organics or produce toxic degradation byproducts. This paper investigated the chemicals introduced into the hydraulic fracturing fluids for completed wells located in Pennsylvania and West Virginia from data provided by the well operators. The results showed a total of 5071 wells, with average water volumes of 5,383,743 ± 2,789,077 gal (mean ± standard deviation). A total of 517 chemicals was introduced into the formulated hydraulic fracturing fluids. Of the 517 chemicals listed by the operators, 96 were inorganic compounds, 358 chemicals were organic species, and the remaining 63 cannot be identified. Many toxic organics were used in the hydraulic fracturing fluids. Some of them are carcinogenic, including formaldehyde, naphthalene, and acrylamide. The degradation of alkylphenol ethoxylates would produce more toxic, persistent, and estrogenic intermediates. Acrylamide monomer as a primary degradation intermediate of polyacrylamides is carcinogenic. Most of the chemicals appearing in the hydraulic fracturing fluids can be removed when adopting the appropriate treatments.

Sulfur-, nitrogen-, and boron-modified alkylphenol additives for motor oils have been first produced by condensation of sulfurized alkylphenols with formaldehyde, alkanolamines, and boric acid followed by neutralization of the condensation products with calcium hydroxide. The structure of the resulting additives has been confirmed by IR spectroscopy. The functional properties of the additives in the composition of motor oils have been investigated. It has been found that they have high corrosion-preventing, antioxidant, and tribological properties and can be used as an additive for various motor oils. A lubricant composition M-14G2 with high performance characteristics meeting the requirements of modern technology has been developed with the use of the additive IKhP-228.

A pH-sensitive polymer based on the poly(styrene- alt -maleic anhydride) co-polymer serves as basis to develop a microextraction method (pH-HGME) in direct combination with high-performance liquid chromatography (HPLC) and fluorescence detection (FD) for the determination of seven organic com- pounds, including three polycyclic aromatic hydrocarbons (PAHs), three monohydroxylated PAHs and one alkylphenol, in urine. The method bases on the structural modification of the pH-sensitive polymer in the aqueous sample at a high pH value, followed by the formation and insolubilization of a hydrogel contain- ing the preconcentrated analytes by decreasing the pH, and the direct injection of the hydrogel-rich phase in the HPLC-FD system. The optimization of the main variables permitted the selection of low amounts of aqueous sample (10 mL), which was mixed with 10 mg of co-polymer also present in a low volume (150 μL) of concentrated NaOH. The method further requires the addition of 200 μL of concentrated HCl, 3 min of stirring, and 15 min of centrifugation. This pH-HGME-HPLC-FD method presented low limits of detection, ranging from 0.001 μg L −1 to 0.09 μg L −1 in ultrapure water, average relative recoveries of 96.9% for the concentration level of 0.60 μg L −1 , and enrichment factors between 1.50 and 17.7. The pro- posed method also exhibited high precision, with intermediate relative standard deviations lower than 16% for a concentration level of 0.60 μg L −1 . The developed pH-HGME-HPLC-FD method performed ade- quately when analyzing two human urine samples provided by a non-smoker male and a smoker female, respectively. One of the target analytes (2-hydroxynaphthalene) was quantified in both samples using the standard addition method, with a predicted concentration of 7.3 ±0.4 μg L −1 in the non-smoker male urine and 19.3 ±0.6 μg L −1 in the smoker female urine. Agencia Canaria de Investigación, Innovación y Sociedad de la Información University of Regensburg Ministerio de Ciencia, Innovación y Universidades Ministerio de Economía, Industria y Competitividad

The bacterial catabolism of aromatic compounds has considerable promise to convert lignin depolymerization products to commercial chemicals. Alkylphenols are a key class of depolymerization products whose catabolism is not well elucidated. We isolatedRhodococcus rhodochrousEP4 on 4-ethylphenol and applied genomic and transcriptomic approaches to elucidate alkylphenol catabolism in EP4 andRhodococcus jostiiRHA1. RNA-Seq and RT-qPCR revealed a pathway encoded by theaphABCDEFGHIQRSgenes that degrades 4-ethylphenol via themeta-cleavage of 4-ethylcatechol. This process was initiated by a two-component alkylphenol hydroxylase, encoded by theaphABgenes, which were up-regulated ~3,000-fold. Purified AphAB from EP4 had highest specific activity for 4-ethylphenol and 4-propylphenol (~2000 U/mg) but did not detectably transform phenol. Nevertheless, a ΔaphAmutant in RHA1 grew on 4-ethylphenol by compensatory up-regulation of phenol hydroxylase genes (pheA1-3). Deletion ofaphC, encoding an extradiol dioxygenase, prevented growth on 4-alkylphenols but not phenol. Disruption ofpcaLin the β-ketoadipate pathway prevented growth on phenol but not 4-alkylphenols. Thus, 4-ethylphenol and 4-propylphenol are catabolized exclusively viameta-cleavage in rhodococci while phenol is subject toortho-cleavage. Putative genomic islands encodingaphgeneswere identified in EP4 and several other rhodococci. Overall, this study identifies a 4-alkylphenol pathway in rhodococci, demonstrates key enzymes involved, and presents evidence that the pathway is encoded in a genomic island. These advances are of particular importance for wide-ranging industrial applications of rhodococci, including upgrading of lignocellulose biomass.ImportanceElucidation of bacterial alkylphenol catabolism is important for the development of biotechnologies to upgrade the lignin component of plant biomass. We isolated a new strain,Rhodococcus rhodochrousEP4, on 4-ethylphenol, an alkylphenol that occurs in lignin-derived streams, including reductive catalytic fractionation products of corn stover. We further demonstrated its degradation via ameta-cleavage pathway (Aph) with transcriptomics. A new class of Actinobacterial hydroxylase, AphAB, acts specifically on alkylphenols. Phylogenomic analysis indicated that theaphgenes occur on putative genomic islands in several rhodococcal strains. These genes were identified in the genetically-tractable strainRhodococcus jostiiRHA1. Strains missing this element cannot metabolise 4-ethylphenol and 4-propylphenol. Overall, we advanced the understanding of how aromatic compounds are degraded by environmental bacteria and identified enzymes that can be employed in the transition away from petro-chemicals towards renewable alternatives.

A fast methodology to quantify 4-tert-octylphenol (4-t-OP) and 4-nonylphenol (4-NP) and their mono- and di-ethoxylates was developed, validated, and applied to real wastewater samples. Dispersive liquid-liquid microextraction was employed as a sample preparation step, leading to a pre-concentration factor of roughly 30. Analysis was carried out by liquid chromatography-tandem mass spectrometry with electrospray ionisation in multiple reaction monitoring mode. Average recoveries were generally between 80 and 120% for both the alkylphenols and their mono- and di-ethoxylates in influent and effluent wastewater. A minimum of 5 concentration levels per compound, ranging between 1 and 500 ng/mL, were prepared to construct calibration curves making use of isotopically labelled internal standards. The method presented good linearity and repeatability over the whole range of concentrations. Taking into account the concentration factor, and the recovery of the compounds, lower limits of quantification obtained in effluent wastewater were 0.04 ng/mL for 4-t-OP and 0.14 ng/mL for 4-NP, complying with European regulations, and between 0.03 ng/mL and 0.39 ng/mL for the ethoxylates. In influent wastewater, these limits were slightly higher. The total run time of 5 min for the alkylphenols and 8 min for the ethoxylates ensured high throughput. The developed method was applied to determine 4-t-OP and 4-NP and their mono- and di-ethoxylates in wastewater from several tank truck cleaning companies, which was subjected to ozonation and/or biological treatment. It was demonstrated that ozonation was best applied after the biological treatment, since in this case, the biological treatment could degrade most of the biodegradable organic matter, after which ozone could react directly with the recalcitrant organic pollutants. In this case, the concentrations of the target compounds in the wastewater of the investigated company decreased below the legally allowed concentration of the European water legislation. ispartof: ANALYTICAL AND BIOANALYTICAL CHEMISTRY vol:411 issue:8 pages:1611-1621 ispartof: location:Germany status: published

A new metal-free reductive amination protocol using a pinacol-derived chlorohydrosilane/pyridine system for the preparation of aminoalkylphenols is described. This method is selective toward iminiums derived from alkylphenol ketones under an in situ formation of a trialkoxyhydrosilane and activation with a Lewis base, as further indicated by computational studies. This method demonstrated high functional group tolerance affording an array of novel aminoalkylphenols in moderate to high yields with equimolar amounts of reactants and a wide substrate scope. publishedVersion

Anthropogenic surface and ground water contamination by chemicals is a global problem, and there is an urgent need to develop tools to identify and elucidate biological effects. Contaminants of emerging concern (CECs) are not typically monitored or regulated and those with known or suspected endocrine disrupting potential have been termed endocrine disrupting chemicals (EDCs). Many CECs are known to be neurotoxic (e.g., insecticides) and many are incompletely characterized. Behavioral responses can identify chemicals with neuroactive properties, which can be relevant to EDC mechanisms (e.g., neuroendocrine disturbances). Two freshwater species, Daphnia pulex and Danio rerio, were evaluated for swimming behavior alterations resulting from 24-hr exposure to 9 CECs: triclosan, triclocarban, chlorpyrifos, dieldrin, 4-nonylphenol, bisphenol-A, atrazine, metformin, and estrone. This is the first step in the development of a bioassay for detecting estrogenic and/or anti-androgenic activity with the goal to evaluate complex mixtures of uncharacterized contaminants in water samples. The second step, described in a subsequent report, examines transcriptome alterations following chemical exposure. Significant differences in the swimming behavior response and sensitivity were found across chemicals within a species and across species for a given chemical in this unique optical bioassay system. In the concentration ranges studied, significant behavioral alterations were detected for 6 of 9 CECs for D. pulex and 4 of 9 CECs for D. rerio. These results underscore the utility of this bioassay to identify behavioral effects of sublethal concentrations of CECs before exploration of transcriptomic alterations for EDC detection.

In this study, the ability of laccase Gl-LAC-4, purified from Ganoderma lucidum, to degrade and detoxify two representative alkylphenol pollutants, 4-n-octylphenol and 2-phenylphenol, was systematically studied. Gl-LAC-4 laccase had a very strong ability to degrade high concentrations of 4-n-octylphenol, 2-phenylphenol, and alkylphenol mixtures. The degradation speed of Gl-LAC-4 toward 2-phenylphenol was very fast. Gl-LAC-4 displayed strong tolerance for a variety of metal salts and organic solvents in the degradation of alkylphenols. Gl-LAC-4 showed strong tolerance for high concentrations of various metal salts, such as MgSO4, MnSO4, Na2SO4, CuSO4, ZnSO4, CdSO4, and K2SO4, in the degradation of 4-n-octylphenol and 2-phenylphenol.In the case of the same metal cation, the inhibitory effect of the metal salt with Cl- as the anion on the degradation of 4-n-octylphenol and 2-phenylphenol by laccase was stronger than that of the metal salt with SO42- as the anion. An increase in the number of chloride ions caused a greater inhibitory effect on alkylphenol degradation by laccase. Gl-LAC-4 exhibited strong tolerance for glycerol, ethylene glycol, butanediol, propylene glycol, and organic solvent mixtures in the degradation of alkylphenols. Gl-LAC-4 treatment significantly reduced or eliminated the phytotoxicity of 4-n-octylphenol and 2-phenylphenol.

An amino-functionalized magnetic core-shell structure metal-organic framework (MOF), Fe3O4-NH2@MIL-100 (Fe), has been successfully constructed by a step-by-step method. The composite microspheres exhibited excellent magnetic characteristics, large surface area, and pore size, which were employed for the Trametes versicolor laccase immobilization. The immobilized laccase exhibited high activity recovery (72.05%) and significantly improved stability. The reactive activity remained 75% of its initial activity after storage for 4 weeks. Additionally, when the ambient reached 80 °C, the good stability enabled the immobilization laccase to keep 33% residual activity even after 6 h storage. Application of the immobilized laccase for environmental pollutant alkylphenol polyethoxylate (APEO) removal was also investigated. The results showed the immobilized laccase can remove 100% octylphenol polyethoxylate (OPEO) and 98.16% nonylphenol polyethoxylate (NPEO) in 200 min, and can still achieve 63.42% and 46.17% removal efficiency for OPEO and NPEO after reusing four cycles, respectively. The novel MOF based core-shell magnetic composite microspheres introduced by this study showed promising applications as laccase immobilization support, and both the immobilized laccase and its support had great potential in wastewater treatment.

Endocrine disrupting compounds (EDCs) have been widely reported as potential carcinogenic threats to the human population. The release of EDCs to environmental compartments, such as water, sediment, and biota, has been monitored extensively. Considering the typically low levels of EDC concentrations found in environmental samples and the complexity of biota matrices, the main challenge is with the extraction and cleanup of samples, as well as with finding a sensitive enough instrumentation system for analyte detection. This paper presents a review of recent trends in the analysis of EDCs in environmental matrices. The focus of this review is three classes of environmentally important EDCs; namely, pharmaceuticals, estrogenic hormones, and alkylphenol compounds. Discussions about state-of-the-art instrumentation and sample preparation techniques, as well as a review of sample storage and preservation, are highlighted. Overall, the use of LC-MS-MS as an instrumentation technique has increased over the past 15 years.

Made available in DSpace on 2018-12-11T17:07:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-11-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Universidad de Costa Rica Previous studies using in vivo bioassay guided fractionation indicated that the herbicide diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) and alkylphenol (AP)-containing surfactants were detected in fractions of extracts that induced the estrogenic biomarker, vitellogenin in fish exposed to surface water extracts from the United States. However, when the compounds were evaluated individually using in vivo estrogenic assays or in vitro estrogen receptor assays, estrogenic activity was not observed. Since APs have been shown to alter activity and content of cytochrome P450s (CYP) which convert diuron to potential estrogenic metabolites, the hepatic biotransformation of diuron was measured with and without a 7 day pretreatment of p-Octylphenol (OP) and p-Nonylphenol (NP) at low (OP 13 ng/L + NP 91 ng/L), and high concentrations (OP 65 ng/L + NP 455 ng/L) in juvenile male Nile tilapia (Oreochromus niloticus). Pre-treatment with the OP/NP (AP) mixture caused elevated levels of NADPH-catalyzed formation of 3,4-dichlorophenyl-N-methylurea (DCPMU) but not 3,4-dichlorophenylurea (DCPU). Fish were also treated with nominal concentrations of low (40 ng/L) and high (200 ng/L) diuron and each of its three degradates/metabolites: DCPMU, DCPU and 3,4-dichloroaniline (DCA). Additional treatments were conducted with APs and Diuron as a mixture at the low concentrations which mimicked concentrations observed in surface waters. Hepatic vitellogenin (Vtg) mRNA was induced by exposure to the high concentrations of Diuron, as well as DCPMU and DCPU in both concentrations. Brain cytochrome P450 aromatase activity was generally diminished by diuron, its metabolites, and the AP/diuron mixtures. 17β-Hydroxysteroid dehydrogenase (17βHSD) levels were also reduced by DCPMU and DCA in the lower concentrations, but not by higher concentrations. While the AP mixture reduced 17βHSD, the AP/diuron mixture induced testosterone (T) biosynthesis at the single concentration tested. Although CYP3A expression was induced by all diuron metabolites, it was unchanged by the AP mixture. These data indicate that mixtures of AP and diuron enhanced the formation of the metabolite (DCPMU) which induced vitellogenin, and reduced T biosynthetic enzymes (17βHSD inhibition). Overall, these data showed that APs may have induced the biotransformation of diuron to at least one metabolite, that may disrupt androgen biosynthesis and potentially alter steroid feedback pathways in the central nervous system. Department of Chemistry and Environmental Sciences Universidade Estadual Paulista (IBILCE/UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto Department of Natural Sciences Fundação Universidade Regional de Blumenau, Av. Antonio da Veiga 140, Itoupava Seca Department of Environmental Sciences University of California Riverside Department of Chemistry and Environmental Sciences Universidade Estadual Paulista (IBILCE/UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto FAPESP: 2011/52061-8 FAPESP: 2014/18825-9 CAPES: 3000-13-3 CNPq: 307603/2014-8 CNPq: 401884/2012-0

In recent years, there is a growing concern among the scientific community about the presence of the so-called emergent pollutants in waters of different countries, especially endocrine-disrupting compounds (EDCs) that have the ability to alter the hormonal system. One of the substances found almost ubiquitously and in higher concentrations is the alkylphenol nonylphenol. Albeit this compound is included in priority lists as a probable risk for human health and the environment, little is known about its effects on developing plants. The aim of this work is to assess the acute and sub-chronic toxicity of environmental concentrations of nonylphenol in riparian vascular plant development using spores of the fern Polystichum setiferum and a biomarker-based approach: mitochondrial activity (cell viability), chlorophyll (plant physiology) and DNA content (growth). Mitochondrial activity and DNA content show that nonylphenol induces acute and sub-chronic toxicity at 48 h and after 1 week, respectively. Significant effects are observed in both parameters in fern spores at ng L−1 but chlorophyll autofluorescence shows little changes. The inhibition of germination by natural allelochemicals has been reported to be related with the active hydroxyl group of phenolic compounds and largely independent of the structural nucleus to which it is attached. Results presented in this study suggest that environmental concentrations of nonylphenol could interfere with higher plant germination development by mimicking natural allelochemicals and/or phytohormones acting as a “phytoendocrine disruptor” likely posing ecophysiological risks.