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Fe0-based heterogeneous Fenton process has been increasingly developed for organic pollutants removal. However, the reaction activity of Fe0 catalyst is easily weakened due to the formation of dense oxide layer or the precipitation of iron hydroxides on the surface. Herein, the effect and mechanism of magnetic field (MF), visible light (Vis), nitrilotriacetic acid (NTA) and inorganic salt ions on the Fe dissolution and dimethyl phthalate (DMP) degradation in the Fe0/H2O2 system were investigated. The results showed that the magnetic field (100 mT), NTA and inorganic salt ions effectively enhanced the dissolution of Fe from the surface of iron filings, and visible light significantly accelerated the Fe3+/Fe2+ cycle in the aqueous phase, which promoted the decomposition of H2O2 by Fe2+ to generate •OH and further enhanced the degradation of DMP. DMP was nearly completely degraded within 60 min in the pH range of 3.0–9.0, indicating the MF/Vis/NTA/Fe0/H2O2 system effectively broadened the pH range of Fenton-like system. The iron sand column tests proved that the MF/solar/NTA/Fe0/H2O2 system was effective for the treatment of waste leachate reverse osmosis concentrate as a typical actual high-salt wastewater, in which the removal rates of chemical oxygen demand and humic acid reached 84.5 and 90.6%, and the chromaticity was almost completely removed. Generally, the activation mechanism of Fe0-based heterogeneous photo-Fenton system was set up and an effective method for organic pollutant removal and high-salt wastewater treatment was provided. [ABSTRACT FROM AUTHOR]

Aim: The present work explored the mechanism of dimethyl phthalate (DMP, the environmental contaminant) exposure in inducing cognitive impairment. Methods: Targets and regulatory networks related to DMP-brain injury-cognitive impairment were analyzed through network pharmacology. DMP exposure was carried out to simulate DMP environmental uptake, whereas Morris water maze was performed for examining cognitive impairment. Additionally, inflammatory cytokine levels within tissues were measured. hematoxylin-eosin staining(H&E) and Nissl staining was conducted to examine brain tissue injury, while Western blot was carried out for identifying protein levels. After applying.Small interfering RNA(siRNA-COX2) and celecoxib-COX2 inhibitors separately, we analyzed impacts of DMP. Besides, in vitro experiments were performed to analyze impacts of DMP on microglial activation. Results: As suggested by network pharmacology,Cyclooxygenase-2-PTGS2 (COX2) showed significant relation to DMP, and it exerted its effect via COX2. Following DMP exposure, mice experienced obvious cognitive impairment and brain damage, besides, microglial cells were activated, and inflammatory cytokines were up-regulated. Applying siRNA-COX2 and celecoxib-COX2 suppressed DMP’s impact and mitigated mouse cognitive impairment. Based on in vitro analysis, DMP led to microglial activation and neuroinflammation. Conclusion: DMP exposure causes neuroinflammation via the COX2-regulated microglial activation, thus leading to cognitive impairment. COX2 may serve as the key action target of DMP.

Phthalate esters (PAEs) raised serious concerns on their health risk due to their toxicities. However, toxicities of low‐molecular‐weight PAEs, for example, dimethyl phthalates (DMPs), remained poorly investigated. In the present study, the reproductive toxicities of dimethyl (o‐)phthalate (DMOP), dimethyl (p‐)phthalate (DMPP), and dimethyl (m‐)phthalate (DMMP) were measured on Caenorhabditis elegans with mechanical exploration. Results showed that DMPP, DMOP, and DMMP commonly inhibited the total reproduction while stimulated lifespan, showing trade‐off effects. In effects on gene expressions, DMPP, DMOP, and DMMP caused different regulations on the expressions of vab‐1, ceh‐18, and gsa‐1 which are involved in oocyte growth, ovulation, and maturation. Meanwhile, they commonly downregulated those of rme‐2 and rcy‐4 that regulate germ cells and gonads and lipid metabolism in oocytes. Moreover, the effects on biochemicals that regulate reproductive processes showed alteration between stimulation and inhibition over life stages. In addition, effects at apical, biochemical, and molecular levels clearly showed the structure influences on the toxicities. Summing up, reproductive toxicities of DMPs depended on the exposure life stages and also the chemical structures. [ABSTRACT FROM AUTHOR]

Biosorption provides the reduction of pollution effluents to environmentally satisfactory cutoff points in a financially savvy and ecologically benevolent way by using microorganisms and nanotechnology. Due to its availability and dimethyl phthalate sorption capability, Saccharomyces cerevisiae was considered for the biosorption of dimethyl phthalate in the last decade. In this study, dried S. cerevisiae with silver nanoparticle was used for dimethyl phthalate biosorption. The influence of operative conditions such as pH, temperature, initial DMP concentration, adsorbent dosage, and contact time is examined. Optimization of operational parameters shows that the optimum concentrations of YB-AgNPs for effective removal of DMP were 700 µg/mL at pH 5 after 5 min and 0.5 g at 30–50 °C for YB-AgNP biomass concentration. Using three isothermal models, the data obtained from the experiment were analyzed, and the parameters were estimated for each isothermal and related coefficient. The Langmuir isotherm model in this study suits best for the biosorption of dimethyl phthalate. To evaluate biosorption kinetics, three kinetic models were used, and it was observed that biosorption follows a second pseudo-order model of a ratio coefficient as high as R2 = 1. The analysis of thermodynamics test data revealed that the process was spontaneous and feasible. The mechanism of biosorption was defined as physisorption. Therefore, the results obtained show that inactive YB-AgNPs can be an easy and affordable alternative to costly activated carbon for the treatment of dimethyl phthalate from wastewater. [ABSTRACT FROM AUTHOR]

Homogeneous electro-Fenton technology is a promising approach for treating the increasing numbers of refractory organic pollutants in water. However, it has disadvantages, such as a narrow pH usage range and the generation of secondary pollution during the actual treatment process. In this study, waste wine lees were used as biomass carbon precursors to prepare nitrogen and oxygen co-doped biomass carbon-loaded Fe3O4 composites (Fe3O4@NOPC), thus constructing a heterogeneous electro-Fenton system to solve such problems. The results showed that the porous structure and rich surface functional groups of biomass carbon can act as carrier and accelerate the intermediate mass transfer. The degradation efficiency of dimethyl phthalate (DMP) reached 70% within 5 h by doping Fe3+/Fe2+ at the ratio of 2:1 without an additional of iron source; the conversion of Fe3+ to Fe2+ can be accelerated by an appropriate ratio. The degradation mechanism indicated that in addition to •OH radicals, a part of electro-oxidation and adsorption act together to play a degradation role. During the initial electro-Fenton reaction, the loaded Fe3O4 nanoparticles act as an iron source to reduce the production of iron-containing sludge and avoid secondary pollution. This provides a completely new idea to reduce the cost of electro-Fenton, effectively utilize waste resources, and reduce sludge production. [ABSTRACT FROM AUTHOR]

Microplastics, derived from the decomposition of plastics, can be identified in almost any type of surface water. Various pollutants, which are often toxic and hardly biodegradable, can leach from these particles. For this reason, it is important to know the possibilities of their effective removal from water. The tests carried out were aimed at determining the effectiveness of removing the tested substances from water - isophorone, dimethyl phthalate, and 4-tert-octylphenol in membrane processes using the following membranes: NF270, BX, V5, as well as adsorption on powdered activated carbon. The tests using membrane techniques consisted of passing the feed (water solution of the tested pollutants) under high pressure through the membrane, which was collected as permeate after filtration. The membrane was conditioned before testing. During the test with the use of activated carbon, its sorption properties were tested at varying doses of activated carbon in the samples (and constant concentrations of pollutants in water) and at different times of contact with pollution (at constant doses of activated carbon and constant concentration of pollutants in water). Studies using ultra- and nanofiltration membranes have shown that the type of membrane had a significant impact on the effectiveness of the pollutant removal process. The highest efficiency was obtained using a nanofiltration membrane for all tested substances. The conducted adsorption tests showed that the concentration of the tested pollutants decreases with the increase in the dose of activated carbon and the extension of the contact time of the pollutant with the sorbent. Comparing the effectiveness of the processes used to remove the tested pollutants leached from microplastics, it can be concluded that greater efficiency was obtained in the adsorption process on activated carbon. [ABSTRACT FROM AUTHOR]

Total or partial replacement of styrene with low volatilities diluents can be considered the most effective way to reduce the environmental risks and destructive effects of styrene release on human health. In this respect, phthalic acid-derived diluents are ideal candidates to replace styrene because of their easy availability, low volatility, and inexpensive. In the present study, a reactive diluent (D1) was synthesized from dimethyl phthalate (Dp) and hydroxyl ethyl methacrylate (HEMA) to produce a copolymer with epoxy acrylate (EA) resin. Nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) confirmed the chemical structure of synthesized diluents and EA resins. Also, the viscosity, thermal stability, and mechanical properties of EA resin samples were investigated using the rheology test, thermogravimetric analysis, tensile test, and flexural test. The results showed that diluent D1 (active diluent) is more effective than Dp (deactivated diluent) and styrene, especially in reducing the viscosity of EA resins. Overall, the great effect of diluent D1 in improving the rheological properties (before curing) and the thermal stability and mechanical properties (after curing) of EA resins make this diluent a suitable alternative to styrene in the production of commercial EA resins. [ABSTRACT FROM AUTHOR]

Among the bismuth oxyhalides, bismuth oxide has the shortest band gap and high absorption power in the visible light region. Dimethyl phthalate (DMP) has been identified as endocrine-disrupting plasticizer and emerging pollutant, which was selected as the target pollutant to evaluate the efficacy of the studied catalytic process. In this work, Bi7O9I3/chitosan and BiOI/chitosan were efficaciously synthesized by the hydrothermal process method. Characterizing prepared photocatalysts was done by employing transmission electron microscopy, X-ray diffraction, scanning electron microscopy energy-dispersive spectroscopy, and diffuse reflectance spectroscopy. For this study, the test design was performed using the Box–Behnken Design (BBD) method in which the variables of pH, Bi7O9I3/chitosan dose, and dimethyl phthalate concentration were examined for the catalytic removal of dimethyl phthalate in the presence of visible light. Our detected results disclosed that the order of efficiency in DMP removal was as follows: Bi7O9I3/chitosan > BiOI/chitosan > Bi7O9I3 > BiOI. Also, the maximum pseudo-first-order kinetic coefficient for Bi7O9I3/chitosan was 0.021 (min)−1. When the synthesized catalysts were exposed to visible light irradiation, the predominant active species were O2− and h+ for degradation of DMP. The study on the reuse of Bi7O9I3/chitosan showed that this catalyst could be reused 5 times without significant reduction in efficiency, which indicates the cost-effectiveness and environmental friendliness of using this catalyst. [ABSTRACT FROM AUTHOR]

Dimethyl phthalate is low molecular weight phthalate used on a wide scale within industry for manufacture of plastics, solvents, adhesives, lubricants, coatings and due to its poor biodegradability is not removed by classic wastewater treatment processes. It was proved that it affects the endocrine system, presenting carcinogenic, teratogenic and mutagenic effects on upon living organisms. Therefore, there is a need for more advanced treatment methods such as advanced oxidation processes for dimethyl phthalate removal from aqueous systems. A hybrid process consisting from photo catalysis and membrane based processes was investigated and the optimum parameters for dimethyl phthalate removal were established. In respect to photocatalytic process the influence of photo catalyst dose, pH, irradiation time were studied and process kinetics were set up using a synthetic dimethyl phthalate solution. In order to recover and reuse the photocatalyst a membrane process was used and optimum working pressure was determined. In the case of real wastewater matrix the addition of hydrogen peroxide was needed, in the photocatalytic stage, in order to improve process efficiency. Four treatment cycles, using real wastewater spiked with dimethyl phthalate, were performed with the reuse of photo catalyst proving that the use of photocatalytic membrane reactor with suspended photo catalyst represents a promising method for phthalates removal from aqueous systems.

This study is the first to explore the possibility of utilizing CuCr LDH decorated on reduced graphene oxide (rGO) and graphene oxide (GO) as sonophotocatalysts for the degradation of dimethyl phthalate (DMP). CuCr LDH and its nanocomposites were successfully fabricated and characterized. Scanning electron microscopy (SEM) along with high-resolution transmission electron microscope (HRTEM) both evidenced the formation of randomly oriented nanosheet structures of CuCr LDH coupled with thin and folded sheets of GO and rGO. The impact of diverse processes on the degradation efficiency of DMP in the presence of the so-prepared catalysts was compared. Benefiting from the low bandgap and high specific surface area, the as-obtained CuCr LDH/rGO represented outstanding catalytic activity (100 %) toward 15 mg L−1 of DMP within 30 min when subjected to light and ultrasonic irradiations simultaneously. Radical quenching experiments and visual spectrophotometry using an O-phenylenediamine revealed the crucial role of hydroxyl radicals compared to holes and superoxide radicals. Overall, outcomes disclosed that CuCr LDH/rGO is a stable and proper sonophotocatalyst for environmental remediation.

Introduction: Dimethyl phthalate (DMP) which has been widely detected in water is neurotoxic to humans and should be effectively eliminated. Persulfate-based advanced oxidation processes are considered to be reliable methods aiming at emerging contaminants degradation, while an efficient catalyst is urgently needed for the activation of the reaction. As a typical 2D material, 1T-MoS2 is expected to be applied to the activation of persulfate owing to its abundant active sites and excellent electrical conductivity. In practical applications, 1T-MoS2 has the phenomenon of reunion which affects the exposure of its catalytic sites.Methods: Therefore, in this study, we used waste cow manure as a raw material to prepare biochar and achieved high exposure of 1T-MoS2 activation sites by loading 1T-MoS2 onto the surface of cow manure biochar through hydrothermal synthesis. The prepared composite catalytic material CMB@1T-MoS2 was used to activate PMS for the degradation of DMP.Results: It was found that CMB@1T-MoS2 has better effect than CMB or 1T-MoS2 alone for the degradation of DMP, reaching 77.65% at pH = 3. Under alkaline conditions, the degradation rate of DMP was reduced due to the inhibition of the catalytic process. Among the different coexisting anions, HCO-3 interfered and inhibited the degradation process the most, leading to the lowest degradation rate of DMP with 42.45%.Discussion: The quenching experiments and EPR analysis showed that SO-4• and •OH were the main ROS in the CMB@1T-MoS2/PMS process. This study promotes the resourceful use of cow manure and is expected to provide a novel persulfate-based advanced oxidation process catalyzed by CMB@1T-MoS2 for the elimination of DMP in an aqueous environment.

Dimethyl phthalate (DMP) is one of the most widely used plasticizers, and it is easily released into the environment, posing a threat to microbes. In this study, the impact of DMP on the uptake and metabolism of sugars in E. coli K-12 was assessed using proteomics, computational simulation analysis, transcriptome analysis, and sugar utilization experiments. DMP contamination inhibited the growth of E. coli K-12 and downregulated the expression of proteins in ATP-binding cassette (ABC) transporters and the phosphotransferase (PTS) system of E. coli K-12, which are primarily involved in the transmembrane transport of sugars. DMP formed a stable complex with sugar transporters and changed the rigidity and stability of the proteins. Furthermore, DMP treatment decreased the utilization of L-arabinose, glucose, D-xylose, and maltose. Moreover, carbon metabolism and oxidative phosphorylation were also downregulated by DMP. Our study shows that DMP reduces the uptake of sugars and ATP production and subsequently inhibits the growth of E. coli K-12. [ABSTRACT FROM AUTHOR]

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Taking dimethyl phthalate (DMP) as the target pollutant, the removal effects of three commonly used advanced oxidation technologies (O3 oxidation, UV/H2O2 and Fenton Method) on DMP in water were studied. The single factor method was used to investigate the influencing factors of DMP degradation. The response surface analysis method was used to optimize the process conditions of each process, and the costs of the three methods were compared. The single factor experiment results show that for DMP with an initial concentration of 50 mg/l, the optimal conditions for O3 oxidation reaction are O3 concentration of 15mg/l and pH value of 9, UV/H2O2 reaction conditions are UV power of 300 W, H2O2 dosage of 180 mg/l and pH value of 5, and Fenton Method conditions are Fe2SO4 concentration of 60 mg/l, pH value of 3 and H2O2 dosage of 180 mg/l. The degradation rates of DMP by various processes are comprehensively compared, The degradation effects of three advanced oxidation methods on DMP were as follows: UV/H2O2> O3> Fenton, and the degradation cost from high to low was UV/H2O2>Fenton> O3. [ABSTRACT FROM AUTHOR]

The present work explored the mechanism of dimethyl phthalate (DMP, the environmental contaminant) exposure in inducing cognitive impairment. Targets and regulatory networks related to DMP-brain injury-cognitive impairment were analyzed through network pharmacology. DMP exposure was carried out to simulate DMP environmental uptake, whereas Morris water maze was performed for examining cognitive impairment. Additionally, inflammatory cytokine levels within tissues were measured. hematoxylin-eosin staining(H&E) and Nissl staining was conducted to examine brain tissue injury, while Western blot was carried out for identifying protein levels. After applying.Small interfering RNA(siRNA-COX2) and celecoxib-COX2 inhibitors separately, we analyzed impacts of DMP. Besides, in vitro experiments were performed to analyze impacts of DMP on microglial activation. As suggested by network pharmacology,Cyclooxygenase-2-PTGS2 (COX2) showed significant relation to DMP, and it exerted its effect via COX2. Following DMP exposure, mice experienced obvious cognitive impairment and brain damage, besides, microglial cells were activated, and inflammatory cytokines were up-regulated. Applying siRNA-COX2 and celecoxib-COX2 suppressed DMP's impact and mitigated mouse cognitive impairment. Based on in vitro analysis, DMP led to microglial activation and neuroinflammation. DMP exposure causes neuroinflammation via the COX2-regulated microglial activation, thus leading to cognitive impairment. COX2 may serve as the key action target of DMP. • DMP exposure can induce neuroinflammation through COX2-mediated activation of microglia. • COX2 is an important target for DMP action. • Neuroinflammation is an important mechanism of DMP toxicity, and COX2 is a major target for DMP action. [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs) are emerging hazardous and toxic chemicals that are extensively used as plasticizers or additives. Diethyl phthalate (DEP) and dimethyl phthalate (DMP), two kinds of PAEs, have been listed as the priority pollutants by many countries. PAE hydrolases are the most effective enzymes in PAE degradation, among which family IV esterases are predominate. However, only a few PAE hydrolases have been characterized, and as far as we know, no crystal structure of any PAE hydrolases of the family IV esterases is available to date. HylD1 is a PAE hydrolase of the family IV esterases, which can degrade DMP and DEP. Here, the recombinant HylD1 was characterized. HylD1 maintained a dimer in solution, and functioned under a relatively wide pH range. The crystal structures of HylD1 and its complex with monoethyl phthalate were solved. Residues involved in substrate binding were identified. The catalytic mechanism of HylD1 mediated by the catalytic triad Ser140-Asp231-His261 was further proposed. The hylD1 gene is widely distributed in different environments, suggesting its important role in PAEs degradation. This study provides a better understanding of PAEs hydrolysis, and lays out favorable bases for the rational design of highly-efficient PAEs degradation enzymes for industrial applications in future. [Display omitted] • The enzymatic properties of a PAE hydrolase HylD1 were characterized. • Structures of HylD1 belonging to the family IV esterases were solved. • The substrate binding pattern and catalytic mechanism of HylD1 were proposed. • The hylD1 gene is widely distributed in various environments. [ABSTRACT FROM AUTHOR]

In order to solve the problem of environmental health hazards caused by phthalate esters, a series of pure Bi2O2CO3 and light (La, Ce, Pr, Nd, Sm and Eu) and heavy (Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) rare earth-doped Bi2O2CO3 samples were prepared by hydrothermal method. The crystalline phase composition and physical structure of the samples calcined at 300 °C were studied, and we found that the rare earth ion doping promoted the transformation of Bi2O2CO3 to β-Bi2O3 crystalline phase, thus obtaining a mixed crystal phase photocatalyst constituted by rare earth-ion-doped Bi2O2CO3/β-Bi2O3. The Bi2O3/Bi2O2CO3 heterostructure had a lower band gap and more efficient charge transfer. The fabricated samples were applied to the photocatalytic degradation of dimethyl phthalate (DMP) under a 300 W tungsten lamp, and it was found that the rare earth ion doping enhanced the photocatalytic degradation activity of DMP, in which the heavy rare earth of Er-doped sample reached 78% degradation for DMP at 150 min of light illumination. In addition, the doping of rare earths resulted in a larger specific surface area and a stronger absorption of visible light. At the same time, the formation of Bi2O2CO3/β-Bi2O3 heterogeneous junction enhanced the separation efficiency of photogenerated electrons and holes. [ABSTRACT FROM AUTHOR]

In the current study, an integrated physiochemical method was utilized to remove tonalide (TND) and dimethyl phthalate (DMP) (as emerging contaminants, ECs), and nickel (Ni) and lead (Pb) (as heavy metals), from synthetic wastewater. In the first step of the study, pH, current (mA/cm2), and voltage (V) were set to 7.0, 30, and 9, respectively; then the removal of TND, DMP, Ni, and Pb with an electro-ozonation reactor was optimized using response surface methodology (RSM). At the optimum reaction time (58.1 min), ozone dosage (9.4 mg L−1), initial concentration of ECs (0.98 mg L−1), and initial concentration of heavy metals (28.9 mg L−1), the percentages of TND, DMP, Ni, and Pb removal were 77.0%, 84.5%, 59.2%, and 58.2%, respectively. For the electro-ozonation reactor, the ozone consumption (OC) ranged from 1.1 kg to 3.9 kg (kg O3/kg Ecs), and the specific energy consumption (SEC) was 6.95 (kWh kg−1). After treatment with the optimum electro-ozonation parameters, the synthetic wastewater was transferred to a fixed-bed column, which was filled with a new composite adsorbent (named BBCEC), as the second step of the study. BBCEC improved the efficacy of the removal of TND, DMP, Ni, and Pb to more than 92%. [ABSTRACT FROM AUTHOR]

Contamination of the environment by technogenic endocrine disrupting compounds (EDCs) becomes serious threat to public health. To effectively prevent this threat, it is necessary to improve analytical methods for EDCs to ensure mass, fast and productive monitoring. In the given work, a dual lateral flow test (LFT) is developed in the first time for simultaneous immunodetection of bisphenol A and dimethyl phthalate, priority EDCs releasing from plastic and belonging to different chemical classes. It combines integrated detection of two EDCs by one analytical system with rapidity and simplicity of LFTs allowing for off-lab testing without additional reagents and devices. Gold nanoparticles differing in shape and color (red gold nanospheres and blue gold nanoflowers) are applied as markers to simplify interpretation of the obtained results. Under the optimal conditions chosen for efficient control of the both analytes, the detection limits of bisphenol A and dimethyl phthalate are 0.67 ng/mL and 2.22 ng/mL, respectively. Time of the assay is 15 min. The proposed dual LFT has confirmed its practical applicability by analyzing natural water samples with recovery of bisphenol A and dimethyl phthalate in the ranges of 90.4-107.0% and 86.8-118.0%, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

A Gram-negative bacteria (Pseudomonas fluorescens) was exposed to dierent concentrations (0, 20, and 40 mg/L) of dimethyl phthalate (DMP) for 8 h, and then Fourier transform infrared spectroscopy (FTIR) analysis, lipopolysaccharide content detection, analysis of fatty acids, calcein release test, proteomics, non-targeted metabolomics, and enzyme activity assays were used to evaluate the toxicological eect of DMP on P. fluorescens. The results showed that DMP exposure caused an increase in the unsaturated fatty acid/saturated fatty acid (UFA/SFA) ratio and in the release of lipopolysaccharides (LPSs) from the cell outer membrane (OM) of P. fluorescens. Moreover, DMP regulated the abundances of phosphatidyl ethanolamine (PE) and phosphatidyl glycerol (PG) of P. fluorescens and induced dye leakage from an artificial membrane. Additionally, excessive reactive oxygen species (ROS), malondialdehyde (MDA), and changes in antioxidant enzymes (i.e., catalase [CAT] and superoxide dismutase [SOD]) activities, as well as the inhibition of Ca2+-Mg2+-ATPase and Na+/K+-ATPase activities in P. fluorescens, which were induced by the DMP. In summary, DMP could disrupt the lipid asymmetry of the outer membrane, increase the fluidity of the cell membrane, and destroy the integrity of the cell membrane of P. fluorescens through lipid peroxidation, oxidative stress, and ion imbalance [ABSTRACT FROM AUTHOR]

N-(Substituted phenyl)-2-(3H-thieno[2,3-d]imidazol-2-yl)benzamides were synthesized by one-pot three-component reaction of dimethyl phthalate, substituted anilines, and thiophene-2,3-diamine in a mixture of ethanol and water in the presence of H3PO4 as catalyst for 1.5–2.0 h at 70–75°C. The developed synthetic protocol is sustainable and economic and is characterized by easy workup procedure, the use of nontoxic reactants and solvents, short reaction time, and high yields. [ABSTRACT FROM AUTHOR]

The pretreatment process can be simplified by ferromagnetic nanomaterials, then Fe 3 O 4 @SiO 2 @Ag@MIPs selectively adsorbing DMP can be achieved by molecular imprinting technology, and SERS can be applied for DMP detection with high sensitivity. The DMP concentrations were linearly related to the its Raman intensities of the corresponding characteristic peak, with a detection limit of 8.7 × 10−9 M. As a result of the testing artificial water samples, the recovery rate ranged from 87.9 % to 117 %. [Display omitted] • We synthesized ferromagnetic nanomaterials suitable for selectively adsorbing DMP. • A linear correction was found between DMP concentrations and Raman intensities. • The material is reusable with adsorption capacity loss of 9.8 % after seven cycles. • The recovery rate ranged from 87.9 % to 117 % for DMP in artificial water samples. To overcome the complicated pretreatment, low selectivity and low sensitivity detection associated with the detection of dimethyl phthalate (DMP), this study synthesized ferromagnetic nanomaterials that coupled with surface enhanced Raman scattering (SERS) and molecular imprinting polymers (MIPs). The pretreatment process can be simplified by ferromagnetic nanomaterials, then Fe 3 O 4 @SiO 2 @Ag@MIPs selectively adsorbing DMP can be achieved, and SERS can be applied for DMP detection with high sensitivity. As a control, the non-imprinted polymers (NIPs) Fe 3 O 4 @SiO 2 @Ag@NIPs were synthesized. Adsorption experiments results showed that the saturation adsorption amounts of Fe 3 O 4 @SiO 2 @Ag@MIPs is 36.74 mg/g with 40 mg/L DMP and Fe 3 O 4 @SiO 2 @Ag@NIPs is 17.45 mg/g. For DMP, Fe 3 O 4 @SiO 2 @Ag@MIPs have a greater affinity. In addition, after seven adsorption-desorption cycles the Fe 3 O 4 @SiO 2 @Ag@MIPs are reusable with approximately a 9.8 % loss in adsorption capacity. With an 8.7 × 10−9 M detection limit, DMP detection was performed by SERS, which revealed that the Raman intensities of the associated characteristic peak were linearly proportional to the DMP concentrations. As a result, the recovery rate of the testing artificial water varied from 87.9 % to 117 %. These outcomes show that the suggested technique for finding DMP in actual water samples is practical. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel molecular imprinted type of biomass carbon MIP @ BC was synthesized; • MIP@BC-mediated electro-Fenton achieved 100 % DMP degradation within 15 min; • The targeted adsorption capacity of MIP@BC provides a possibility for degrading DMP; • MIP@BC has an excellent 2 e− oxygen reduction capacity to favor H 2 O 2 generation; • OH and O 2 − are the key reactive oxygen species mediating the degradation of DMP. A novel molecularly imprinted biomass carbon (MIP@BC) catalyst functionalized with the virtual template of phthalates was designed as the cathode material which possesses excellent 2-electron oxygen reduction ability and H 2 O 2 production capacity, which is suitable for targeted degradation of phthalates in the electro-Fenton system. Following molecularly imprinted modification, the adsorption capacity of MIP@BC for Dimethyl phthalate (DMP) increased by 40 %, reached 9.26 mg/g. Compared with non-imprinted biomass carbon (NIP@BC), the MIP@BC-mediated electro-Fenton process enhanced the degradation rate of DMP by 72 %. Additionally, the degradation rate of DMP rises by 51 % and 104 % respectively on the basis of river water and domestic sewage. The reactive oxygen species that induced DMP degradation were OH and O 2 − and targeted adsorption and catalysis exert a synergistic effect. This study provides a new insight into targeted degradation for high-toxicity of emerging contaminants from complex aqueous environment. [ABSTRACT FROM AUTHOR]

Ophthalmic hydrogels are known for their hydrophilicity, which although beneficial for eye comfort, also predisposes them to absorbing external compounds, including potentially harmful phthalates. This study investigated the absorption of dimethyl phthalate and diethyl phthalate, plasticizers found in numerous consumer products by ophthalmic hydrogels. The results demonstrate differential absorption capacities between the two hydrogels, attributed to their distinct compositions. The interaction between hydrogels and phthalates is found to be predominantly physical, as evidenced by unchanged chemical structures post-absorption. Notably, phthalate absorption alters surface properties, including surface free energy and water content, while oxygen permeability remains unaffected. These findings underscore the complexity of hydrogel-phthalate interactions and the necessity of accounting for environmental pollutants in the design of ophthalmic materials. This research contributes to the development of safer, more environmentally resilient ophthalmic hydrogels, emphasizing the importance of further studies to mitigate the effects of contaminants like phthalates on contact lenses and other ophthalmic devices. [Display omitted] • Ophthalmic hydrogels resist pollutants, like phthalates, crucial for contact lens safety and integrity in various environments. • FT-IR and XRD analyses indicate physical entrapment of phthalates in ophthalmic hydrogels, preserving chemical structures. • Phthalate exposure affects ophthalmic hydrogel properties, potentially impacting eye interactions. [ABSTRACT FROM AUTHOR]

Aim: The objectives of the present study were to explore the benzyl butyl phthalate (BBP) and dimethyl phthalate (DMP) degradation potential of Bacillus marisflavi RR014 isolated from the tap water of public toilet and also to optimize the phthalates degradation process using response surface methodology. Methods and Results: The minimal salt medium was used for the biodegradation analysis of phthalates. The quantification of phthalates and their intermediate metabolites identification were done by using UHPLC and LC‐MS/MS respectively. The results revealed that B. marisflavi RR014 is capable of degrading both the phthalates under varying pH, temperature and salinity conditions. The formation of phthalic acid from the breakdown of BBP and DMP (500 mg l−1) in the medium was observed after 24 h. After 72 h, 61% of BBP and 98·9% of DMP in the medium was degraded as monitored by UHPLC. The identification of intermediate metabolites by LC‐MS/MS revealed that hydrolysis of BBP and DMP produces phthalic acid. Conclusions: The degradation rate of both the phthalates was increased as the parameters increased up to an optimum level. The three environmental factors (pH, temperature and salt concentration) strongly affect the rate of degradation of both the phthalates. The maximum degradation rate for both the phthalates was achieved at pH 7, temperature 35°C and salt concentration of 1% as observed from the central composite experimental design. Significance and Impact of the Study: It is the first report on the phthalates biodegradation potential of B. marisflavi RR014 isolated from the tap water of public toilet. The bacterium is capable of degrading BBP and DMP under varying pH, temperature and salinity, therefore, ideal to treat the phthalate contaminated environments. [ABSTRACT FROM AUTHOR]

Dimethyl phthalate (DMP), used as a plasticizer in industrial products, exists widely in air, water and soil. Staphylococcus aureus is a typical model organism representing Gram-positive bacteria. The molecular mechanisms of DMP toxicology in S. aureus were researched by proteomic and transcriptomic analyses. The results showed that the cell wall, membrane and cell surface characteristics were damaged and the growth was inhibited in S. aureus by DMP. Oxidative stress was induced by DMP in S. aureus. The activities of succinic dehydrogenase (SDH) and ATPase were changed by DMP, which could impact energy metabolism. Based on proteomic and transcriptomic analyses, the oxidative phosphorylation pathway was enhanced and the glycolysis/gluconeogenesis and pentose phosphate pathways were inhibited in S. aureus exposed to DMP. The results of real-time reverse transcription quantitative PCR (RT- q PCR) further confirmed the results of the proteomic and transcriptomic analyses. Lactic acid, pyruvic acid and glucose were reduced by DMP in S. aureus , which suggested that DMP could inhibit energy metabolism. The results indicated that DMP damaged the cell wall and membrane, induced oxidative stress, and inhibited energy metabolism and activation in S. aureus. [Display omitted] [ABSTRACT FROM AUTHOR]

In the present work, we assessed the photocatalytic performance of the new 3-D/3-D Z-scheme heterojunction composite for the degradation of dimethyl phthalate (DMP). The composite was composed by marimo-like Bi2WO6 and mammillaria-like ZnO which was named BWZ. The composite was successfully fabricated using a hydrothermal-precipitation method and analyzed via different characterization techniques. Under natural sunlight irradiation, the optimal composite with 20 wt% of Bi2WO6/ZnO (20-BWZ) exhibited a photodegradation rate constant of 0.0259 min−1, which reached 2.3 and 5.9-folds greater than those of pure ZnO (0.0112 min−1) and Bi2WO6 (0.0044 min−1), respectively. That was predominantly attributed to the formation of a Z-scheme photocatalytic system in the as-synthesized composite reduced the charge carrier recombination and accelerated the photoactivity. Transient photocurrent response and electrochemical impedance spectroscopy analyses were performed to confirm this conclusion. The reusability test indicated that the 20-BWZ had no significant deactivation after four runs, which inferred good stability of the as-prepared composite. Furthermore, the quenching test demonstrated that the photogenerated hole, superoxide anion radical and hydroxyl radical were all involved in the photodegradation of DMP, among which •OH was the principal reactive species. This work revealed that the as-prepared BWZ composites have great potential applications for the degradation of refractory pollutants in the environmental remediation field.

In order to solve the problem of environmental health hazards caused by phthalate esters, a series of pure Bi2O2CO3 and light (La, Ce, Pr, Nd, Sm and Eu) and heavy (Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) rare earth-doped Bi2O2CO3 samples were prepared by hydrothermal method. The crystalline phase composition and physical structure of the samples calcined at 300 °C were studied, and we found that the rare earth ion doping promoted the transformation of Bi2O2CO3 to β-Bi2O3 crystalline phase, thus obtaining a mixed crystal phase photocatalyst constituted by rare earth-ion-doped Bi2O2CO3/β-Bi2O3. The Bi2O3/Bi2O2CO3 heterostructure had a lower band gap and more efficient charge transfer. The fabricated samples were applied to the photocatalytic degradation of dimethyl phthalate (DMP) under a 300 W tungsten lamp, and it was found that the rare earth ion doping enhanced the photocatalytic degradation activity of DMP, in which the heavy rare earth of Er-doped sample reached 78% degradation for DMP at 150 min of light illumination. In addition, the doping of rare earths resulted in a larger specific surface area and a stronger absorption of visible light. At the same time, the formation of Bi2O2CO3/β-Bi2O3 heterogeneous junction enhanced the separation efficiency of photogenerated electrons and holes.

In the current study, an integrated physiochemical method was utilized to remove tonalide (TND) and dimethyl phthalate (DMP) (as emerging contaminants, ECs), and nickel (Ni) and lead (Pb) (as heavy metals), from synthetic wastewater. In the first step of the study, pH, current (mA/cm2), and voltage (V) were set to 7.0, 30, and 9, respectively; then the removal of TND, DMP, Ni, and Pb with an electro-ozonation reactor was optimized using response surface methodology (RSM). At the optimum reaction time (58.1 min), ozone dosage (9.4 mg L−1), initial concentration of ECs (0.98 mg L−1), and initial concentration of heavy metals (28.9 mg L−1), the percentages of TND, DMP, Ni, and Pb removal were 77.0%, 84.5%, 59.2%, and 58.2%, respectively. For the electro-ozonation reactor, the ozone consumption (OC) ranged from 1.1 kg to 3.9 kg (kg O3/kg Ecs), and the specific energy consumption (SEC) was 6.95 (kWh kg−1). After treatment with the optimum electro-ozonation parameters, the synthetic wastewater was transferred to a fixed-bed column, which was filled with a new composite adsorbent (named BBCEC), as the second step of the study. BBCEC improved the efficacy of the removal of TND, DMP, Ni, and Pb to more than 92%.

Dimethyl phthalate (DMP) is widely used as plasticizer, and this kind of plastic industry wastewater is refractory due to the complex chemical structure and endocrine disrupting property. In order to effectively degrade and mineralize DMP contaminated wastewater, a heterogeneous UVC/VUV-Fenton catalyst system was designed with the amendment of targeted design catalyst Fe 3 O 4 @CM-β-CD/rGO with core-shell like structure covered with loose convex folded lamellar. The optimum removal and mineralization efficiency of DMP were 98.6 % and 62.8 % in 30 min with 150 mg L−1 Fe 3 O 4 @CM-β-CD/rGO and 8 mmol L−1 H 2 O 2. This efficient and fast removal were attributed to a variety of photocatalytic oxidative active species •OH, •O 2 − and h+ with 59.6%, 29.1% and 9.9% contribution ratio, which mainly took effect on benzene ring open and side-chain fracture by oxidative, hydrolysis and hydrogen substitution determined by the rupture energy requirement from chemical bond in DMP. The target function of CM-β-CD in catalyst controlled the photo-electron generation rate and shorten mass transfer distance by the cladding lamellar, moreover, rGO accelerated the redox between Fe (II) and Fe (III) and electron transfer. The catalytic recovery and removal to DMP kept above 90 % after five recycles. This study provided an excellent performance catalyst and an effective photo-Fenton approach and for the treatment of endocrine disrupting wastewater. [Display omitted] • Nano catalysts Fe 3 O 4 coated by cross-linked lamellar CM-β-CD/rGO was prepared. • Removal efficiency and mineralization of DMP were 98.6% and 62.8% in 30min. • The.•OH, •O 2 −, and h+ contributed to 59.6%, 29.1% and 9.9% DMP removal. • DMP degnuradation pathways mediated by chemical structure and bond energy. • Catalytic recovery and DMP removal efficiency kept above 90 % after five recycles. [ABSTRACT FROM AUTHOR]

• Co single atom-doped two-dimensional nanocatalysts were prepared by soft stencil method. • The two-electron oxygen reduction proformation of the material are effectively improved by Co metal. • Co@NSC has excellent degradation efficiency and TOC removal rate under medium and alkaline conditions. • The degradation pathway and intermediate products of DMP are reasonably evaluated. Electro-Fenton technology is an advanced oxidation process for phthalic acid esters (PAEs) that builds upon traditional Fenton technology, enhancing its efficiency, selectivity, and flexibility. Thus, cobalt-doped carbon-based catalyst (Co@NSC) were prapered via melamine doped by cobalt (Co) and calcinated at high temperature, and showed excent mesoporous structure (mainly range from 1.3 to 16 nm), high surface area (223.26 m2/g) and big pore volume (0.392 cm3/g). And the result of electrochemical performance test showed that the two-electron oxygen reduction ability of the material can be effectively improved in the case of Co doping. DMP can be degraded within 30 min by using Co@NSC as an electro-Fenton cathode, with excellent degradation efficiency (100 %) and total organic carbon (TOC) mineralization rate (about 40 %) even under the optimal conditions. The exploration of the mechanism demonstrated that OH and 1O 2 were the main contributors. According to density functional theory (DFT) theoretical calculation and liquid chromatograph-mass spectrometer(LC-MS) results, the vulnerable site and degradation path of DMP were reasonably speculated. The ecotoxicity evaluation of the degradation products showed that the the toxicity of DMP has been significantly reduced during degradation process by Co@NSC electro-Fenton. Thus, Co@NSC is a cost-effective and promising catalyst, in which all the metal sites were utilized while the cost of metal were significantly minimized. [ABSTRACT FROM AUTHOR]

Fenton oxidation technology is a widely-used advanced oxidation technology. However, the generation of hydroxyl radicals is restrained by the sluggish recovery of Fe(II), thus affecting its long-lasting performance for water decontamination. Here, a novel niobium carbide (Nb 2 C) MXene material was applied as a green co-catalyst. Nb 2 C MXene can significantly promote Fenton reactions to produce hydroxyl radicals for degrading dimethyl phthalate (DMP) with high efficiency and high stability for long-term operation, which outperforms than various reported co-catalysts. Meanwhile, the Nb 2 C/Fe(III)/H 2 O 2 system is capable of non-selectively degrading a wide spectrum of refractory pollutants. Mechanism investigation reveals that Nb 2 C MXene as an electron donor can straight reduce Fe(III), meanwhile mediate electron shuttle from Fe(II) to H 2 O 2 to strongly expedite the generation of hydroxyl radicals. In addition, four main degradation routes of DMP were proposed. Therefore, this study offers an updated and valid strategy for the refractory organic pollutants elimination by coupling Nb 2 C MXene and Fenton oxidation. [Display omitted] • Nb 2 C MXene outperformed than a variety of co-catalysts of enhanced Fenton system. • The Nb 2 C/Fe(III)/H 2 O 2 can non-selectively degrade a wide spectrum of organic contaminants. • Nb 2 C MXene can provide electrons for direct Fe(III) reduction by cleaving Nb-C bonds. • Nb 2 C MXene can mediate electron transfer between Fe(II) and H 2 O 2 to promote Fenton reaction. [ABSTRACT FROM AUTHOR]

Large quantities of phthalic acid esters (PAEs) are released and migrate into the environment continuously and become ubiquitous in soil, surface water, groundwater and other areas, eventually leading to serious environmental pollution. Therefore, the methods of PAEs mineralization have become a hot research topic. In this study, a highly efficient dimethyl phthalate (DMP)-degrading bacterium capable of utilizing DMP as the sole source of carbon and energy was isolated from frozen soil collected from a refuse disposal station. The DMP-degrading bacterium was identified as Pseudomonas sp. QDF12 according to the phylogeny of 16S rDNA sequence. The degradation process well fitted a first-order kinetic model, with a half-life of 9.8 h and the highest degradation rate of 20.19 mg/L•h at 15.0 °C. The fermentation conditions that enhanced the fermentation of biomass were optimized via Plackett-Burman design and response surface methodology. Finally, the carbon-nitrogen ratio, CaCO3, temperature and shaking speed were identified as key factors. Verification experiments indicated that the maximal biomass was 1.85 × 109 cfu/mL under the optimized conditions, which was 134.18% and 66.67% higher than those obtained under the Luria broth medium and the basic fermentation conditions, respectively. The time and temperature of fermentation were reduced to 12 h and 12.0 °C respectively. In conclusion, the strain QDF12 is more suitable for application in low-temperature areas owing to its fast, efficient fermentation and low-temperature resistance. Because of the shorter fermentation period and lower fermentation temperature, the large-scale commercial application of strain QDF12 will reduce the production costs and accelerate the fermentation speed.

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A series of novel 2-(oxazolo[5,4-b]pyridin-2-yl)-N-phenylbenzamide derivatives have been prepared by one-pot three-component synthesis using 2-aminopyridin-3-ol, dimethyl phthalate, and anilines in 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]BF4) at 80–85°C for 90–120 min. This method offers remarkable advantages of good yields, straightforward protocol, environmental friendliness, short reaction times, and mild reaction conditions. The need in catalysts and solvents is avoided by using a catalytically active ionic liquid as a medium. [ABSTRACT FROM AUTHOR]

Background and purpose: Phthalic acid esters (PAEs) are a group of organic compounds that are used as additives in plastic industry. Among PAEs, dimethyl phthalate (DMP), the simplest compound in phthalates, is an aromatic pollutant that disturbs endocrine function. The aim of this study was to assess the effect of zero-valent iron nanoparticles (NZVI) on the DMP degradation. Materials and methods: NZVI were prepared by reduction of ferric chloride using sodium borohydride. Physical properties of nanoparticles were determined using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD), and Vibrating Sample Magnetometer (VSM). Then, the effect of pH, DMP concentrations, the amount of NZVI, and contact time were investigated on DMP removal efficiency. Response surface methodology based on Box-Behnken was used to study the interaction between variables. Results: Maximum efficiency (99%) of DMP removal by NZVI was achieved in optimum conditions (pH=3, NZVI dosage =0.6 g/l, DMP concentration = 2 mg/l, and contact time= 65 min). The Box-Behnken analysis confirmed that pH and NZVI dosage have had the highest and lowest effect in the process of DMP removal by NZVI, respectively. Conclusion: According to findings, NZVI in small amounts have a proper efficiency in DMP removal. Also, DMP degradation efficiency did not change much, after being used in five consecutive cycles of degradation reactions. This shows a potential application prospect of the synthesized NZVI in real water treatment.

Introduction. There have been no studies, monitoring programs, or data about phthalate levels made available to the public on the safety of residential drinking water in Lagos, Nigeria. Objectives. The present study aimed to assess the concentrations of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), and zinc (Zn), lead (Pb), chromium (Cr), and cadmium (Cd) in drinking water drawn from taps in three residential areas of the state. Methods. High performance liquid chromatography and atomic absorption spectroscopy were used to determine the concentrations of phthalates and metals, respectively. Results. All of the water samples collected throughout the sampling period contained DMP, while DEP and DBP were present in only some of the samples. The highest mean DMP, DEP, and DBP concentrations of 1.15±0.28 mg/l, 0.09±0.16 mg/l, and 0.28±0.33 mg/l, respectively, were found in water samples collected from Lagos Street (Ebute-metta East). In addition, the trace/toxic metal concentrations in the water samples were found to be low for Cr, but high for Cd, Pb, and Zn, especially when compared with World Health Organization (WHO) limit values for drinking water. Lead recorded the highest mean concentration of 0.087±0.021 mg/l in the water samples obtained from Apapa Road (Ebute-Metta West). In the same vein, the highest significant (P < 0.01) mean Cr concentration of 0.047±0.012 mg/l was found in the water samples obtained from Apapa Road (Ebute-Metta West). Conclusions. In view of the high concentrations of phthalates and metals in the water sampled in this study, and the potential adverse health effects of these contaminants, especially on children and women of child-bearing age, the Lagos State Government of Nigeria and the state water corporation are called upon to immediately institute a monitoring program to identify the sources of contaminants and take appropriate intervention measures. Competing Interests. The authors declare no competing financial interests.

A CuCr-layered double hydroxide nanosheet intercalated with terephthalic acid (TPA/LDH) was introduced as a coating for the in-tube solid phase microextraction (IT-SPME). The coating was placed on the inner surface of a stainless steel tube by using two-electrode electrodeposition. The sorbent was characterized by X-ray diffraction, scanning electronic microscopy, and Fourier transform infrared spectroscopy. The TPA/LDH coating, compared to a nitrate-LDH coating, exhibits enhanced extraction efficiency, long lifetime, good mechanical stability, and a large specific surface. The method was used for the extraction, preconcentration, and subsequent HPLC-based determination of dimethyl phthalate (DMP), dibutyl phthalate (DBP), diallyl phthalate (DAP), and diethylhexyl phthalate (DEHP). The effects of pH value of the solution, salt concentration, extraction and desorption conditions, and the effect of the alcohol content of the solution on the extraction efficiency were optimized. Under optimal conditions, the response is linear in the 0.05 to 1000 μg L−1 ester concentration range, and the limits of detection (at S/N = 3) range between 0.01 to 0.1 μg L−1. The inter- and intra-assay precisions (RSD%, for n = 3) range from 3.8 to 6.8% and from 3.5 to 5.7%, respectively. The method was successfully applied to the determination of four phthalate esters in different beverage samples. [ABSTRACT FROM AUTHOR]

Large quantities of phthalic acid esters (PAEs) are released and migrate into the environment continuously and become ubiquitous in soil, surface water, groundwater and other areas, eventually leading to serious environmental pollution. Therefore, the methods of PAEs mineralization have become a hot research topic. In this study, a highly efficient dimethyl phthalate (DMP)-degrading bacterium capable of utilizing DMP as the sole source of carbon and energy was isolated from frozen soil collected from a refuse disposal station. The DMP-degrading bacterium was identified as Pseudomonas sp. QDF12 according to the phylogeny of 16S rDNA sequence. The degradation process well fitted a first-order kinetic model, with a half-life of 9.8 h and the highest degradation rate of 20.19 mg/L•h at 15.0 °C. The fermentation conditions that enhanced the fermentation of biomass were optimized via Plackett-Burman design and response surface methodology. Finally, the carbon-nitrogen ratio, CaCO3, temperature and shaking speed were identified as key factors. Verification experiments indicated that the maximal biomass was 1.85 × 109 cfu/mL under the optimized conditions, which was 134.18% and 66.67% higher than those obtained under the Luria broth medium and the basic fermentation conditions, respectively. The time and temperature of fermentation were reduced to 12 h and 12.0 °C respectively. In conclusion, the strain QDF12 is more suitable for application in low-temperature areas owing to its fast, efficient fermentation and low-temperature resistance. Because of the shorter fermentation period and lower fermentation temperature, the large-scale commercial application of strain QDF12 will reduce the production costs and accelerate the fermentation speed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the study, the effects of dimethyl phthalate (DMP) on the antioxidant defense capacity and immune functions of human erythrocytes were experimentally explored. DMP affected the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) and the contents of glutathione (GSH) and malondialdehyde (MDA) in erythrocytes, thus impairing the function of antioxidant defense system of erythrocytes. When DMP concentration increased from 0 to 28 μmol L−1, the SOD and GPX activities were increased firstly and then gradually decreased. When DMP concentration was below 20 μmol L−1, the relative activity of SOD was enhanced by DMP and the effect was known as hormesis. The relative activity of GPX was also increased when the concentration of DMP was below 12 μmol L−1. The CAT activity was more significantly inhibited by DMP than the activities of SOD and GPX, whereas the relative GSH content was increased by DMP. MDA levels were significantly changed after the exposure to DMP (0–24 μmol L−1). The experimental results of the activity of SOD and CAT, and the content of MDA also suggested that DMP could inhibit the immune functions of red blood cells (RBCs), which were further proved by the decrease of two indicators (RBC-C 3 b and RBC-IC) due to the destruction of C 3 b receptor with immune adherence function on erythrocyte membrane. The study provides a deep understanding of the toxicity of DMP on erythrocytes. Image 1 • The effects of DMP on the antioxidant defense capacity and immune functions of human erythrocytes were explored. • DMP impaired the function of erythrocyte antioxidant defense system (activities of SOD, CAT, GPX; contents of GSH, MDA). • DMP decreased the immune functions of erythrocytes, as proved by the decrease of two indicators (RBC-C 3 b and RBC-IC). DMP could decrease the antioxidant defense capacity, lead to the oxidative stress, and impair the immune function of erythrocytes. This study provides the basis for exploring the toxicity of PAEs in blood. [ABSTRACT FROM AUTHOR]