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Nano-/microplastics (NMPs, particle diameter5 mm) are widespread emerging pollutants causing diverse impacts on organisms due to their sizes, shapes, and chemical properties. Despite the fast increase in NMP research, an effective method to separate and identify NMP types from environmental samples is still lacking. Here, we developed a simple and effective approach for the non-destructive extraction and separation of various types of NMPs from environmental samples by density gradient ultracentrifugation (DGU). For the first time, DGU was capable to separate various NMPs from the complex matrix with high selectivity (100%), purity (93%), and applicability. Through a gradually changing density of the density gradient medium by changing the concentrations or volumes of CsCl/water solution (from 0.00065 to 0.01989 g cm

Effective detection methods are of critical importance to food surveillance for preservatives in commercial food and beverages, aiding to avoid excessive intake by consumers. In this study, E-nose technology was combined with ANN modelling for qualitative and quantitative analysis of benzoic acid in cola-type carbonated beverages. The qualitative model generated accuracy rates of 90.0 and 92.0% in category identification for test samples with High, Medium or Low levels of benzoic acid, when performed on the testing and validating data subsets, respectively. For quantitative analysis, the predicted values of benzoic acid exhibited strong linear correlation with reference values determined with HPLC, with R2 between predicted and reference values being 0.99, for both the testing and validating data subsets; mean relative differences of predicted values compared with reference values were 4.47 ± 3.66 and 1.93 ± 3.01% for the testing and validating data subsets, respectively. Paired t-test indicated that the differences between predicted and reference values were statistically insignificant (P > 0.05). Results of this study implied that E-nose combined with ANN modelling was reliable to determine benzoic acid in carbonated beverages, and could be utilized as a useful tool for effective surveillance of benzoic acid in commercial beverages in market.

Nitrogen-containing organic pollutants (quinoline, pyridine and indole) are widely distributed in coking wastewater, and bioaugmentation with specific microorganisms may enhance the removal of these recalcitrant pollutants. The bioaugmented system (group B) was constructed through inoculation of two aromatics-degrading bacteria, Comamonas sp. Z1 (quinoline degrader) and Acinetobacter sp. JW (indole degrader), into the activated sludge for treatment of quinoline, indole and pyridine, and the non-bioaugmented activated sludge was used as the control (group C). Both groups maintained high efficiencies (> 94%) for removal of nitrogen-containing organic pollutants and chemical oxygen demand (COD) during the long-term operation, and group B was highly effective at the starting period and the operation stage fed with raw wastewater. High-throughput sequencing analysis indicated that nitrogen-containing organic pollutants could shape the microbial community structure, and communities of bioaugmented group B were clearly separated from those of non-bioaugmented group C as observed in non-metric multidimensional scaling (NMDS) plot. Although the inoculants did not remain their dominance in group B, bioaugmentation could induce the formation of effective microbial community, and the indigenous microbes might play the key role in removal of nitrogen-containing organic pollutants, including Dokdonella, Comamonas and Pseudoxanthomonas. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) analysis suggested that bioaugmentation could facilitate the enrichment of functional genes related to xenobiotics biodegradation and metabolism, probably leading to the improved performance in group B. This study indicated that bioaugmentation could promote the removal of nitrogen-containing organic pollutants, which should be an effective strategy for wastewater treatment.

A method consisting of solid-phase isotope dansylation (derivatization with dansyl chloride) and liquid chromatography-high resolution mass spectrometry (LC-HRMS) was developed for the quantitative analysis of phenolic compounds (phenols) in environmental samples. A magnetic-HLB (hydrophilic lipophilic balanced) material was synthesized and applied as an adsorbent in magnetic solid-phase extraction (MSPE) for the enrichment of the analytical targets. Furthermore, with the solid-phase isotope labeling, the desalting and removal of labeling residuals could be simplified over conventional in-solution labeling. In addition to overcoming the matrix effect by isotope dansylation, the sensitivity for the analysis of phenols by LC-HRMS was remarkably improved by over 100-fold. The method was systematically verified, and good accuracy (86.5–104.9%) and precision (

BACKGROUND: Quinoline is an ubiquitous pollutant widely spread in the environment, which can be eliminated efficiently by microbial degradation In this study, two quinoline-degrading Comamonas sp strains Z1 and Z3 were isolated from activated sludge, and the degradation characteristics and genome annotation were investigated in detail RESULTS: Strain Z1 exhibited a superior capacity for quinoline degradation, which could completely degrade 50–300 mg L−1 quinoline within 8–24 h, whereas strain Z3 required 14–36 h to remove 50–200 mg L−1 quinoline The suitable pHs for strains Z1 and Z3 were 8 0 and 7 0, respectively, and metal ions such as Mn2+, Ni2+, Cu2+, Co2+ and Hg2+ could greatly inhibit bacterial growth and quinoline degradation Intermediates of 2-hydroxyquinoline, 2,8-dihydroxyquinoline, 8-hydroxycoumarin, 2,3-dihydroxyphenylpropionic acids and 2-hydroxy-6-oxonona-2,4-diene-1,9-dioate were detected by liquid chromatography coupled to Q-Exactive high-resolution mass spectrometry Thus, the biodegradation of quinoline by Comamonas sp strains possibly proceeded via the 8-hydroxycoumarin pathway Genomic sequencing of strains Z1 and Z3 revealed a similar pattern, and a large number of functional genes were predicted to participate in degradation of aromatics The key genes responsible for quinoline degradation also were identified, such as qor, mhp and bph Furthermore, quinoline 2-oxidoreductase (Qor) from strains Z1 and Z3 displayed 47 74%–61 17% similarities with previously reported Qor, which catalyzed the first step of quinoline degradation, and the maximal specific activity in cell-free extracts of strains Z1 and Z3 was 0 264 and 0 062 U mg protein−1, respectively CONCLUSION: This study should provide efficient microbial resources and useful genomic information for quinoline bioremediation © 2020 Society of Chemical Industry

Chromium (VI) [Cr(VI)] is considered to be a serious environmental pollutant because of its highly carcinogenic and mutagenic properties. In this study, we fabricated fluorescent probes for Cr(VI) ...

Multiple enzyme-like activities of manganese oxides (MnO2) have been reported and applied in catalysis, biosensors, and cancer therapy. Here, we report that catechol can be determined colorimetrically based on the 3,3′,5,5′-tetramethylbenzidine (TMB) oxidase-like activity of δ-MnO2. The detection was based on pre-incubation of catechol containing water samples with δ-MnO2, and then the residual TMB oxidase-like activity of reacted δ-MnO2 was linearly dependent on the catechol concentration in the range of 0.5 to 10 μM. This determination method was stable at pH 3.73–6.00 and was not affected by ion strength up to 200 μM. Common co-solutes in water bodies (50 μM) have negligible effects and excellent selectivity of catechol among various phenolic compounds (15 μM) was facilitated. Both reduction and aggregation of δ-MnO2 were observed during the incubation process with catechol, and aggregation-induced TMB oxidase–mimic activity decrease was the main factor for this colorimetric determination.

Sulfonamides (SAs) are one of the most widely used antibiotics and their residuals in the environment could cause some negative environmental issues. Advanced oxidation such as Fenton-like reaction has been widely applied in the treatment of SAs polluted water. Degradation rates of 95%-99.7% were achieved in this work for the tested 8 SAs, including sulfisomidine, sulfameter (SME), phthalylsulfathiazole, sulfamethoxypyridazine, sulfamonomethoxine, sulfisoxazole, sulfachloropyridazine, and sulfadimethoxine, in the Fe

Periodate (PI)-based advanced oxidation processes are a newly discovered approach for effective pollutant elimination. In this study, we demonstrated that biochar obtained from pyrolysis of anaerobic sewage sludge without any pretreatment can be used for PI activation. The biochar obtained at 800 °C (SBC-800) exhibited the best PI activation capacity using acid organic II (AO7) as substrate. The PI activation was strongly dependent on pH and exhibited the highest AO7 removal rate at pH 3.0. Meanwhile, the anti-interference capacity with common wastewater components and reusability of the SBC-800/PI system were confirmed. Combined with the results of chemical quenching, reactive oxygen species (ROS) trapping, X-ray photoelectric spectroscopy (XPS), electrochemical and density function theory (DFT)-based calculations, singlet oxygen production and electron transfer mediated by the SBC-800-PI complex were the dominant AO7 oxidation mechanisms. This study provides easily prepared catalysts for PI activation and paves the way for solid waste recycling and reuse.

The combined effect of polystyrene (PS) particles and triphenyltin chloride (TPTCl) to the green algae Chlorella pyrenoidosa was studied. The 96 h IC50 of TPTCl to the green algae C. pyrenoidosa was 30.64 μg/L. The toxicity of PS particles to C. pyrenoidosa was size-dependent, with the 96 h IC50 at 9.10 mg/L for 0.55 μm PS but no toxicity observed for 5.0 μm PS. The exposure to 0.55 μm PS led to damage on structure of algal cells, which could in turn cause inhibition on photosynthesis and population growth of the green algae. TPTCl concentrations in test medium were lowered by 15–19% at presence of 0.55 μm PS particles, indicating a reduced bioavailability of TPTCl. In spite of this reduced bioavailability, the presence of PS increased the toxicity of TPTCl, which might be attributed to facilitated uptake of TPTCl by the green algae after the damage of cell structure. The overall results of the present study provided important information on the effect of PS on the bioavailability and toxicity of TPTCl to phytoplankton species.

In this study, an aerosol-assisted Fe

Biowaste treatment by black soldier fly larvae (BSFL, Hermetia illucens) has received global research interest and growing industrial application. Larvae farming conditions, such as temperature, pH, and moisture, have been critically examined. However, the substrate carbon to nitrogen ratio (C/N), one of the key parameters that may affect larval survival and bioconversion efficiency, is significantly less studied. The current study aimed to compare the nitrogen supplying effects of 9 nitrogen species (i.e., NH4Cl, NaNO3, urea, uric acid, Gly, L-Glu, L-Glu:L-Asp (1:1, w/w), soybean flour, and fish meal) during food waste larval treatment, and further examine the C/N effects on the larval development and bioconversion process, using the C/N adjustment with urea from the initial 21:1 to 18:1, 16:1, 14:1, 12:1, and 10:1, respectively. The food wastes were supplied with the same amount of nitrogen element (1 g N/100 g dry wt) in the nitrogen source trial and different amount of urea in the C/N adjustment trial following larvae treatment. The results showed that NH4Cl and NaNO3 caused significant harmful impacts on the larval survival and bioconversion process, while the 7 organic nitrogen species resulted in no significant negative effect. Further adjustment of C/N with urea showed that the C/N range between 18:1 and 14:1 was optimal for a high waste reduction performance (73.5–84.8%, p &lt, 0.001) and a high larvae yield (25.3–26.6%, p = 0.015), while the C/N range of 18:1 to 16:1 was further optimal for an efficient larval protein yield (10.1–11.1%, p = 0.003) and lipid yield (7.6–8.1%, p = 0.002). The adjustment of C/N influenced the activity of antioxidant enzymes, such as superoxide dismutase (SOD, p = 0.015), whereas exerted no obvious impact on the larval amino acid composition. Altogether, organic nitrogen is more suitable than NH4Cl and NaNO3 as the nitrogen amendment during larval food waste treatment, addition of small amounts of urea, targeting C/N of 18:1–14:1, would improve the waste reduction performance, and application of C/N at 18:1–16:1 would facilitate the larval protein and lipid bioconversion process.

The toxicity of polystyrene (PS) particles of different sizes was investigated using Gram-negative Escherichia coli and Gram-positive Bacillus cereus. PS particles could inhibit the cell growth of E. coli but promote the cell growth of B. cereus, and this difference might be attributed to different composition in their cell walls and the different interactions between the two bacteria and PS particles. Direct adhesion of E. coli cells on the surface of 5 μm PS microbeads by flagella was observed, indicating the putative role of E. coli on biofilm formation of plastisphere. The regulations of malondialdehyde, lactate dehydrogenase and glutathione were similar between the two bacteria, so the difference in the toxicity effect of PS between the two bacteria was not caused by the antioxidant activity. The overall results of the present study could help to understand the responses of different bacteria to microplastic exposure.

The black soldier fly (BSF), Hermetia illucens, has emerged as a promising species for waste bioconversion and source of antimicrobial proteins (AMPs). However, there is a scarcity of research on the element transformation efficiency and molecular characterization of AMPs derived from waste management. Here, food waste treatment was performed using BSF larvae (BSFL) in a C/N ratio of 21:1–10:1, with a focus on the C/N-dependent element bioconversion, AMP antimicrobial activity, and transcriptome profiling. The C-larvae transformation rates were found to be similar among C/Ns (27.0–35.5%, p = 0.109), while the N-larvae rates were different (p = 0.001), with C/N 21:1–16:1 (63.5–75.0%) being higher than C/N 14:1–10:1 (35.0–45.7%). The C/N ratio did not alter the antimicrobial spectrum of AMPs, but did affect the activities, with C/N 21:1 being significantly lower than C/N 18:1–10:1. The lysozyme genes were found to be significantly more highly expressed than the cecropin, defensin, and attacin genes in the AMP gene family. Out of 51 lysozyme genes, C/N 18:1 and C/N 16:1 up-regulated (p < 0.05) 14 and 12 genes compared with C/N 21:1, respectively, corresponding to the higher activity of AMPs. Overall, the element bioconversion efficiency and AMP expression can be enhanced through C/N ratio manipulation, and the C/N-dependent transcriptome regulation is the driving force of the AMP difference.

Polycyclic aromatic hydrocarbons (PAHs) have been known for decades to threaten human health. Various physical, chemical and biological methods have been developed to remove PAHs from different matrices. Microbial biodegradation processes are thought to be effective and environmentally friendly, but the low bioavailability of PAHs and their slow removal rate often limit the application of biodegradation. In this study, novel self-assembled PAH-degrading fungal mycelium (Penicillium oxalicum SYJ-1)-carbon nanotube (CNT) composites were applied for pyrene removal. The addition of CNTs did not affect the growth of strain SYJ-1 and promoted the total PAH removal efficiency. The composite could completely remove pyrene at 20 mg L−1 within 48 h, while the sole fungus and CNTs alone could only remove 72% and 80% of pyrene at 72 h, respectively. A cytochrome P450 inhibition experiment, together with degradation product identification and transcriptomic analysis, suggested that an intracellular PAH transformation pathway was employed by strain SYJ-1. The versatility of this assembly approach was also confirmed by adding different nanomaterials and using them to remove different pollutants. This study provides a strategy of coupling the chemical adsorption and biodegradation capacity of inorganic nanomaterials and microorganisms as composites to treat hydrophobic substrates in restricted bioreactor.

Phenylalanine (Phe) is widely present in natural water and serves as a precursor of disinfection by-products (DBPs). We reported the identification of chloramination DBPs from Phe in drinking water using ultra-high performance liquid chromatography (UHPLC) coupled with complementary high-resolution quadrupole time-of-flight (QTOF) and triple quadrupole (tQ) tandem mass spectrometry (MS/MS). In the chloraminated Phe water solution, sixteen new DBPs in a total of seventeen were identified based on their accurate mass, MS/MS spectra and 35Cl/37Cl isotopic patterns. Three of these DBPs were verified as benzamide, phenylacetamide, and p-hydroxyphenylacetamide with their standards, while the others were chlorinated derivatives of Phe, hydrazone, amidine, amide and peroxide, in which the unique structures of these DBPs were rarely reported. Their stability and formation process were investigated as well. Furthermore, a method consisting of solid phase extraction (SPE) and UHPLC-MS/MS using dynamic multiple reaction monitoring (dMRM) was developed to investigate these DBPs in authentic waters. Phe, benzamide, phenylacetamide, and N-Cl-2-phenylacetimidamide were detected in chlorinated tap water. Compared with the other identified DBPs, these three DBPs were exceptionally stable and could be formed in wide formation conditions. Our work not only provided ideas for the identification of new chloramination DBPs, but also demonstrated that some DBPs usually generated in the chloramination disinfection process could also be found in the chlorinated drinking water.

Endocrine-disrupting chemicals (EDCs) cause serious threats to human health. Five types of MnO

Estrogens distribute widely in the environment as endocrine-disrupting chemicals (EDCs), which have to be monitored to evaluate their environmental impact. Aim to improve the analytical throughput of liquid chromatography-high resolution mass spectrometry (LC-HRMS), a quadruplex stable isotope dansylation method was developed, with which three real samples could be quantitatively analyzed in one injection. As the estrogens were at trace level in complex matrices, magnetic solid-phase extraction (MSPE) was applied to enrich these analytes and remove the interfaces. By integrating MSPE and quadruplex stable isotope dansylation, a solid-phase quadruplex labeling method was developed for the LC-HRMS analysis of estrogen analogues. For the tested seven estrogens, the developed method showed low detection limits (0.1-0.5 ng/L for pond water and 0.01-0.05 μg/kg for poultry manure), good precision (RSD 5.5%) and accuracy (96.8-108.3%). The method was applied in the determination of estrogens in environmental samples, and the results revealed that all the tested estrogens were present in the estuary water (unquantifiable to 71.2 ng/L) and chicken manure (undetectable to 25.43 μg/kg).

Microplastics (MPs) are ubiquitous in wastewater treatment plants (WWTPs), but much remains to be learned about their roles in WWTPs. Herein, polyethylene terephthalate (PET) and polyethylene (PE) particles were added into sequencing batch reactors (SBRs), and the sole impacts and co-impacts of MPs with other pollutants (phenol and Cu2+) on wastewater treatment processes were evaluated. Results indicated that MPs did not significantly affect SBR performance, either alone or co-occurrence with phenol, but the co-exposure to MPs and Cu2+ severely suppressed COD removal efficiency by 37.02%-64.70%. The functional groups of activated sludge had no changes after receiving MPs, but the MPs-Cu2+ co-exposure could greatly promote the secretion of extracellular polymeric substances. Furthermore, MPs had no negative impacts on diversity, richness and structure of bacterial communities, and PET and PE showed different preferences for enrichment of bacterial populations. Moreover, the MPs-Cu2+ co-exposure obviously reduced the overall abundances of Cu-related genes in SBRs.

Marine organisms are naturally exposed to different environmental pollutants including organic pollutants and nanoparticles. The interactive effects between nanoparticles and other chemicals on aquatic organisms have raised concerns regarding the potential of nanomaterials as the vector for other chemicals. In the present study, the effect of nano zinc oxide (nZnO) on the bioavailability of triphenyltin chloride (TPTCl) was studied, and their combined acute and reproductive toxicity to the marine copepod Tigriopus japonicus were evaluated. At experimental concentration ranges of nZnO in this study, the percentage of dissolution of Zn2+ was relative stable (from 62% to 66%), and nZnO did not affect the bioavailability of TPTCl to the copepods. The acute toxicity of binary mixtures of nZnO/TPT was equivalent to that of the mixture of Zn2+/TPT. In agreement with the decrease in TPTCl's LC50 values at the presence of nZnO, their interacting effect was synergistic based on response addition response surface model, and the interacting parameter was modelled to be −1.43. In addition to acute toxicity test, reproductive toxicity tests revealed that exposure to nZnO and TPTCl didn't affect the successful mating rate and the number of nauplii in the 1st brood, but they extended the time for the eggs to hatch from 2.53 days to 3.94 and 3.64 days, respectively. The exposure to nZnO/TPTCl mixture delayed the time to hatch to 5.78 days.

Soil hydrocarbon pollution often causes the crop quality and safety issue. Therefore, a high priority is given to exploring the novel bacterial strain to sustainable green agricultural food products. Two novel crude oil-degrading bacteria were screened from the local oil-contaminated soil, which exhibited a good emulsifying capacity in their oil spreading test, showing their most clearing zone on the oil covering petri dish. Glycolipid bio-surfactant was identified by the thin-layer chromatography analysis. Gas chromatography and ultraviolet spectrophotometer (UV) methods were used to evaluate the degradation degree of alkanes and aromatic hydrocarbons in crude oil. The biodegradation ability of a single strain was inferior to mixed strains. The latter revealed that the degradation of the crude oil was 92% and 85%, respectively, when cultured at 32 °C, 150 rpm for 20 days. The hardest degraded isoprenoid alkane (pristane) could easily be degraded by these mixed strains. The effect of cadmium (Cd) on the growth of isolated strains was also studied, and the results demonstrate that crude oil-degrading bacteria isolated in the present study have shown strong endurance to Cd2+ (IC50 were 228.80 mg L−1 and 97.74 mg L−1) for Pseudomonas aeruginosa Dut-lxm0725 and Rhodococcus erythropolis Dut-lxm1018 strains, respectively. The above results suggest that present wild strains could have a good application prospect in bioremediation of crude oil-contaminated soil.

A simple analytical method combining solvent extraction and liquid chromatography-high-resolution mass spectrometry (LC-HRMS) was developed for the analysis of pesticide residues in rice bran protein powder. Owning to the high accuracy of HRMS in determination of mass to charge ratio (m/z), a suspect screen of pesticide residues was performed by LC-HRMS prior to quantification analysis. Based on the theoretical m/z, four pesticides including isoprothiolane (IPT), tebuconazole (TBZ), propiconazole (PCZ), and tricyclazole (TCZ) were detected and further verified with their reference standards. The solvent extraction conditions were optimized according to the signal intensity of extracted ion chromatogram (XIC) in LC-HRMS. After optimization, 50% acetonitrile solution was adopted, in which the targeted pesticides could be extracted effectively (recoveries/accuracy of > 85%) with the good reproducibility (relative standard deviation (RSD)

Fluorescent molecularly imprinted polymers (FMIPs) were prepared in a one-pot synthesis using Mn-doped ZnS quantum dots (QDs) as a fluorescent core, sulfapyridine (SPD) as a template, methacrylic acid as a functional monomer, and ethylene glycol dimethacrylate as a cross-linker for a free-radical polymerization process. These FMIPs could be used for sensing SPD based on fluorescence quenching. As the concentration of Mn2+ in the QDs changed, the fluorescence response of the FMIPs toward SPD also varied. The optimum concentration of Mn2+ for the preparation of Mn-doped ZnS QDs was 2.5 mmol. Under the optimum conditions, the obtained FMIPs showed good binding capacity and high selectivity, and specificity toward SPD. The fluorescence intensity of the FMIPs decreased as the concentration of SPD increased in the range of 0–80 μM, with a detection limit of 0.5 μM. The FMIPs exhibited selectivity towards SPD over its structural analogs sulfanilamide, sulfathiazole, sulfamethoxazole, sulfadiazine, sulfamerazine, sulfamethazine, and sulfacetamide. Finally, the FMIPs were successfully applied to detect SPD in tap water samples, and the average recoveries of SPD at three spiking levels ranged from 95.6% to 99.8% with relative standard deviations below 1.4%. This work provides a free-radical polymerization fabrication method for fluorescent MIP sensors, which can be used for rapid recognition and determination of sulfonamides from complex matrices.

Fluorescent magnetic molecularly imprinted polymers (FMMIPs) were prepared in a one-pot sol–gel polymerization process using Mn-doped ZnS quantum dots (QDs) as a fluorescent core, N-nitrosodiphenylamine (NDPhA) as a template, (3-aminopropyl) triethoxysilane (APTES) as a functional monomer, and tetraethylorthosilicate (TEOS) as a cross-linker. These FMMIPs could be used for sensing NDPhA based on their fluorescence quenching. The fluorescence intensity of the FMMIPs decreased as the concentration of NDPhA increased in the range of 0–120 μM, with a detection limit of 0.69 μM. The FMMIPs exhibited selectivity towards NDPhA over their structural analogs N-nitrosodiethylamine and sulfanilamide. Finally, the FMMIPs were successfully applied to detect NDPhA in tap water and seawater samples, and the average recoveries of NDPhA at different spiking levels ranged from 93.1% to 105.2% with relative standard deviations below 8.4%. This work provides a simple fabrication method for fluorescent magnetic MIP sensors, which can be used for the rapid determination and separation of nitrosamines from complex matrices.

An organic-silica hybrid monolithic capillary column was fabricated by crosslinking (3-aminopropyl)trimethoxysilane (APTMS) modified mesoporous carbon nanoparticles (AP-MCNs) with tetramethoxysilane (TMOS) and n-butyltrimethoxysilane (C4-TriMOS). Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy, mercury intrusion porosimetry and inverse size-exclusion chromatography characterization proved the successful immobilization of mesoporous carbon nanoparticles (MCNs). The crosslinking of AP-MCNs into the hybrid monolithic matrix has significantly increased the reversed-phase retention of alkylbenzenes and chromatographic performance for small molecules separations in comparison with the neat one without MCNs. The resulting column efficiency of the mesoporous carbon nanoparticle-based butyl-silica hybrid monolithic column (MCN-C4-monolith) was up to ca. 116,600 N/m for the capillary liquid chromatography (cLC) separation of butylbenzene. Enhanced performance of proteins separation was achieved on the MCN-C4-monolith in comparison with the butyl-silica hybrid monolithic column without MCN (C4-monolith). The separation of peptides from bovine serum albumin (BSA) digest was carried out on the MCN-C4-monolith by capillary liquid chromatography–tandem mass spectrometry (cLC–MS/MS) with protein sequence coverage of 81.9%, suggesting its potential application in proteomics.

This study comprehensively investigated the feasibility of biogenic selenium nanomaterials (Se NMs) as a photocatalyst in dye degradation. The marine selenite-reducing bacterium Lysinibacillus sp. ZYM-1 was isolated. This strain can reduce selenite to Se NMs over a wide range of pH (5–9), selenite concentration (1–25 mM), and temperature (20–50 °C) within 48 h. Draft genome data suggested that sulfite reductase may be responsible for selenite reduction. Biogenic Se NMs generated under different conditions were subsequently characterized. The morphology and size of Se NMs were dependent on medium composition, pH, incubation time, selenite concentration, and temperature. Se nanospheres (Se NSs) exhibited significant visible light-driven photocatalytic activity on Rhodamine B (RhB) with H2O2. Three N-deethylation intermediates and phthalic acid were identified as degradation products of RhB by using liquid chromatography-high resolution mass spectrometry (LC-HRMS), indicating the coexistence of chromophore c...

Boosting the low catalytic activity of bacteriogenic Ag/AgCl nanoparticles (NPs) by adding Co2+ in a model reaction, i.e. p-nitrophenol (PNP) reduction, was observed. Under optimal conditions, Co–Ag/AgCl NPs show an apparent rate constant (kapp) of 0.0837 s−1 upon PNP reduction. Considering the trace amount of Co–Ag/AgCl NPs used in catalysis (about 1.2 μg), the activity parameter κ (which is the ratio of kapp and catalyst mass) can reach more than 6.97 × 104 s−1 g−1, which is 214-fold higher than that of pristine Ag/AgCl NPs. Meanwhile, this κ value is also the highest value reported to date. In addition, the biogenic Co–Ag/AgCl NPs exhibit superior catalytic activities over other substrates, such as m-nitrophenol, o-nitrophenol, methyl orange and rhodamine B. The activity enhancement mechanism is supposed to be that Co2+ acts as a Lewis acid, and coordinates with the surface peptides to affect the electric field distribution at the Ag/AgCl NP interface.

Multiple enzyme-like activities of manganese oxides (MnO

Phenolic wastewater containing phenol and 4-chlorophenol pose a risk to the environment and to human health. Treating them using chemical-biological coupling method is challenging. In this study, manganese oxidizing bacteria (MnOB) were enriched in moving bed biofilm reactor (MBBR) using synthetic phenol wastewater (800 mg L−1) to facilitate in situ production of biogenic manganese oxides (BioMnOx) after 90 days of operation. Then, 4-chlorophenol (4-CP) was added to the MBBR to simulate mixed phenolic wastewater. Comparing the MBBR (R1) without feeding Mn(II) and the MBBR with BioMnOx (R2) production, R2 exhibited robust phenol and 4-CP removal performance. 16S rRNA gene sequencing was employed to determine the microbial community. Subsequently, a batch experiment demonstrated that partly purified BioMnOx does not exhibits a capacity for phenol removal, but can efficiently remove 4-CP. Interestingly, 5-chloro-2-hydroxymuconic semialdehyde was found in the products of 4-CP degradation, which was the unique product of 4-CP degradation by catechol 2,3-dioxygenase (C23O). In both reactors, only catechol 1,2-dioxygenase (C12O) activity from microbes can be detected, indicating that the existence of BioMnOx provide an alternative pathway in addition to microbe driven 4-CP degradation. Overall, MBBR based MnOB enrichment under high phenol concentration was achieved, and 4-CP/phenol removal can be accelerated by in situ-formed BioMnOx. Considering the C23O-like activity of BioMnOx, our results suggest a new coupling strategy that involves nanomaterials and a microbial consortium.

Marine organisms are often exposed to a mixture of various pollutants in marine environment (i.e., nanoparticles, organic pollutants). The present study investigated the potential effects of multi-walled carbon nanotubes (MWCNTs) on the toxicity of triphenyltin chloride (TPTCl). The results revealed an antagonistic interaction between MWCNTs and TPTCl on the copepod through 96 h acute exposure, which was attributed to the adsorption of TPTCl to MWCNTs and aggregation of MWCNTs in the test solutions. Results of 21 days’ chronic exposure showed that the effect concentration of MWCNTs could be 100 times lower than that of acute exposure. The exposure to binary mixture of MWCNT (1.0 mg/L) and TPTCl (0.3 µg/L) caused a reduction by 94% for the 3rd time spawning and 83% for the total number of hatched nauplii. The ingestion and exterior attachment of MWCNTs to the copepod might be the main reasons causing the adverse effect in reproduction.

Prorocentrum lima is a dinoflagellate that forms hazardous blooms and produces okadaic acid (OA), leading to adverse environmental consequences associated with the declines of zooplankton populations. However, little is known about the toxic effects and molecular mechanisms of P. lima or OA on zooplankton. Here, their toxic effects were investigated using the brine shrimp Artemia salina. Acute exposure of A. salina to P. lima resulted in lethality at concentrations 100-fold lower than densities observed during blooms. The first comprehensive results from global transcriptomic and metabolomic analyses in A. salina showed up-regulated mRNA expression of antioxidant enzymes and reduced non-enzyme antioxidants, indicating general detoxification responses to oxidative stress after exposure to P. lima. The significantly up-regulated mRNA expression of proteasome, spliceosome, and ribosome, as well as the increased fatty acid oxidation and oxidative phosphorylation suggested the proteolysis of damaged proteins and induction of energy expenditure. Exposure to OA increased catabolism of chitin, which may further disrupt the molting and reproduction activities of A. salina. Our data shed new insights on the molecular responses and toxicity mechanisms of A. salina to P. lima or OA. The simple zooplankton model integrated with omic methods provides a sensitive assessment approach for studying hazardous algae.

Quantification of organic pollutants in flowback and produced water is essential to design appropriate treatment strategy and predict the potential environmental toxicity associated with unconventional energy production. Herein, we firstly characterized the important range chemicals of produced water (PW) collected from Weiyuan shale gas play, China. Ultra-high resolution (>10 M) electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry was used to gain insights into molecular compositions of mass range 170–1,000 Da. Oxygen-containing organic compounds (CHO) was the dominant type of compounds in the PW, and classes of O8 and O9 had the highest relative abundance. Highly unsaturated phenolic and aliphatic compounds were identified as the main compounds. Three low molecular weight (LMW

Endocrine-disrupting chemicals (EDCs) cause serious threats to human health. Five types of MnO2 were synthesized and characterized. They exhibited different removal performances for three EDCs, i.e., estrone (E1), ethynylestradiol (EE2) and bisphenol A (BPA). Only δ-MnO2 can completely remove E1 within 120 min at pH 3.0. Free Mn (III) was determined at the beginning of the reaction and participated in the EDCs removal process. Electron spin resonance (ESR) indicated that δ-MnO2 could produce superoxide anions (·O2−) and singlet oxygen (1O2) in the existence of methanol. The reactive oxygen species (ROS) quenching experiments showed 1O2 have certain contribution to the E1 removal by δ-MnO2. The source of ROS is mainly the lattice oxygen from δ-MnO2, and can be replenished through the layer structure destruction caused by the reaction between Mn(III) and E1. The ROS dependent EDCs removal by δ-MnO2 leads to a deep understanding on this well-known oxidant.

Polyethylenimine (PEI) and 2,4,6,8-tetramethyl-2,4,6,8-tetrakis(propyl glycidyl ether)cyclotetrasiloxane (POSS–epoxy) were used as precursors for the preparation of organic-silica hybrid monolithic columns (PEI–POSS monolith) via epoxy–amine ring-opening polymerization (ROP). The high density of amine groups in PEI provides rich chromatographic interaction sites for the polar or acidic analytes in hydrophilic interaction (HILIC) and weak anion exchange (WAX) mechanisms. The column preparation conditions, such as the porogens, solvent and reaction temperature, were systematically investigated according to the morphology, permeability and column efficiency. The separation mechanisms of HILIC and WAX were evaluated with neutral polar compounds and halogen benzoic acids. Owing to the existence of reactive amine groups on the matrix surface, the PEI–POSS monolith is also an ideal starting material for the preparation of HILIC or strong anionic exchange (SAX) stationary phases by modification. The modification of PEI–POSS monoliths with iodomethane or bromoacetic acid via the nucleophilic substitution reaction could achieve the retention mechanisms of SAX or zwitterionic HILIC, respectively.

Tiny changes in the mass of the sensor in a quartz crystal microbalance with dissipation monitoring (QCM-D) can be observed. However, the lack of specificity for target species has hindered the use of QCM-D. Here, molecularly imprinted polymers (MIPs) were used to modify a QCM-D sensor to provide specificity. The MIPs were formed in the presence of sodium dodecyl benzene sulfonate. Imprinted layers on Fe3O4 nanoparticles were formed using pyrrole as the functional monomer and cross-linker and methylene blue (MB) as a template. The MIPs produced were then attached to the surface of a QCM-D sensor. The MIPs-coated QCM-D sensor could recognize MB and gave a linear response in the concentration range 25 to 1.5 &times, 102 &micro, g/L and a detection limit of 1.4 &micro, g/L. The QCM-D sensor was selective for MB over structural analogs. The MIPs-coated QCM-D sensor was successfully used to detect MB in river water and seawater samples, and the recoveries were good. This is the first time MB has been detected using a QCM-D sensor. Mass is an intrinsic property of matter, so this method could easily be extended to other target species by using different MIPs.

Paralytic shellfish toxins (PSTs) cause risks to human health through food chains. Understanding the change of PSTs in seawater is critical for predicting the safety of seafood. Most reported methods for the detection of PSTs in microalgae or shellfish are not applicable in seawater because of extremely low concentration and matrix interferences. High resolution mass spectrometry (HRMS), quadrupole exactive orbitrap detects molecular ions accurately, and molecularly imprinted solid-phase extraction (MISPE) is recognized effective to reduce the matrix interference. GTXs 2&3 are two of common marine toxins in PSTs. In this study, a sensitive method consisting MISPE and liquid chromatography LC-HRMS was developed for the detection of GTXs 2&3 with a limit of detection (LOD) of 47.4 ng/L in seawater. With this method, samples obtained from the estuaries of the Shuangtaizi and Daliao Rivers were analyzed, and the results indicated the concentrations were lower than LOD in the area under investigation.

Heterogeneous activation of sulfite by synthetic lithium cobalt oxide (LCO) to treat simulated dye wastewater is developed in this study using Rhodamine B (RhB) as the model pollutant. Synergistic, independent and antagonistic interactions between LCO and Na2SO3 were observed under acid (pH = 3), neutral and alkaline (pH = 10) conditions, respectively. A high mineralization rate of 84% was obtained with 200 mg of LCO and 50 mg of Na2SO3 at pH = 3 for 50 mL of 5 mg L−1 RhB substrate. Even hand-shaking with 13 mg of LCO and 3 mg of Na2SO3 for only 30 s could realize full de-colorization. Moreover, one-time dosage of 13 mg of LCO and 3 mg of Na2SO3 worked effectively in twenty consecutive batches only if Na2SO3 was periodically supplemented. The radical-trapping experiments determined the SO 3 • - radical as the dominant reactive species and oxygen vacancies were responsible for sulfite activation. In addition to RhB, the sulfite-enhanced protocol has been universally demonstrated with methyl blue and methyl orange. This paper reflects well the sustainability concept of reusing “wastes” for pollution control since LCO is a key component in the cathode material of abandoned lithium-ion batteries and sulfites are the byproducts of flue gas desulfuration.

A simple magnetization method was developed for the preparation of magnetic materials from conventional solid phase packing though coprecipitation and solvothermal approaches. And the prepared magnetic materials were used for magnetic solid phase extraction (MSPE) of biogenic amines (BAs) from beers. Furthermore, to improve the analytical throughput, a solid phase “on-situ” quadraplex isotope dimethyl labeling method was developed for the quantification of BAs by liquid chromatography-high resolution mass spectrometry (LC HRMS). Compared to conventional in-solution labeling, the “on-situ” labeling could simplify the sample preparation procedure and efficiently remove the residuals such as inorganic salts and excessive labeling reagents. The quadraplex labeling, which enabled three real samples and one internal standard sample to be analyzed simultaneously in a single LC HRMS run. For the tested 8 BAs (cadaverine, phenethylamine, spermine, spermidine, tyramine, histamine, putrescine and tryptamine), LODs of 0.02–0.05 μg/L and LOQs of 0.05–0.1 μg/L were achieved at good reproducibility (RSD of 0.5–4.6% and 2.2–7.0% for intra- and inter-day reproducibility, respectively). With this method, six beer samples were analyzed, and these 8 BAs were all detected in the range of low μg/L to 2.9 mg/L, which were lower than maximal residual level (MRL) required in the regulations of China and EU.

A simple modification method was developed for the functionalization of amino terminated carbon nanotubes (CNT-NH2) by using isocyanates as modifiers via the nucleophilic addition reaction. Two types of functionalized magnetic carbon nanotubes (MCNT) were prepared through deposition of magnetic nanoparticles on CNT-NH2 and modification with different isocyanates. p-Tolyl-functionalized MCNT (Tol-MCNT) with better adsorption performance were selected as adsorbent for magnetic solid phase extraction (MSPE), which could extract sulfonamides (SAs) from various milk samples with a enrichment factor of about 30 after optimization. By combining the MSPE with liquid chromatography–high resolution mass spectrometry (LC–HRMS), a new method was developed. Both skimmed and whole milk samples of three brands were analyzed with this method, and 4 SAs including sulfadiazine, sulfisomidine, sulfamethazine and sulfameter were detected with the concentration from unquantifiable to 72 ng/L, which were all well below the maximum residue limits in milk according to the regulations of China and EU.