Frontiers in Environmental Science
·
2023
·
IF 4.6
Gu Yurong,Zhang Yi,Jiang Chengchun,Dong Zijun,Bai Xue
UV/sulfite process without oxygen has been extensively explored and used for the degradation of many micro-pollutants. In the present work, a UV/sulfite process in the presence of oxygen was applied to degrade a widely used pharmaceutical compound, metformin (MET). The results showed that the oxygen-involved UV/sulfite process could efficiently degrade MET. At an initial concentration of 2.5 mg/L, 86.0% of MET was removed from the contaminated water within 180 min irradiation at a sulfite dosage of 10 mM, solution pH of 9, and UV intensity of 4,092 μW/cm2. In addition, sulfate radical (SO4•-), hydroxide radical (•OH), hydrogen atom (•H), and hydrated electron (eaq−) were found to be the dominant active species contributing to MET removal in the studied process through scavenging experiments. The increase in UV intensity, sulfite dosage, solution pH, and reaction temperature enhanced MET degradation in the investigated process to a certain extent, whereas the introduction of bicarbonate and fulvic acid slightly suppressed MET degradation. Finally, the degradation products of MET were identified. The oxygen-involved UV/sulfite process exhibited a remarkable denitrification capacity (>80%) in MET. The findings of this study may offer a novel approach for treating emerging contaminants.
研究领域:
环境科学
·
药学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Jianwei Wang,Yanguo Teng,Caixiang Zhang,Xiaoping Liao,Yuanzheng Zhai,Rui Zuo
Organophosphorus pesticides (OPPs), a kind of effective insecticide, have attracted extensive attention of researchers because of the high toxicity and refractory character of their degradation products . Given the ubiquity of manganese dioxide (MnO 2 ) and bisulfite (HSO 3 − ) in environmental media, the abiotic degradation of several typical OPPs by the MnO 2 -HSO 3 - reaction system was investigated in batch experiments. As a representative OPP, methyl parathion (MP) was chosen to be the focus of the study. The removal rate of MP was remarkably improved by adding bisulfite (HSO 3 − ) to the MnO 2 single-reaction system, and the oxidation product methyl paraoxon was below the detection limit. The primary active substances generated from the reaction system were determined to be Mn(III) species by adding excess radical scavengers or complexants (methanol and pyrophosphate) to the reaction system. On the basis of the metabolic products of MP identified by liquid chromatography–high-resolution mass spectrometry (LC/HRMS) and gas chromatography–mass spectrometry (GC/MS), the transformation pathway of MP in the MnO 2 -HSO 3 - reaction system was elicited, which included the predominant processes of hydrolysis and oxidation. Furthermore, the typical OPPs with different structures were also degraded efficiently by the reaction system because of the oxidative degradation of Mn(III). This study offers significative information related to the abiotic oxidation of manganese minerals and the fate and dissipation of OPPs in the actual environment.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2024
·
IF 8.1
Guowen Tang,Yuling Chen,Shanshan Lin,Xiaolin Li
Sulfadoxine (SDX) is a broad-spectrum veterinary antibiotic, which was used alone for the treatment of various infections in the past, and detected ubiquitously in the aqueous environment. However, understanding SDX's photo- and microbial degradation within the environment, especially in marine matrixes, remains limited. This research hones in on SDX's degradation dynamics in seawater. Photodegradation emerges as the dominant process, surpassing microbial degradation in speed and efficiency. Notably, 90% of SDX is photo-degraded within 12 h, while only 52% is removed via microbial degradation over two weeks. Time-of-flight mass spectrometry provides high-resolution molecular mass information on degradation products . The molecular structures of hydrolysis, photo-, and microbial degradation products are deduced from accurate precursor and fragment ion masses, alongside an integrated data processing workflow. Six hydrolysis products arise from the treatment, and photodegradation and microbial degradation yield nine and eighteen products, respectively. Molecular insights from these products inform plausible degradation pathways involving hydrolysis, photodegradation, and microbial degradation. Processes like bond cleavage, methylation , hydroxylation, oxidation, reduction, and methoxylation are identified and associated with degradation. This study presents a comprehensive workflow for acquiring and processing degradation product data linked to emerging organic pollutants. Moreover, it contributes to our comprehension of the environmental fate of veterinary drugs in marine ecosystems .
研究领域:
环境科学
·
药理学
✓ 已验证
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2025
·
IF 8
Zhengfeng Guo,Tingting Zhang,Hao Yang,Xiaolin Zhu,Siyuan Lu,Anjie Chen,Mingyu Fan,Jiao Qu
In aquatic environments, antibiotics degrade into byproducts, potentially enhancing bacterial resistance. However, the specific mechanisms by which these byproducts induce bacterial resistance remain elusive. This study conducted experimental evolution experiments to explore how E. coli adapts to tetracycline (TC) and its primary degradation products—anhydrotetracycline (ATC), epitetracycline (ETC), and 4-epianhydrotetracycline (EATC)—through evolution experiments. Prolonged exposure to TC and its byproducts significantly increased frequency of resistant mutants in E. coli ATCC25922, with a maximum 10 6 -fold increase. Resistant mutants exhibited markedly elevated minimum inhibitory concentrations (MICs) for TC, ampicillin (AMP), and ciprofloxacin (CIP), indicating multidrug resistance. Transcriptomic analysis showed that the antibiotic resistance phenotype could be related to enhanced target protection, metabolic adaptations, and reduced membrane permeability. The induction pathways between TC and its byproducts were distinct. Specifically, TC 20d (where TC 20d represents the mutants collected after 20 days of continuous exposure to TC) was associated with more alterations in ribosome-associated genes, which was correlated with an enhanced defensive response as shown by the data. Moreover, variations in energy metabolism gene expression suggest a robust metabolic defense in ATC 20d and ETC 20d . When TC and its byproducts—ATC, ETC, and EATC—act together, they induce antibiotic resistant mutants at rates of 29.8 %, 18.9 %, 18.3 %, and 31.9 %, respectively. This study provides a descriptive overview of the possible adaptive mechanisms and pathways that may be involved in antibiotic resistance due to environmental exposure.
研究领域:
微生物学
·
环境科学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Wulve Fan,Zhiliang Zhu,Xiaochang Liu,Hua Zhang,Yanling Qiu,Daqiang Yin
Nitrogen oxides and sulfur oxides , as the dominant toxic gases in the atmosphere, can induce severe human health problems under the composite pollutant conditions. Currently the effect of nitrogen or sulfur oxides in atmospheric environment to the degradation and cytotoxicity of triphenyl phosphate (TPhP) on atmospheric particle surfaces still remain poorly understood. Hence, laboratory simulation methods were used in this study to investigate the effect and related mechanism. First, particle samples were prepared with the TPhP coated on MnSO 4 , CuSO 4 , FeSO 4 and Fe 2 (SO 4 ) 3 surface. The results showed that, when nitrogen or sulfur oxides were present, more significant TPhP degradation on all samples can be observed under both light and dark conditions. The results proved nitrogen oxides and sulfur oxides were the vital influence factors to the degradation of TPhP, which mainly promoted the OH generation in the polluted atmosphere. The mechanism study indicated that diphenyl hydrogen phosphate (DPhP) and OH-DPhP were two main stable degradation products . These degradation products originated from the phenoxy bond cleavage and hydroxylation of TPhP caused by hydroxyl radicals . In addition, no TPhP related organosulfates (OSs) or organic nitrates (ON) formation were observed. Regarding the cytotoxicity, all the particles can induce more significant cellular injury and apoptosis of A549 cells , which may be relevant to the adsorbed nitrogen oxides or sulfur oxides on particles surfaces. The superfluous reactive oxygen species (ROS) generation was the possible reason of cytotoxicity. This research can supply a comprehensive understanding of the promoting effect of nitrogen and sulfur oxides to TPhP degradation and the composite cytotoxicity of atmospheric particles.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Natural Product Communications
·
2024
·
IF 1.5
Meng S. Cheong,Lutfun Nahar,Satyajit D. Sarker,Hui Cao,Wai S. Cheang,Jianbo Xiao
Piceatannol is a stilbenoid, which has shown bioactivities in various cell culture models. However, its stability in cell culture medium is not clear. Here, UPLC-MS/MS was applied in situ to analyze the degradation products of piceatannol in Dulbecco's Modified Eagle's Medium (DMEM) and cell culture to investigate the compound's stability in DMEM. During the incubation with cell culture medium (at 4 and 37 °C), several piceatannol derivatives, such as an oxidation product (m/z 243.06), a reduction product (m/z 247.09), dimers (m/z 485.12 and 487.14) and trimers (m/z 727.18) were detected, which demonstrated the instability of piceatannol in cell culture conditions. To confirm if the new products during the incubation were generated due to the instability of piceatannol, ascorbic acid was added. The presence of ascorbic acid could significantly slow the degradation rate of piceatannol and the generation of piceatannol derivatives, which proved that the new products were generated by the degradation of piceatannol and indicated that the instability of piceatannol might be related to its antioxidant activity.
研究领域:
生物化学
·
药物化学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2018
·
IF 3.927
Hao Ling,Sen Liu,Hongxia Gao,Zhiwu Liang
In order to study the effect of heat-stable salts (HSSs) on the CO 2 absorption performance of amine solution, the CO 2 absorption/desorption rates and cyclic CO 2 capacity of 30 wt% (monoethanolamine) MEA solutions in the presence of various acidic degradation products were comprehensively investigated systematically by an improved rate-based screening method. In addition, the initial pH values and CO 2 equilibrium solubility were also evaluated. These acidic degradation products considered were formic acid , acetic acid, propionic acid , butyric acid , glycolic acid, oxalic acid , lactic acid, malonic acid and bicine. The experimental results indicated that the carboxylic acids with different chemical structures can reduce the initial pH values, equilibrium solubility of CO 2 , absorption rate and cyclic CO 2 solubility, but promote the CO 2 desorption rate of aqueous MEA solution. Furthermore, a countermeasure was proposed to maintain absorption performance and reduce the energy requirement of solvent regeneration for an MEA amine-treating unit. The obtained results can provide a guidance for developing corresponding countermeasure for heat-stable salts control and removal in the CO 2 absorption-stripping process using amine solutions.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2011
·
IF 3.723
Hua Chen,Hanjin Luo,Yuecun Lan,Tingting Dong,Bingjie Hu,Yiping Wang
The interactions of tetracycline (TC) with nanoscale zerovalent iron (NZVI) modified by polyvinylpyrrolidone (PVP-K30) were investigated using batch experiments as a function of reactant concentration, pH, temperature, and competitive anions. Transmission electron micrographs (TEM), BET surface area and Zeta (ζ)-potential analyses indicated that the mean particle size was 10–40 nm with a surface area of 36.90 m 2 /g, and a iso-electric point of PVP-NZVI was 7.2. The results of X-ray diffraction (XRD) and high-resolution X-ray photoelectron spectroscopy (HR-XPS) of modified nanoscale zerovalent iron (PVP-NZVI) revealed that the iron nanoparticles likely have a core of zero-valent iron (Fe 0 ), while a shell is largely made of iron oxides . Degradation of TC was strongly dependent on pH and temperature. The presence of silicate and phosphate strongly inhibited the removal of TC, whereas acetate and sulfate only caused slight inhibition. LC–MS analysis of the treated solution showed that the degradation products from TC resulted from the removal of functional groups from the TC ring. The degradation products were detected both in the treated solution (initial pH of 3.0 and 6.5) and on the surface of PVP-NZVI after 4-h interaction, indicating that PVP-NZVI can adsorb both TC and its degradation products.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Xiyang Liu,Fei Huang,Yang Yu,Yongan Jiang,Kun Zhao,Yide He,Yanhua Xu,Yongjun Zhang
Sulfamethazine (SMZ), a kind of sulfonamide antibiotics, can exist for a long periods of time and has been widely detected in the environment, which could pose a potential health threat to human beings. In this study, sludge-derived carbon (SC) catalyst was modified and applied to degrade SMZ during catalytic oxidation process. Degradation products and possible transformation pathways were investigated based on data of GC–MS. The toxicity evolution of SMZ degradation after catalytic oxidation process was tested with zebrafish and microbial degradation respirometer . As a consequence, SC modified with nitric acid (SC HNO 3 ) exhibited highly catalytic efficiency reached 92.2% SMZ conversion and 75.2% total organic carbon (TOC) removal rate after 480 min. Ten kinds of possible products were identified by GC–MS during degradation process of SMZ, indicating two possible pathways. No pronounced malformation was observed in the toxicity experiments with zebrafish until 120 h post fertilization (hpf). However, further analysis showed that zebrafish incubated with SMZ solution had higher mortality, lower hatching rate, slower spontaneous movement and shorter body length, compared with the group used normal nutrient solution, while the water after treatment had lower toxicity effects on zebrafish. The toxicity experiments with microbial degradation respirometer showed that SMZ solution had lower value of oxygen uptake, which indicated that SMZ solution had higher values of toxicity and inhibition of pharmaceutical compounds. This study provides a catalyst with low cost and high catalytic efficiency for degradation process of SMZ and gives a deeper insight into the ecotoxicity of treated water.
研究领域:
环境科学
·
毒理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2020
·
IF 4.872
Xiaohua Jiang,Dean Song,Dabin Wang,Ruiming Zhang,Qiannan Fang,Huiqing Sun,Fanyu Kong
Imidacloprid is a widely used neonicotinoid insecticide worldwide, and has attracted great concerns due to its potential threat to human and environment. Much effort was thus spent on developing the effective way for removing imidacloprid from water, but might also produce various degradation products with unknown risks. The hypothesis was then proposed that permanganate oxidation was probably the appropriate tool for eliminating imidacloprid and its toxicity through selective oxidation of specific groups. To that end, we studied the kinetics of permanganate/imidacloprid reaction by considering the effects of pH (5.0–9.0), temperature (15–35 °C), ionization strength (0.05–0.20 M), typical anions (Cl − , Br − , I − ) and humic acid . Based on the identified products from mass spectrometer , the main reaction pathway was found to be the hydroxylation of C–H bond at imidazole ring, leading to the decreased toxicity evaluated by ECOSAR program. Our results demonstrate that permanganate oxidation should be a very promising technique for controlling imidacloprid contamination by effective detoxification through highly selective partial oxidation. Moreover, this study has also paved the way toward applying permanganate oxidation for in situ chemical remediation of imidacloprid, though the corresponding standards need to be established in advance.
研究领域:
环境科学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
Microorganisms
·
2022
·Vol. 10
·期 3
·565
·
IF 4.926
Hao Tan,Delong Kong,Qingyun Ma,Qingqing Li,Yiqing Zhou,Xu Jiang,Zhiye Wang,Rebecca E. Parales,Zhiyong Ruan
In this study, theCutaneotrichosporon dermatisstrain M503 was isolated and could efficiently degrade tetracycline, doxycycline, and chlorotetracyline. The characteristics of tetracycline degradation were investigated under a broad range of cultural conditions. Response surface methodology (RSM) predicted that the highest degradation rate of tetracycline could be obtained under the following conditions: 39.69 °C, pH of 8.79, and inoculum dose of 4.0% (v/v, ~3.5 × 106cells/mL in the medium). In accordance with the five identified degradation products of tetracycline, two putative degradation pathways, which included the shedding of methyl and amino groups, were proposed. Moreover, the well diffusion method showed that the strain of M503 decreases the antibacterial potency of tetracycline, doxycycline, and chlorotetracycline. These findings proposed a putative mechanism of tetracycline degradation by a fungus strain and contributed to the estimation of the fate of tetracycline in the aquatic environment.Keywords:tetracycline;biodegradation;Cutaneotrichosporon dermatis;response surface methodology (RSM);degradation products;antibacterial potency
研究领域:
环境科学
·
微生物学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2015
·
IF 3.352
Jingying Pan,Jie Fu,Shuguang Deng,Xiuyang Lu
A study on extraction of 15 kinds of possible lignin degradation products from aqueous solutions was performed by evaluating the distribution coefficients of five different organic-H 2 O systems under different conditions. The experimental results show that the extraction of lignin degradation products from aqueous solutions achieved equilibrium within 30 min; the concentration of the extracted materials and the amount of extractant had a negligible effect on the distribution coefficients. Among the five kinds of extractants investigated in this work, n-butanol was the best solvent for extracting the lignin degradation products, and chloroform had a good selectivity for the extraction of aldehyde. The temperature greatly influenced the distribution coefficients because the distribution coefficients decreased considerably with the extraction temperature. These results provide insights for the degradation of the lignin in a two-phase system.
研究领域:
化学工程
·
生物化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）