Objective To investigate the application of BPDE-albumin adducts as monitoring biomarkers for coke oven workers exposed to polycyclic aromatic hydrocarbons （PAHs） and to explore possible relationship between BPDE-al...Objective To investigate the application of BPDE-albumin adducts as monitoring biomarkers for coke oven workers exposed to polycyclic aromatic hydrocarbons （PAHs） and to explore possible relationship between BPDE-albumin adducts and urinary 1-hydroxypyrene （1-OHP） levels in them. Methods Thirty-seven coke oven workers from a coke plant and 47 controls without the occupational exposure to PAHs were recruited in this study. The levels of plasma BPDE-albumin adducts and urinary 1-OHP were analyzed using high performance liquid chromatography. Results The median levels of BPDE-albumin adducts （42.10 fmol/mg albumin） and urinary 1-OHP （5.46 μmol/mol creatinine） were significantly higher in coke oven workers than in controls （14.16 fmol/mg albumin, 2.96μmol/mol creatinine, respectively; P〈0.01）. Multiple logistic regression analysis showed that coke oven workers were at higher risk of having BPDE-albumin adduct levels above 25.30 μmol/mg albumin （OR=1.79, P〈0.01） and urinary 1-OHP levels above 4.13 μmol/mol creatinine （OR=2.45, P〈0.05）. There was a positive correlation between the levels of BPDE-albumin adducts and urinary 1-OHP in all subjects （rs=0.349, P〈0.01）. Conclusion BPDE-albumin adduct is a useful biomarker for monitoring long-term exposure to PAHs, and plasma BPDE-albumin adducts level is significantly correlated to urinary 1-OHP levels in coke oven workers.展开更多
Benzo[a]pyrene(B[a]P)is a carcinogenic environmental pollutant widely present in the environment and can enter the human body through the food chain.It is therefore essential to treat and remediate the B[a]P-contamina...Benzo[a]pyrene(B[a]P)is a carcinogenic environmental pollutant widely present in the environment and can enter the human body through the food chain.It is therefore essential to treat and remediate the B[a]P-contaminated environment.Microbial remediation of B[a]Pcontaminated environments is considered to be one of the most effective strategies,and the addition of biostimulants is a feasible method to further improve the effectiveness of microbial remediation.In this study,we used Bacillus subtilis MSC4 to screen for the stimulation of sodium gluconate,which promoted B[a]P degradation.Based on biochemical and transcriptomic analyses,Sodium gluconate was found to significantly increase the biomass of MSC4 and the expression of most genes involved in B[a]P degradation.Activities of central carbon metabolism,fatty acidβ-oxidation and oxidative phosphorylation were all promoted.The significant increase in acid-induced oxalate decarboxylase expression indicates a decrease in intracellular pH,which promoted the synthesis of acetoin and lactate.Genes involved in the nitrogen cycle,especially nitrification and denitrification,were significantly up-regulated,contributing to B[a]P degradation.Genes involved in the synthesis of enzyme cofactors,including thiamine,molybdenum cofactors,NAD and heme,were up-regulated,which contributes to increasing enzyme activity in metabolic pathways.Up-regulation of genes in flagella assembly,chemotaxis,and lipopeptide synthesis is beneficial for the dissolution and uptake of B[a]P.Genes related to the sugar transport system were upregulated,which facilitates the transport and absorption of monosaccharides and oligosaccharides by MSC4.This study provides a theoretical basis for the further application of sodium gluconate in the treatment of PAH-contaminated sites.展开更多
Six coordination polymers based on 9,10-di(pyridine-4-yl)-anthracene(DPA)and 1,6-di(1H-imidazol-1-yl)pyrene(DIP)were obtained by solvothermal reactions.{[Zn(DPA)Cl_(2)]·DMF·2H_(2)O}n(1)and{[Zn_(1.5)(DPA)_(1....Six coordination polymers based on 9,10-di(pyridine-4-yl)-anthracene(DPA)and 1,6-di(1H-imidazol-1-yl)pyrene(DIP)were obtained by solvothermal reactions.{[Zn(DPA)Cl_(2)]·DMF·2H_(2)O}n(1)and{[Zn_(1.5)(DPA)_(1.5)Cl_(3)]·5H_(2)O}n(2)are framework isomers,which both contain zigzag chains formed by DPA,Zn^(2+),and Cl-.The zigzag chains in 1 are further assembled by C—H…Cl interactions into layers,and these layers exhibit two different orientations,displaying a rare 2D to 3D interpenetration mode.The zigzag chains in 2 are parallelly arranged.{[Zn_(3)(DPA)_(3)Br_(6)]·2DMF·_(1.5)H_(2)O}n(3)is isostructural to 2.3 was obtained using ZnBr_(2)instead of ZnCl_(2).[M(DPA)(formate)_(2)(H_(2)O)_(2)]n[M=Co(4),Cu(5)]are isostructural,contain chain structures formed by DPA,Cu^(2+)/Co^(2+),and for-mate ions,which were formed in situ in the solvothermal reaction.{[Zn(DIP)_(2)Cl]ClO_(4)}n(6)contains a layer structure formed by DIP and Zn^(2+).Free DPA and DIP ligands exhibited high fluorescence at room temperature,and coordina-tion polymers 3 and 6 displayed enhanced fluorescent emissions.展开更多
We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),campho...We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5.展开更多
Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the dev...Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the development of prostate cancer.However,as one of the main carcinogens in cigarette smoke,the role of benzo[a]pyrene(BaP)in prostate cancer is still unclear.The current study aimed to investgate the impacts of BaP exposure on the progression of PCa towardmalignancy and the regulation of the immune microenvironment.We verified that BaP exposure can promote the proliferation,migration,and apoptosis of prostate cancer cells through in vitro experiments.We constructed a subcutaneous xenograft tumor model of BaP exposure mouse and found that can promote the proliferation of tumors in vivo.Organoids-driven by PCa patients showed higher growth rate under BaP exposure.Flow cytometric analysis demonstrated a remarkable decrease in CD4^(+)T and CD8^(+)T cell infiltration levels.Moreover,we identified four genes(Mdm2,Ar,Foxo1,Crebbp)were strongly associated with BaP exposure by combining mouse tumor RNA-seq and CTD database.Additionally,a nomogram integrating clinicopathological features was constructed to assess the prognosis of prostate cancer patients under BaP exposure.This study systematically proved that BaP exposure promotes malignant progression of PCa and suppresses the immune microenvironment,in which Mdm2,Ar,Foxo1,Crebbp may play a crucial role in inhibiting apoptosis.These findings offer novel insights into themechanisms via which BaP exposure contributes to PCa development.展开更多
Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and ...Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and feeding behavior of the seahorse,Hippocampus erectus were studied.The growth parameters,pollutant bioaccumulation,enzymatic response,and feeding dynamics were extensively analyzed.Seahorses exposed to microplastics-borne B[a]P and heavy metals exhibited notable reductions in body length and weight,as well as in survival rates,indicating severe stress from these contaminants.The accumulation of pollutant particularly B[a]P in seahorse exceeded China’s national regulatory limit of 5μg/kg,and the B[a]P accumulation in seahorses was obviously aided by HDPE microplastics,posing a risk to marine organisms and human health via the food chain.The adaptive response of the seahorses was evident shown in the elevation of antioxidant enzyme activities,which is a biological mechanism to mitigate oxidative stress induced by the pollutants.However,this physiological adaptation comes at a cost,as evidenced by marked changes in the feeding behavior.Results show that the efficiency and frequency of feeding were greatly reduced,indicating a heavy impact on the ecological role and survival of this marine creature in polluted habitats.This research offers a crucial perspective on the compound threats of microplastics and associated pollutants in marine ecosystems.It highlights the urgent need develop comprehensive strategies to address these environmental issues.The findings are an important contribution to ecotoxicology,providing a deeper understanding of how microplastics act as vectors for other contaminants and their profound effects on marine life,especially species like seahorses.This study calls for action to strengthen environmental policies and practices aimed at mitigating the impact of marine pollution.展开更多
High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,howe...High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,however,possess the ability to overcome these challenges,primarily through various enzymes with broad substrate specificity,including cytochrome P450(CYP450),laccase,manganese peroxidase,lignin peroxidase.As a result,the development of efficient fungal strains capable of degrading HMW-PAHs is essential for advancing bioremediation strategies.In this study,Aspergillus fumigatus Z5 was isolated from a contaminated site and demonstrated a remarkable ability to degrade the highly recalcitrant benzo[a]pyrene,achieving a degradation rate of 75.43%.Transcriptomic analysis revealed significant upregulation of 34 CYP450 genes.Among these genes,CYP3A4(gene 8840)showed strong binding affinity for benzo[a]pyrene,as confirmed by molecular docking studies,indicating its key role in the biodegradable process.Furthermore,the metabolic network analysis showed that the electron transfer required for CYP450-mediated oxidative reactions enhanced mitochondrial oxidative phosphorylation and subsequently energy metabolism in A.fumigatus Z5.This metabolic coordination likely facilitates the complete degradation of benzo[a]pyrene.Our study illuminates the fundamental roles of CYP450 from A.fumigatus Z5 in benzo[a]pyrene degradation and provides novel insight into designing and implementing enhanced bioremediation strategies.展开更多
[Objective]The paper was to explore the effects of pyrene stress on growth and physiological indexes of maize seedling.[Method] The effects of different concentrations of pyrene（0,0.5,1.0,and 2.0 mg/L） on growth and...[Objective]The paper was to explore the effects of pyrene stress on growth and physiological indexes of maize seedling.[Method] The effects of different concentrations of pyrene（0,0.5,1.0,and 2.0 mg/L） on growth and several physiological indexes,such as chlorophyll content,malnodiadehyde（MDA） content of both leaves and roots of maize（Zea Mays L.） seedlings of Shixiang 1（sensitive variety） and Guangtian 3（tolerant variety） were studied by a hydroponic experiment.[Result]As the concentration of prene increasing within the test concentration range,the contents of chlorophyll a and chlorophyll b in Shixiang 1 first increased and then decreased;relative growth yield and absolute growth rate showed the decreasing trend;MDA contents in roots and leaves showed the increasing trend.Relative growth yield,absolute growth rate and chlorophyll a content in Guangtian 3 first increased and then decreased;chlorophyll b and MDA contents in roots showed the increasing trend;MDA contents in leaves showed the decreasing trend.Compared with control,chlorophyll a and chlorophyll b contents of Shixiang 1 significantly increased under pyrene concentration of 0.5-1.0 mg/L,which significantly decreased as the concentration of pyrene ≥2.0 mg/L;MDA contents in roots and leaves significantly increased as the concentration of pyrene ≥1.0 mg/L,while relative growth yield and absolute growth rate significantly decreased.Chlorophyll a and chlorophyll b contents in Guangtian 3 significantly increased as the concentration of pyrene ≥1.0 mg/L.Pyrene concentration had significantly negative correlation with relative growth yield and absolute growth rate of Shixiang 1,while it had significant positive correlation with MDA contents in roots.Pyrene concentration had significant positive correlation with chlorophyll b and MDA contents in roots of tolerant variety Guangtian 3.[Conclusion]The study provided basis for the management measures of maize during its seedling stage.展开更多
A preliminary study on application of Pluorometric Analysis ofDNA Unwinding（FADU）to the detection of DNA strand breaksinduced by indirect environmental mutagen benzo（a）pyrene（BaP）was conducted.The results showed...A preliminary study on application of Pluorometric Analysis ofDNA Unwinding（FADU）to the detection of DNA strand breaksinduced by indirect environmental mutagen benzo（a）pyrene（BaP）was conducted.The results showed that BaP,activated by PCB-in-duced rat liver S<sub>9</sub>mixture,could result in obvious increase of DNAstrand breaks in human peripheral leukocytes incubated with展开更多
The peroxynitrite/porphyrin biomimetic system was established to investigate the effects of peroxynitrite on benzo[a]pyrene （B[a]P） metabolism. Three model systems consisting of different iron porphyrins were compar...The peroxynitrite/porphyrin biomimetic system was established to investigate the effects of peroxynitrite on benzo[a]pyrene （B[a]P） metabolism. Three model systems consisting of different iron porphyrins were compared, and the results showed that the peroxynitdte/T（p-Cl）PPFeCl system was the highest catalytic efficiency in the metabolism of B [a]P. We analyzed the B [a]P metabolites produced from this system by RP-HPLC method and firstly identified the formation of nitrobenzo[a]pyrenes which are the special metabolites of B [a]P induced by peroxynitrite.展开更多
Understanding relationships between molecular structures and fluorescent properties is critical to enable rational deployment of fluorophores. 1-Acetyl pyrene is an important pyrene-derivative, used extensively as an ...Understanding relationships between molecular structures and fluorescent properties is critical to enable rational deployment of fluorophores. 1-Acetyl pyrene is an important pyrene-derivative, used extensively as an environment-sensitive probe. In the past, the fluorescence of 1-acetylpyrene was considered to be polarity-sensitive with a large positive solvatochromism, and its monomer emissions were believed in the range of 410-470 nm. In this paper, our experimental and theoretical studies showed that the monomer fluorescence of 1-acetylpyrene is centered at ～390 nm,which is similar to that of pyrene dyes and not polarity-sensitive. Previously observed "monomer emission" has been re-assigned to that of dimers, which represent the dominant existence form of 1-acetylpyrene in the solution phase,as a result of strong intermolecular π-π stacking interactions.展开更多
With high performance liquid chromatograph and fluorospectrometry, 1-hydroxypyrene is identified as a metabolite of pyrene in the urine of dogs after intramuscular injection of pyrene. When three successive doses of 1...With high performance liquid chromatograph and fluorospectrometry, 1-hydroxypyrene is identified as a metabolite of pyrene in the urine of dogs after intramuscular injection of pyrene. When three successive doses of 1,2 and 5 μmol/kg wt. pyrene administered, urinary excretion of 1-hydroxypyrene reaches the peak level between 24th and 48th hours. Excreted 1-hydroxypyrene consists of only about 0.05% of injected pyrene.展开更多
The structure, electronic properties, and chemical reactivity of pyrene and its three monochlorinated derivatives have been theoretically studied by using density functional theory (DFT). Several methods and basis set...The structure, electronic properties, and chemical reactivity of pyrene and its three monochlorinated derivatives have been theoretically studied by using density functional theory (DFT). Several methods and basis sets are tested for the optimization of the geometrical structure and the B3LYP/6-311G** method/basis set is found to be the most suitable in predicting the heat of formation of pyrene and the minimum energy optimized structure of pyrene and its monochlorinated derivatives. The geometrical parameters and the heat of formation of pyrene are in good agreement with available experimental data. The chemical reactivity and stability of the four compounds are investigated. The computed results agree well with experimental results of monochlorination of the pyrene molecule. The relative stability of the monochlorinated pyrene compounds is in the order: 1-chloropyrene > 4-chloropyrene > 2-chloropyrene.展开更多
AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-induce...AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-inducedforestomach tumor was established according tothe methods of Wattenberg with slightmodifications. One hundred and eighty femalemice (6 weeks old) were divided into six groupsequally; negative control (Succinic acid),vehicle control ( Succinate + B (a) P), positivecontrol(B(a) P), high VES(2.5g/kg. b. w + B(a)P), Iow VES(1 .25 g/kg. b. w + B(a) P) ig as wellas VES by ip (20 mg/kg, b. w + B(a) P). Exceptthe negative control group, the mice wereadministrated with B(a)P ig. and correspondingtreatments for 4 weeks to study the anti-carcinogenetic effect of VES during the initiationperiod. The experiment lasted 29 weeks, inwhich the inhibitory effects of VES both ontumor incidence and tumor size were tested.RESULTS The models of B (a)P-inducedforestomach tumor in female mice wereestablished successfully. Some werecauliflower-like, others looked like papilla, evena few were formed into the ulcer cavities. VES at1.25 g/kg. b. w, 2.5 g/kg. b.w. by ig and 20 mg/kg. b. w. via ip could decrease the number oftumors per mouse (1.7 ± 0. 41, 1.6 ± 0.34 and 1.1±0.43), being lower than that of B(a)P group(5.4 ± 0.32, P＜0.05). The tumor incidence wasinhibited by 18.2%, 23.1% and 50.0%. VES at1.25g/kg.b.w., 2.5 g/ kg.b.w. by ig and20 mg/kg. b.w. via ip reduced the total volumeof tumors per mouse (54.8 ± 8.84, 28.4 ± 8.32and 23.9± 16.05), being significantly lower thanthat of B(a)P group (150.2±20.93, P＜0.01).The inhibitory rates were 63.5%, 81.1% and84.1%, respectively.CONCLUSION VES has inhibitory effects on B(a) P-induced forestomach carcinogenesis infemale mice, especially by ip and it may be apotential anti-cancer agent in vivo.展开更多
Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons （PAHs） were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a...Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons （PAHs） were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene （BaP）. The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope （SEM） analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.展开更多
Phytoremediation of soil contaminated with phenanthrene and pyrene was investigated using twelve plant species. Plant uptake and accumulation of these chemicals were evaluated. At the end of the experiment(45 d), the ...Phytoremediation of soil contaminated with phenanthrene and pyrene was investigated using twelve plant species. Plant uptake and accumulation of these chemicals were evaluated. At the end of the experiment(45 d), the remaining respective concentrations of soil phenanthrene and pyrene in spiked vegetated soils, with initial phenanthrene of 133 3 mg/kg and pyrene of 171 5 mg/kg, were 8 71—16 4 and 44 9—65 0 mg/kg, generally 4 7%—49 4% and 7 1%—35 9% lower than their concentrations in the non vegetated soils. The loss of phenanthrene and pyrene in vegetated spiked soils were 88 2%—93 0% and 62 3%—73 8% of the added amounts of these contaminants, respectively. Although plant uptake and accumulation of these compounds were evident, and root concentrations and RCFs(root concentration factors; defined as the ratio of PAH concentrations in roots and in the soils on a dry weight basis) of these compounds significantly positively correlated to root lipid contents, plant uptake and accumulation only accounted for less than 0 01% and 0 23% of the enhanced loss of these chemicals in vegetated versus non vegetated soils. In contrast, plant promoted microbial biodegradation was the dominant mechanism of the phytoremediation for soil phenanthrene and pyrene contamination. Results from this study suggested a feasibility of the establishment of phytoremediation for soil PAH contamination.展开更多
It has been reported that there is an interaction between Benzo[a]pyrene （BaP）, a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin （TBT）, an organometal used as an antifouling biocide. This...It has been reported that there is an interaction between Benzo[a]pyrene （BaP）, a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin （TBT）, an organometal used as an antifouling biocide. This study was therefore designed to examine the potential in vivo influence of BaP, TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus. The fish were exposed to water containing environmentally relevant concentrations of BaP, TBT and their mixture. Spleens were collected for biochemical analysis after exposure for 7, 25, 50 d and after recovery for 7, 20 d. Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione peroxidase （GPx） activity by BaP or TBT alone. The cotreatment for 25 and 50 d resulted in inhibition of GPx activity, which was similar to the effect of TBT. Splenic glutathione S-transferase （GST） activities were significantly elevated in S. marmoratus exposed to BaP starting from 7 d and remained high up to 25 d. However, no further activity change was found with prolonged exposure. Cotreatment of BaP and TBT primarily inhibited the GST activity, which was similar to the effect of TBT. Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH （glutathione） by BaP or TBT alone. MDA （malondialdehyde） contents in spleen of S. marmoratus were not significantly altered compared with the control during the test period. Spleen, as an immune organ, is sensitive to exposure of BaP or TBT. It should have an effective mechanism to counteract oxidative damage. Antioxidative defense systems in spleen of S. marmoratus should be considered as potential biomarkers. Short-term exposure of BaP or TBT could result in induction of antioxidant defense system. A significant decrease of these indices, such as GSH, GST, GPx might indicate more severe contamination.展开更多
The rates of photodegradation and photocatalysis of benzo [a]pyrene （BaP） on soil surfaces under UV light have been studied. Different parameters such as temperature, soil particle sizes, and soil depth responsible ...The rates of photodegradation and photocatalysis of benzo [a]pyrene （BaP） on soil surfaces under UV light have been studied. Different parameters such as temperature, soil particle sizes, and soil depth responsible for photodegradation, catalyst loads and wavelength of UV irradiation blamed for photocatalysis have been monitored. The results obtained indicated that BaP photodegradation follows pseudo-first-order kinetics. BaP photodegradation was the fastest at 30℃ . The rates of BaP photodegradation at different soil particle size followed the order： less than 1 mm〉less than 0.45 mm〉less than 0.25 mm. When the soil depth increased from 1 mm to 4 ram, the half-life increased from 13.23 d to 17.73 d. The additions of TiO2 or Fe2O3 accelerated the photodegradation of BaP, and the photocatalysis of BaP follows pseudo-first-order kinetics. Changes in catalyst loads of TiO2 （0.5%, 1%, 2%, and 3% （wt）） or Fe203 （2%, 5%, 7%, and 10% （wt）） did not significantly affect the degradation rates. Both BaP photocatalysis in the presence of TiO2 and Fe2O3 were the fastest at 254 nm UV irradiation.展开更多
Seedling emergence tests were conducted in a meadow brown soil using five plant species(i.e., Chinese cabbage, green onion, tomato, turnip and wheat) to determine the phytotoxicity of phenanthrene, pyrene and their mi...Seedling emergence tests were conducted in a meadow brown soil using five plant species(i.e., Chinese cabbage, green onion, tomato, turnip and wheat) to determine the phytotoxicity of phenanthrene, pyrene and their mixtures. The soil was amended with up to 1000 mg/kg soil of phenanthrene or 600 mg/kg soil of pyrene. Seedling emergence and root growth were measured. The results indicated that root elongation was more sensitive than seedling emergence. Root length decreased with increasing phenanthrene or pyrene concentrations(p≤0 05). Phenanthrene was more phytotoxic than pyrene. The lowest observable adverse effect concentration(LOAEC) was 10 mg/kg for phenanthrene when tested with green onion, and 50 mg/kg for pyrene when tested with wheat. Among the five species, wheat was found to be the most sensitive. When amended jointly at or below their respective LOAEC, phenanthrene and pyrene produced a synergistic toxic effect.展开更多
基金This study was supported by National Key Basic Research and Development Program of China (No.2002CB512905)National Natural Science Foundation of China (No.30371204).
文摘Objective To investigate the application of BPDE-albumin adducts as monitoring biomarkers for coke oven workers exposed to polycyclic aromatic hydrocarbons （PAHs） and to explore possible relationship between BPDE-albumin adducts and urinary 1-hydroxypyrene （1-OHP） levels in them. Methods Thirty-seven coke oven workers from a coke plant and 47 controls without the occupational exposure to PAHs were recruited in this study. The levels of plasma BPDE-albumin adducts and urinary 1-OHP were analyzed using high performance liquid chromatography. Results The median levels of BPDE-albumin adducts （42.10 fmol/mg albumin） and urinary 1-OHP （5.46 μmol/mol creatinine） were significantly higher in coke oven workers than in controls （14.16 fmol/mg albumin, 2.96μmol/mol creatinine, respectively; P〈0.01）. Multiple logistic regression analysis showed that coke oven workers were at higher risk of having BPDE-albumin adduct levels above 25.30 μmol/mg albumin （OR=1.79, P〈0.01） and urinary 1-OHP levels above 4.13 μmol/mol creatinine （OR=2.45, P〈0.05）. There was a positive correlation between the levels of BPDE-albumin adducts and urinary 1-OHP in all subjects （rs=0.349, P〈0.01）. Conclusion BPDE-albumin adduct is a useful biomarker for monitoring long-term exposure to PAHs, and plasma BPDE-albumin adducts level is significantly correlated to urinary 1-OHP levels in coke oven workers.
基金supported by the National Key R&D Program of China(No.2020YFC1808803).
文摘Benzo[a]pyrene(B[a]P)is a carcinogenic environmental pollutant widely present in the environment and can enter the human body through the food chain.It is therefore essential to treat and remediate the B[a]P-contaminated environment.Microbial remediation of B[a]Pcontaminated environments is considered to be one of the most effective strategies,and the addition of biostimulants is a feasible method to further improve the effectiveness of microbial remediation.In this study,we used Bacillus subtilis MSC4 to screen for the stimulation of sodium gluconate,which promoted B[a]P degradation.Based on biochemical and transcriptomic analyses,Sodium gluconate was found to significantly increase the biomass of MSC4 and the expression of most genes involved in B[a]P degradation.Activities of central carbon metabolism,fatty acidβ-oxidation and oxidative phosphorylation were all promoted.The significant increase in acid-induced oxalate decarboxylase expression indicates a decrease in intracellular pH,which promoted the synthesis of acetoin and lactate.Genes involved in the nitrogen cycle,especially nitrification and denitrification,were significantly up-regulated,contributing to B[a]P degradation.Genes involved in the synthesis of enzyme cofactors,including thiamine,molybdenum cofactors,NAD and heme,were up-regulated,which contributes to increasing enzyme activity in metabolic pathways.Up-regulation of genes in flagella assembly,chemotaxis,and lipopeptide synthesis is beneficial for the dissolution and uptake of B[a]P.Genes related to the sugar transport system were upregulated,which facilitates the transport and absorption of monosaccharides and oligosaccharides by MSC4.This study provides a theoretical basis for the further application of sodium gluconate in the treatment of PAH-contaminated sites.
文摘Six coordination polymers based on 9,10-di(pyridine-4-yl)-anthracene(DPA)and 1,6-di(1H-imidazol-1-yl)pyrene(DIP)were obtained by solvothermal reactions.{[Zn(DPA)Cl_(2)]·DMF·2H_(2)O}n(1)and{[Zn_(1.5)(DPA)_(1.5)Cl_(3)]·5H_(2)O}n(2)are framework isomers,which both contain zigzag chains formed by DPA,Zn^(2+),and Cl-.The zigzag chains in 1 are further assembled by C—H…Cl interactions into layers,and these layers exhibit two different orientations,displaying a rare 2D to 3D interpenetration mode.The zigzag chains in 2 are parallelly arranged.{[Zn_(3)(DPA)_(3)Br_(6)]·2DMF·_(1.5)H_(2)O}n(3)is isostructural to 2.3 was obtained using ZnBr_(2)instead of ZnCl_(2).[M(DPA)(formate)_(2)(H_(2)O)_(2)]n[M=Co(4),Cu(5)]are isostructural,contain chain structures formed by DPA,Cu^(2+)/Co^(2+),and for-mate ions,which were formed in situ in the solvothermal reaction.{[Zn(DIP)_(2)Cl]ClO_(4)}n(6)contains a layer structure formed by DIP and Zn^(2+).Free DPA and DIP ligands exhibited high fluorescence at room temperature,and coordina-tion polymers 3 and 6 displayed enhanced fluorescent emissions.
文摘We report five coordination polymers(CPs)based on fluorescent ligands[1,6-di(1H-imidazol-1-yl)pyrene(dip),9,10-di(1H-imidazol-1-yl)anthracene(dia)]and anionic ligands[cyclohexane-1,4-dicarboxylic acid(H_(2)cda),camphoric acid(H_(2)cpa)].In[Cd(dip)(cda)]·4H_(2)O}_(n)(1),the Cd^(2+)ions,acting as tetrahedral nodes,are linked by dipand cda^(2-)ligands with four Cd^(2+)ions into five-fold interpenetrating network array of topology of dia.In{[Cd(dip)(cpa)]·4H_(2)O}_(n)(2),the Cd^(2+)ions,acting as a 4-connector,are linked by cpa^(2-)and dip ligands into a 3D framework ofcds topology.In{[Ni(dia)_(2)Cl_(2)]·DMF}_(n)(3),the Ni^(2+)ion is linked by four dia ligands into a layer structure,and 1Dchannels of a cross-section of 1.35 nm×0.96 nm are formed.In{[Cd(dia)_(2)(H_(2)O)_(2)](NO_(3))_(2)·2DMSO}n(4),the dia ligandsconnected Cd^(2+)ions into a 2D layer,and 1D channels are formed between adjacent layers with a cross-section of0.87 nm×0.43 nm.In[Zn(dip)Cl_(2)]_(n)(5),the Zn^(2+)ion is linked by dip ligands into an infinite 1D chain.The infrared,thermal gravimetric,and fluorescent emission data were collected and analyzed for these coordination polymers.CCDC:2356055,1;2440075,2;2356057,3;2356057,4;2356059,5.
基金supported by the National Key Research and Development Program of China(No.2022YFB3804504)the National Natural Science Foundation of China,Youth Project(Nos.82101838,82203367,82203505,and 82203403)the Experimental Animal Fund of Shanghai Science and Technology Commission(No.22140903800).
文摘Epidemiological studies indicate that prostate cancer(PCa)is the second prevalent malignant tumor affecting men globally.Environmental pollution such as cigarette smoke is one of the important risk factors for the development of prostate cancer.However,as one of the main carcinogens in cigarette smoke,the role of benzo[a]pyrene(BaP)in prostate cancer is still unclear.The current study aimed to investgate the impacts of BaP exposure on the progression of PCa towardmalignancy and the regulation of the immune microenvironment.We verified that BaP exposure can promote the proliferation,migration,and apoptosis of prostate cancer cells through in vitro experiments.We constructed a subcutaneous xenograft tumor model of BaP exposure mouse and found that can promote the proliferation of tumors in vivo.Organoids-driven by PCa patients showed higher growth rate under BaP exposure.Flow cytometric analysis demonstrated a remarkable decrease in CD4^(+)T and CD8^(+)T cell infiltration levels.Moreover,we identified four genes(Mdm2,Ar,Foxo1,Crebbp)were strongly associated with BaP exposure by combining mouse tumor RNA-seq and CTD database.Additionally,a nomogram integrating clinicopathological features was constructed to assess the prognosis of prostate cancer patients under BaP exposure.This study systematically proved that BaP exposure promotes malignant progression of PCa and suppresses the immune microenvironment,in which Mdm2,Ar,Foxo1,Crebbp may play a crucial role in inhibiting apoptosis.These findings offer novel insights into themechanisms via which BaP exposure contributes to PCa development.
基金Supported by the Marine Economic Development Project(No.GDNRC[2022]36)the National Key Research and Development Program of China(No.2018YFD0900206)the Tianjin Science and Technology Program Project(No.21YDTPJC00340)。
文摘Marine pollution poses a critical threat to biodiversity.The synergistic effects of microplastics,specifically high-density polyethylene(HDPE),combined with benzo[a]pyrene(B[a]P)and heavy metals,on the physiology and feeding behavior of the seahorse,Hippocampus erectus were studied.The growth parameters,pollutant bioaccumulation,enzymatic response,and feeding dynamics were extensively analyzed.Seahorses exposed to microplastics-borne B[a]P and heavy metals exhibited notable reductions in body length and weight,as well as in survival rates,indicating severe stress from these contaminants.The accumulation of pollutant particularly B[a]P in seahorse exceeded China’s national regulatory limit of 5μg/kg,and the B[a]P accumulation in seahorses was obviously aided by HDPE microplastics,posing a risk to marine organisms and human health via the food chain.The adaptive response of the seahorses was evident shown in the elevation of antioxidant enzyme activities,which is a biological mechanism to mitigate oxidative stress induced by the pollutants.However,this physiological adaptation comes at a cost,as evidenced by marked changes in the feeding behavior.Results show that the efficiency and frequency of feeding were greatly reduced,indicating a heavy impact on the ecological role and survival of this marine creature in polluted habitats.This research offers a crucial perspective on the compound threats of microplastics and associated pollutants in marine ecosystems.It highlights the urgent need develop comprehensive strategies to address these environmental issues.The findings are an important contribution to ecotoxicology,providing a deeper understanding of how microplastics act as vectors for other contaminants and their profound effects on marine life,especially species like seahorses.This study calls for action to strengthen environmental policies and practices aimed at mitigating the impact of marine pollution.
基金supported by the National Key R&D Program of China(No.2021YFC1808902)the National Natural Science Foundation of China(No.31770152)+1 种基金Shaanxi Fundamental Science Research Project for Chemistry&Biology(No.22JHZ008)the Natural Science Foundation of Gansu Province of China(No.23JRRM738).
文摘High molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs)pose significant environmental challenges due to their complex structures and persistent toxicity,and are difficult to be degraded by bacteria.Fungi,however,possess the ability to overcome these challenges,primarily through various enzymes with broad substrate specificity,including cytochrome P450(CYP450),laccase,manganese peroxidase,lignin peroxidase.As a result,the development of efficient fungal strains capable of degrading HMW-PAHs is essential for advancing bioremediation strategies.In this study,Aspergillus fumigatus Z5 was isolated from a contaminated site and demonstrated a remarkable ability to degrade the highly recalcitrant benzo[a]pyrene,achieving a degradation rate of 75.43%.Transcriptomic analysis revealed significant upregulation of 34 CYP450 genes.Among these genes,CYP3A4(gene 8840)showed strong binding affinity for benzo[a]pyrene,as confirmed by molecular docking studies,indicating its key role in the biodegradable process.Furthermore,the metabolic network analysis showed that the electron transfer required for CYP450-mediated oxidative reactions enhanced mitochondrial oxidative phosphorylation and subsequently energy metabolism in A.fumigatus Z5.This metabolic coordination likely facilitates the complete degradation of benzo[a]pyrene.Our study illuminates the fundamental roles of CYP450 from A.fumigatus Z5 in benzo[a]pyrene degradation and provides novel insight into designing and implementing enhanced bioremediation strategies.
基金The project supported by the State Key Develoment Program for Basic Research of China(2003CB716204)the Key Project of the Education Department of China(2005360563)+1 种基金the Key Laboratory of Advanced Photonic and Electronic Materials of Jiangsuthe State Key Laboratory of Solid State Microstructures in Nanjing University.
基金Supported Natural Science Foundation of Guangdong Province(9451064201003780)President Fund in South China Agricultural University(K09219)Students Technology Innovation Project in South China Agricultural University(L09131)~~
文摘[Objective]The paper was to explore the effects of pyrene stress on growth and physiological indexes of maize seedling.[Method] The effects of different concentrations of pyrene（0,0.5,1.0,and 2.0 mg/L） on growth and several physiological indexes,such as chlorophyll content,malnodiadehyde（MDA） content of both leaves and roots of maize（Zea Mays L.） seedlings of Shixiang 1（sensitive variety） and Guangtian 3（tolerant variety） were studied by a hydroponic experiment.[Result]As the concentration of prene increasing within the test concentration range,the contents of chlorophyll a and chlorophyll b in Shixiang 1 first increased and then decreased;relative growth yield and absolute growth rate showed the decreasing trend;MDA contents in roots and leaves showed the increasing trend.Relative growth yield,absolute growth rate and chlorophyll a content in Guangtian 3 first increased and then decreased;chlorophyll b and MDA contents in roots showed the increasing trend;MDA contents in leaves showed the decreasing trend.Compared with control,chlorophyll a and chlorophyll b contents of Shixiang 1 significantly increased under pyrene concentration of 0.5-1.0 mg/L,which significantly decreased as the concentration of pyrene ≥2.0 mg/L;MDA contents in roots and leaves significantly increased as the concentration of pyrene ≥1.0 mg/L,while relative growth yield and absolute growth rate significantly decreased.Chlorophyll a and chlorophyll b contents in Guangtian 3 significantly increased as the concentration of pyrene ≥1.0 mg/L.Pyrene concentration had significantly negative correlation with relative growth yield and absolute growth rate of Shixiang 1,while it had significant positive correlation with MDA contents in roots.Pyrene concentration had significant positive correlation with chlorophyll b and MDA contents in roots of tolerant variety Guangtian 3.[Conclusion]The study provided basis for the management measures of maize during its seedling stage.
文摘A preliminary study on application of Pluorometric Analysis ofDNA Unwinding（FADU）to the detection of DNA strand breaksinduced by indirect environmental mutagen benzo（a）pyrene（BaP）was conducted.The results showed that BaP,activated by PCB-in-duced rat liver S<sub>9</sub>mixture,could result in obvious increase of DNAstrand breaks in human peripheral leukocytes incubated with
基金Project supported by the Beijing Natural Science Foundation (No. 2052004)the Beijing Nova Programme (No. 2003B05) the National Natural Science Foundation of China (No. 20605002).
文摘The peroxynitrite/porphyrin biomimetic system was established to investigate the effects of peroxynitrite on benzo[a]pyrene （B[a]P） metabolism. Three model systems consisting of different iron porphyrins were compared, and the results showed that the peroxynitdte/T（p-Cl）PPFeCl system was the highest catalytic efficiency in the metabolism of B [a]P. We analyzed the B [a]P metabolites produced from this system by RP-HPLC method and firstly identified the formation of nitrobenzo[a]pyrenes which are the special metabolites of B [a]P induced by peroxynitrite.
基金financially supported by the National Natural Science Foundation of China(Nos. 21878286, 21502189)DICP (Nos. DMT0201603, TMSR201601)+1 种基金the financial support from Singapore University of Technology and Design (SUTD)the SUTD-MIT International Design Centre (Nos. T1SRCI17126, IDD21700101, IDG31800104)
文摘Understanding relationships between molecular structures and fluorescent properties is critical to enable rational deployment of fluorophores. 1-Acetyl pyrene is an important pyrene-derivative, used extensively as an environment-sensitive probe. In the past, the fluorescence of 1-acetylpyrene was considered to be polarity-sensitive with a large positive solvatochromism, and its monomer emissions were believed in the range of 410-470 nm. In this paper, our experimental and theoretical studies showed that the monomer fluorescence of 1-acetylpyrene is centered at ～390 nm,which is similar to that of pyrene dyes and not polarity-sensitive. Previously observed "monomer emission" has been re-assigned to that of dimers, which represent the dominant existence form of 1-acetylpyrene in the solution phase,as a result of strong intermolecular π-π stacking interactions.
基金This project is funded by the National Natural Sciences Foundation of China, and partially supported by Beijing Municiple Environmental Protection Bureau.
文摘With high performance liquid chromatograph and fluorospectrometry, 1-hydroxypyrene is identified as a metabolite of pyrene in the urine of dogs after intramuscular injection of pyrene. When three successive doses of 1,2 and 5 μmol/kg wt. pyrene administered, urinary excretion of 1-hydroxypyrene reaches the peak level between 24th and 48th hours. Excreted 1-hydroxypyrene consists of only about 0.05% of injected pyrene.
文摘The structure, electronic properties, and chemical reactivity of pyrene and its three monochlorinated derivatives have been theoretically studied by using density functional theory (DFT). Several methods and basis sets are tested for the optimization of the geometrical structure and the B3LYP/6-311G** method/basis set is found to be the most suitable in predicting the heat of formation of pyrene and the minimum energy optimized structure of pyrene and its monochlorinated derivatives. The geometrical parameters and the heat of formation of pyrene are in good agreement with available experimental data. The chemical reactivity and stability of the four compounds are investigated. The computed results agree well with experimental results of monochlorination of the pyrene molecule. The relative stability of the monochlorinated pyrene compounds is in the order: 1-chloropyrene > 4-chloropyrene > 2-chloropyrene.
基金Project Supported by National Natural Science Foundation of China, No. 39870662
文摘AIM To study the inhibitory effects of VES( RRR-α-tocopheryl Succinate, VES ), aderivative of natural Vitamin E, on benzo (a)pyrene (B (a) P)-induced forestomach tumor infemale mice.METHODS The model of B (a)P-inducedforestomach tumor was established according tothe methods of Wattenberg with slightmodifications. One hundred and eighty femalemice (6 weeks old) were divided into six groupsequally; negative control (Succinic acid),vehicle control ( Succinate + B (a) P), positivecontrol(B(a) P), high VES(2.5g/kg. b. w + B(a)P), Iow VES(1 .25 g/kg. b. w + B(a) P) ig as wellas VES by ip (20 mg/kg, b. w + B(a) P). Exceptthe negative control group, the mice wereadministrated with B(a)P ig. and correspondingtreatments for 4 weeks to study the anti-carcinogenetic effect of VES during the initiationperiod. The experiment lasted 29 weeks, inwhich the inhibitory effects of VES both ontumor incidence and tumor size were tested.RESULTS The models of B (a)P-inducedforestomach tumor in female mice wereestablished successfully. Some werecauliflower-like, others looked like papilla, evena few were formed into the ulcer cavities. VES at1.25 g/kg. b. w, 2.5 g/kg. b.w. by ig and 20 mg/kg. b. w. via ip could decrease the number oftumors per mouse (1.7 ± 0. 41, 1.6 ± 0.34 and 1.1±0.43), being lower than that of B(a)P group(5.4 ± 0.32, P＜0.05). The tumor incidence wasinhibited by 18.2%, 23.1% and 50.0%. VES at1.25g/kg.b.w., 2.5 g/ kg.b.w. by ig and20 mg/kg. b.w. via ip reduced the total volumeof tumors per mouse (54.8 ± 8.84, 28.4 ± 8.32and 23.9± 16.05), being significantly lower thanthat of B(a)P group (150.2±20.93, P＜0.01).The inhibitory rates were 63.5%, 81.1% and84.1%, respectively.CONCLUSION VES has inhibitory effects on B(a) P-induced forestomach carcinogenesis infemale mice, especially by ip and it may be apotential anti-cancer agent in vivo.
基金The National Basic Research Program (973) of China (No. 2004CB418506)the National Natural Science Foundation of China (No.20337010) the Hi-Tech Research and Development Program (863) of China (No. 2004AA649060)
文摘Two indigenous microorganisms, Bacillus sp. SB02 and Mucor sp. SF06, capable of degrading polycyclic aromatic hydrocarbons （PAHs） were co-immobilized on vermiculite by physical adsorption and used to degrade benzo[a] pyrene （BaP）. The characteristics of BaP degradation by both free and co-immobilized microorganism were then investigated and compared. The removal rate using the immobilized bacterial-fungal mixed consortium was higher than that of the freely mobile mixed consortium. 95.3% of BaP was degraded using the co-immobilized system within 42 d, which was remarkably higher than the removal rate of that by the free strains. The optimal amount of inoculated co-immobilized system for BaP degradation was 2%. The immobilized bacterial-fungal mixed consortium also showed better water stability than the free strains. Kinetics of BaP biodegradation by co-immobilized SF06 and SB02 were also studied. The results demonstrated that BaP degradation could be well described by a zero-order reaction rate equation when the initial BaP concentration was in the range of 10--200 mg/kg. The scanning electronic microscope （SEM） analysis showed that the co-immobilized microstructure was suitable for the growth of SF06 and SB02. The mass transmission process of co-immobilized system in soil is discussed. The results demonstrate the potential for employing the bacterial-fungal mixed consortium, co-immobilized on vermiculite, for in situ bioremediation of BaP.
文摘Phytoremediation of soil contaminated with phenanthrene and pyrene was investigated using twelve plant species. Plant uptake and accumulation of these chemicals were evaluated. At the end of the experiment(45 d), the remaining respective concentrations of soil phenanthrene and pyrene in spiked vegetated soils, with initial phenanthrene of 133 3 mg/kg and pyrene of 171 5 mg/kg, were 8 71—16 4 and 44 9—65 0 mg/kg, generally 4 7%—49 4% and 7 1%—35 9% lower than their concentrations in the non vegetated soils. The loss of phenanthrene and pyrene in vegetated spiked soils were 88 2%—93 0% and 62 3%—73 8% of the added amounts of these contaminants, respectively. Although plant uptake and accumulation of these compounds were evident, and root concentrations and RCFs(root concentration factors; defined as the ratio of PAH concentrations in roots and in the soils on a dry weight basis) of these compounds significantly positively correlated to root lipid contents, plant uptake and accumulation only accounted for less than 0 01% and 0 23% of the enhanced loss of these chemicals in vegetated versus non vegetated soils. In contrast, plant promoted microbial biodegradation was the dominant mechanism of the phytoremediation for soil phenanthrene and pyrene contamination. Results from this study suggested a feasibility of the establishment of phytoremediation for soil PAH contamination.
基金Project supported by the National Natural Science Foundation of China(No.20447001, 40476049)the Natural Science Foundation of Fujian Province of China(No. D0410007).
文摘It has been reported that there is an interaction between Benzo[a]pyrene （BaP）, a widespread carcinogenic polycyclic aromatic hydrocarbon, and tributyltin （TBT）, an organometal used as an antifouling biocide. This study was therefore designed to examine the potential in vivo influence of BaP, TBT and their mixture on splenic antioxidant defense systems of Sebastiscus marmoratus. The fish were exposed to water containing environmentally relevant concentrations of BaP, TBT and their mixture. Spleens were collected for biochemical analysis after exposure for 7, 25, 50 d and after recovery for 7, 20 d. Cotreatment with BaP and TBT for 7 d potentiated the induction of glutathione peroxidase （GPx） activity by BaP or TBT alone. The cotreatment for 25 and 50 d resulted in inhibition of GPx activity, which was similar to the effect of TBT. Splenic glutathione S-transferase （GST） activities were significantly elevated in S. marmoratus exposed to BaP starting from 7 d and remained high up to 25 d. However, no further activity change was found with prolonged exposure. Cotreatment of BaP and TBT primarily inhibited the GST activity, which was similar to the effect of TBT. Cotreatment with BaP and TBT for 25 or 50 d potentiated the depletion of GSH （glutathione） by BaP or TBT alone. MDA （malondialdehyde） contents in spleen of S. marmoratus were not significantly altered compared with the control during the test period. Spleen, as an immune organ, is sensitive to exposure of BaP or TBT. It should have an effective mechanism to counteract oxidative damage. Antioxidative defense systems in spleen of S. marmoratus should be considered as potential biomarkers. Short-term exposure of BaP or TBT could result in induction of antioxidant defense system. A significant decrease of these indices, such as GSH, GST, GPx might indicate more severe contamination.
基金The National Basic Research Program (973) of China (No. 2004CB418506)the National Natural Science Foundation of China (No.20337010) the Hi-Tech Research and Development Program (863) of China (No. 2004AA649060)
文摘The rates of photodegradation and photocatalysis of benzo [a]pyrene （BaP） on soil surfaces under UV light have been studied. Different parameters such as temperature, soil particle sizes, and soil depth responsible for photodegradation, catalyst loads and wavelength of UV irradiation blamed for photocatalysis have been monitored. The results obtained indicated that BaP photodegradation follows pseudo-first-order kinetics. BaP photodegradation was the fastest at 30℃ . The rates of BaP photodegradation at different soil particle size followed the order： less than 1 mm〉less than 0.45 mm〉less than 0.25 mm. When the soil depth increased from 1 mm to 4 ram, the half-life increased from 13.23 d to 17.73 d. The additions of TiO2 or Fe2O3 accelerated the photodegradation of BaP, and the photocatalysis of BaP follows pseudo-first-order kinetics. Changes in catalyst loads of TiO2 （0.5%, 1%, 2%, and 3% （wt）） or Fe203 （2%, 5%, 7%, and 10% （wt）） did not significantly affect the degradation rates. Both BaP photocatalysis in the presence of TiO2 and Fe2O3 were the fastest at 254 nm UV irradiation.
文摘Seedling emergence tests were conducted in a meadow brown soil using five plant species(i.e., Chinese cabbage, green onion, tomato, turnip and wheat) to determine the phytotoxicity of phenanthrene, pyrene and their mixtures. The soil was amended with up to 1000 mg/kg soil of phenanthrene or 600 mg/kg soil of pyrene. Seedling emergence and root growth were measured. The results indicated that root elongation was more sensitive than seedling emergence. Root length decreased with increasing phenanthrene or pyrene concentrations(p≤0 05). Phenanthrene was more phytotoxic than pyrene. The lowest observable adverse effect concentration(LOAEC) was 10 mg/kg for phenanthrene when tested with green onion, and 50 mg/kg for pyrene when tested with wheat. Among the five species, wheat was found to be the most sensitive. When amended jointly at or below their respective LOAEC, phenanthrene and pyrene produced a synergistic toxic effect.
