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Binding of pyrene to dissolved organic matters: fractionation and characterization 被引量:5
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作者 DAIJing-yu ZHOUJiang-min QINShu-ping 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第6期928-933,共6页
Based on a modified Leenheer DOM fractionation scheme, fractionation of DOM from the paddy soil was conducted by using XAD-8 resin into hydrophobic bases(HOB), hydrophobic acids(HOA), acid-insoluble matter(AIM), hydro... Based on a modified Leenheer DOM fractionation scheme, fractionation of DOM from the paddy soil was conducted by using XAD-8 resin into hydrophobic bases(HOB), hydrophobic acids(HOA), acid-insoluble matter(AIM), hydrophobic neutrals(HON) and hydrophilic matter(HIM). In total carbon content of DOM, 35.32% were the HIM and only 0.73% the HOB. However, HOA and AIM altogether occupied 53.45%, while the HON fraction represented 10%. The sorption experiments were conducted to determine the sorption capacity of pyrene on unfractionated DOM and its fractions. Elemental analysis, 1H-NMR and FTIR spectra were carried out on unfractionated DOM and its fractions to examine the relationship between the structure of DOM and partition coefficients(K oc). The results showed that HON had a greater affinity for binding pyrene than other fractions. While HON was characterized by large long-chain alkylate (aliphatic structure). AIM exhibited relative higher K oc values than HOA and HIM, due to much aromatic structure in AIM, while the high content of carboxylic groups of HOA and HIM depressed their binding capacity. This study demonstrated HON is a key subcomponents of DOM in binding of pyrene, in other words, aliphalic structure in DOM play an important role in binding of pyrene. 展开更多
关键词 dissolved organic matter(DOM) PYRENE FRACTIONATION SORPTION
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Biochar-derived dissolved organic matters influencing bacterium characteristics during biodegradation of sulfamethoxazole and chloramphenicol under alternation of visible and avoiding light 被引量:1
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作者 Fang Yang Yanan Xue +3 位作者 Yue Gao Qing Zhu Cuiping Wang Hongwen Sun 《Biochar》 SCIE CAS CSCD 2023年第1期160-174,共15页
The influence of biochar-released dissolved organic matter(BDOM)on the transcription of gene(DEG)in Pseudomonas stutzeri and Shewanella putrefacien during sulfamethoxazole(SMX)and chloramphenicol(CAP)biodegradation un... The influence of biochar-released dissolved organic matter(BDOM)on the transcription of gene(DEG)in Pseudomonas stutzeri and Shewanella putrefacien during sulfamethoxazole(SMX)and chloramphenicol(CAP)biodegradation under visible light was investigated in this study.The results indicated that BDOM components would be nutrients for bacterial amplification and growth under the culture conditions of xenon lamp irradiation and avoiding light,especially BDOM from low temperatures.Additionally,visible light irradiation would improve the saturated fatty acid by stimulating the cell membrane of the microorganism,thus promoting the biodegradation of antibiotics through altering P.stutzeri and S.putrefaciens reoxidative and catabolism processes and significantly inhabiting the copy number of their genes.Moreover,the upregulated genes and enzymes related to SMX and CAP-metabolic and catabolic processes were enriched,which were involved in the pathways of biodegradation,further improving biodegradation efficiency.In particular,interaction network analysis between the top 100 dominant functional genes from P.stutzeri and S.putrefaciens and the molecular types of BDOM,e.g.,CHO,CHON,and CHOS(p<0.05),indicated that the genes of molecular function showed a high positive or negative correlation with the CHO type of BDOM.The results revealed that the CHO type of BDOM affected the functional genes of molecular function,cellular component,and biological process from P.stutzeri and S.putrefaciens,influencing the biodegradation of SMX and CAP.This study provided an basis for BDOM playing a role in antibiotic removal from the aqueous solution using biochar combined with photobiodegradation. 展开更多
关键词 Biochar-derived dissolved organic matters Molecular characteristics Antibiotics degradation Transcriptome Functional genes
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Straw mulching alters the composition and loss of dissolved organic matter in farmland surface runoff by inhibiting the fragmentation of soil small macroaggregates
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作者 Shanshan Cai Lei Sun +7 位作者 Wei Wang Yan Li Jianli Ding Liang Jin Yumei Li Jiuming Zhang Jingkuan Wang Dan Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1703-1717,共15页
Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How st... Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland. 展开更多
关键词 dissolved organic matter black soil surface runoff AGGREGATES fluorescence spectrum
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The impact of typhoons on the biogeochemistry of dissolved organic matter in eutrophic bays in northwestern South China Sea
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作者 Xuan Lu Qibin Lao +3 位作者 Fajin Chen Guangzhe Jin Chunqing Chen Qingmei Zhu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期15-31,共17页
Highly productive estuaries facilitate intense decomposition of dissolved organic matter(DOM) as a carbon source.However,the specific impacts of typhoons on DOM decomposition in eutrophic bays remain unclear.To addres... Highly productive estuaries facilitate intense decomposition of dissolved organic matter(DOM) as a carbon source.However,the specific impacts of typhoons on DOM decomposition in eutrophic bays remain unclear.To address this issue,we investigated the spectral characteristics of DOM before and after Typhoon Ewiniar in Zhanjiang B ay,a eutrophic semi-enclosed bay in the northwestern South China Sea.The results revealed that intense microbial decomposition of DOM occurred during the pre-typhoon period because high nutrient inputs facilitated the mobilization of DOM in the bay.However,the intrusion of external seawater induced by the typhoon diluted the nutrient levels in Zhanjiang B ay,reducing the impact of microbial decomposition on DOM during the post-typhoon perio d.Nevertheless,the net addition of DOM occurred in Zhanjiang Bay during the post-typhoon period,possibly because of the decomposition of particulate organic matter(POM) and desorption of particulate matter.In addition,an increase in apparent oxygen utilization,a decrease in DO saturation and the reduced level of Chl a indicated that organic matter(OM) decomposition was enhanced and OM decomposition shifted to POM decomposition in Zhanjiang Bay after the typhoon.Overall,our study highlighted the shift in the intense OM decomposition from DOM to POM decomposition before and after typhoons in eutrophic bays,providing new insights into the response of typhoons to biogeo chemistry. 展开更多
关键词 dissolved organic matter optical analyses decomposition TYPHOON northwestern South China Sea
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Impacts of Water-Sediment Regulation Scheme on Chromophoric Dissolved Organic Matter in the Lower Yellow River
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作者 LIU Xiao JIANG Xueyan +2 位作者 LIU Qian SUI Juanjuan ZOU Li 《Journal of Ocean University of China》 CAS CSCD 2024年第2期455-466,共12页
As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been c... As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water quality.Water-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water quality.Chromophoric dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human activities.Here,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during WSRS.In addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM compositions.Under the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS period.Sediment resuspension inhibits microbial activities and reduces the production of autochthonous CDOM.Overall,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment. 展开更多
关键词 chromophoric dissolved organic matter(CDOM) water-sediment regulation scheme(WSRS) Yellow River optical properties
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Impact of transparent exopolymer particles on the dynamics of dissolved organic carbon in the Amundsen Sea,Antarctica
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作者 HU Ji XUE Siyou +6 位作者 ZHAO Jun LI Dong ZHANG Haifeng YU Peisong ZHANG Cai YANG Xufeng PAN Jianming 《Advances in Polar Science》 CSCD 2024年第1期123-131,共9页
The Southern Ocean is an important carbon sink pool and plays a critical role in the global carbon cycling.The Amundsen Sea was reported to be highly productive in inshore area in the Southern Ocean.In order to invest... The Southern Ocean is an important carbon sink pool and plays a critical role in the global carbon cycling.The Amundsen Sea was reported to be highly productive in inshore area in the Southern Ocean.In order to investigate the influence of transparent exopolymer particles(TEP)on the behavior of dissolved organic carbon(DOC)in this region,a comprehensive study was conducted,encompassing both open water areas and highly productive polynyas.It was found that microbial heterotrophic metabolism is the primary process responsible for the production of humic-like fluorescent components in the open ocean.The relationship between apparent oxygen utilization and the two humic-like components can be accurately described by a power-law function,with a conversion rate consistent with that observed globally.The presence of TEP was found to have little impact on this process.Additionally,the study revealed the accumulation of DOC at the sea surface in the Amundsen Sea Polynya,suggesting that TEP may play a critical role in this phenomenon.These findings contribute to a deeper understanding of the dynamics and surface accumulation of DOC in the Amundsen Sea Polynya,and provide valuable insights into the carbon cycle in this region. 展开更多
关键词 dissolved organic matter chromophoric dissolved organic matter excitation-emission matrix coupled with parallel factor analysis transparent exopolymer particles Amundsen Sea ANTARCTICA
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Dissolved Organic Matter Features of Three Adjacent Eastern Mediterranean Urbanized Watersheds
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作者 Nour Abboud Elias Michel Maatouk +1 位作者 Zeinab Matar Veronique Kazpard 《Open Journal of Modern Hydrology》 CAS 2024年第3期153-173,共21页
Landscape urbanization broadly affects ecosystems in coastal watersheds, but, until now, the influence of nonpoint source urban inputs on dissolved organic matter (DOM) amount, composition, and source is poorly unders... Landscape urbanization broadly affects ecosystems in coastal watersheds, but, until now, the influence of nonpoint source urban inputs on dissolved organic matter (DOM) amount, composition, and source is poorly understood. To understand how DOM composition varied with urbanization, fluorescence excitation-emission matrices (EEMs) were determined for urban and non-urban waters from upstream to downstream sites along three adjacent coastal watersheds that flow into the Mediterranean Sea. Two humic DOM fluorescent components (humic-like and fulvic-like peaks) and two proteinic components (tyrosine-like and tryptophane-like peaks) were identified by EEM fluorescence. The results indicated that urbanization had an important influence on DOM concentration and composition, with urban waters having a high degree of DOM variation due to different land uses surrounding each body of water. Urban waters show a higher DOM fluorescence index (FI), the highest fluorescence intensity of protein-like manifested also by BIX values, and a lower value of the humification index (HIX) than non-urban waters which were dominated by allochthonous inputs. In addition, the EEM was compared in dry and wet season where higher DOM amounts and FI appeared in summer due to autochthonous production coming from algae growth compared to allochthonous input from rainfall dominated in wet season. The concentration of DOC increased from upstream to downstream for the three rivers, especially Beirut River. The increase in DOC values was observed in both dry and wet seasons by 39 and 19 times respectively compared to upstream (0.93 - 0.91 mgC/L). 展开更多
关键词 dissolved organic Matter DOM EEM Fluorescence Spectroscopy Autochthonous/Allochthonous DOM Urbanization Upstream/Downstream Wet/Dry Season
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Effects of pore size and dissolved organic matters on diffusion of arsenate in aqueous solution 被引量:3
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作者 Yulong Wang Shaofeng Wang +1 位作者 Xin Wang Yongfeng Jia 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第2期190-196,共7页
Presented here is the influence of membrane pore size and dissolved organic matters on the diffusion coefficient(D) of aqueous arsenate, investigated by the diffusion cell method for the first time. The p H-dependen... Presented here is the influence of membrane pore size and dissolved organic matters on the diffusion coefficient(D) of aqueous arsenate, investigated by the diffusion cell method for the first time. The p H-dependent diffusion coefficient of arsenate was determined and compared with values from previous studies; the coefficient was found to decrease with increasing p H, showing the validity of our novel diffusion cell method. The D value increased dramatically as a function of membrane pore size at small pore sizes, and then increased slowly at pore sizes larger than 2.0 μm. Using the Exp Assoc model, the maximum D value was determined to be 11.2565 × 10^-6cm^2/sec. The presence of dissolved organic matters led to a dramatic increase of the D of arsenate, which could be attributed to electrostatic effects and ionic effects of salts. These results improve the understanding of the diffusion behavior of arsenate, especially the important role of various environmental parameters in the study and prediction of the migration of arsenate in aquatic water systems. 展开更多
关键词 ARSENATE DIFFUSION PORE p H dissolved organic matters MIGRATION
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Probing the roles of pH and ionic strength on electrostatic binding of tetracycline by dissolved organic matters: Reevaluation of modified fitting model 被引量:3
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作者 Bo Yang Xin Cheng +3 位作者 Yongli Zhang Wei Li Jingquan Wang Hongguang Guo 《Environmental Science and Ecotechnology》 2021年第4期130-139,共10页
The binding performance of dissolved organic matters (DOM) plays a critical role in the migration,diffusion and removal of various residual pollutants in the natural water environment. In the currentstudy, four typica... The binding performance of dissolved organic matters (DOM) plays a critical role in the migration,diffusion and removal of various residual pollutants in the natural water environment. In the currentstudy, four typical DOMs (including bovine serum proteins BSA (proteins), sodium alginate SAA (polysaccharides), humic acid HA and fulvic acid FA (humus)) are selected to investigate the binding roles inzwitterionic tetracycline (TET) antibiotic under various ionic strength (IS ¼ 0.001e0.1 M) and pH (5.0e9.0). The dialysis equilibration technique was employed to determine the binding concentrations ofTET, and the influence of IS and pH on binding performance was evaluated via UVevis spectroscopy, totalorganic carbon (TOC), and Excitation-Emission-Matrix spectra (EEM), zeta potentials and molecule sizedistribution analysis. Our results suggested that carboxyl and phenolic hydroxyl were identified as themain contributors to TET binding based on the fourier transform infrared spectroscopy (FTIR) analysis,and the binding capability of four DOMs followed as HA > FA » BSA > SAA. The biggest binding concentrations of TET by 10 mg C/L HA, FA, BSA and SAA were 0.863 mM, 0.487 mM, 0.084 mM and 0.086 mM,respectively. The higher binding capability of HA and FA is mainly attributed to their richer functionalgroups, lower zeta potential (HA/FA ¼ 15.92/-13.54 mV) and the bigger molecular size (HA/FA ¼ 24668/27750 nm). IS significantly inhibits the binding interaction by compressing the molecular structure andthe surface electric double layer, while pH had a weak effect. By combining the Donnan model and themultiple linear regression analysis, a modified Karickhoff model was established to effectively predict thebinding performance of DOM under different IS (0.001e0.1 M) and pH (5.0e9.0) conditions, and the R2 oflinear fitting between experiment-measured logKDOC and model-calculated logKOC were 0.94 for HA and0.91 for FA. This finding provides a theoretical basis for characterizing and predicting the binding performance of various DOMs to residual micropollutants in the natural water environment. 展开更多
关键词 dissolved organic matters TETRACYCLINE Karickhoff model PH Ionic strength
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Three-dimensional fluorescence spectral characterization of soil dissolved organic matters in the fluctuating water-level zone of Kai County,Three Gorges Reservoir 被引量:5
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作者 Fang FANG Yan YANG +3 位作者 Jinsong GUO Hong ZHOU Chuan FU Zhe LI 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2011年第3期426-434,共9页
Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Mos... Three-dimensional fluorescence spectroscopy was used to investigate the fluorescent properties of soil dissolved organic matter(DOM)in the water-levelfluctuation zone(WLFZ)of Kai County,Three Gorges Reservoir(TGR).Most of the soil DOM analyzed in this study was found to contain four fluorescence peaks.Peaks A and C represent humic-like fluorescence,whereas peaks B and D represent tryptophan-like fluorescence.Peaks E and F,which represent tyrosine-like fluorescence,only appeared in certain soils.Soil humus was the main source of DOM in soil,and higher concentration of soil DOM was found in the exposed soil than submerged soil.Compared to the peaks A and B,the fluorescence intensities of peaks C and D were strongly influenced by the fluctuating water level.Analysis of fluorescence intensities of different peaks in soil DOM showed that WLFZ soil was not contaminated significantly.Soil DOM contained at least two types of humic-like fluorescence groups and two types of protein-like fluorescence groups.The proportion of the content of peak A in soil organic matter was quite stable.The soil DOM in exposed soil had relatively high humification and aromaticity,and periodic submerging and exposure of soil had an impact on the humification of soil DOM. 展开更多
关键词 water-level-fluctuation zone(WLFZ) SOIL dissolved organic matter(DOM) three-dimensional fluorescence spectra
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Spatiotemporal characteristics and remote sensing estimation of colored dissolved organic matter around the Leizhou Peninsula
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作者 Dongyang FU Shiyun WEI +3 位作者 Guo YU Yafei LUO Huabing XU Zhaoguang CHEN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第4期1405-1424,共20页
Colored dissolved organic matter(CDOM)is an important optically active substance in marine environment.Its biochemical conservatism makes it an important indicator to offshore pollution process.Monitoring the content,... Colored dissolved organic matter(CDOM)is an important optically active substance in marine environment.Its biochemical conservatism makes it an important indicator to offshore pollution process.Monitoring the content,composition,and diffusion process of CDOM is a good approach to analyze the terrestrial input,optical properties,and ecological environment of offshore areas.The spatiotemporal characteristics of CDOM around the Leizhou Peninsula were analyzed based on field observation data collected in the autumn 2020 and spring 2021,and an empirical inversion model of the ag(355)(absorption coefficient at 355 nm)and spectral slope(Sg)(g stands for gelbstoff/gilvin,which is called CDOM)based on Sentinel-3A ocean and land color instrument(OLCI)images was constructed.The results show(1)the order of average ag(355)value around the Leizhou Peninsula was east coast(0.503/m)>Qiongzhou Strait(0.502/m)>west coast(0.365/m);(2)the best band combinations of CDOM inversion in spring and autumn were(B4+B11)/B3 and(B7-B1)/B6(B stands for the band of spectral images),and the final inversion results are close to the measured results,indicating that the model has good accuracy;(3)the S_(g)value of the CDOM absorption spectrum was fitted to the hyperbolicexponential model.The fitting accuracy of the model was higher than those of the exponential model and the hyperbolic model,and the best S_(g)inversion model was constructed by selecting Sg(275-295)and Sg(250-295)in spring and autumn;(4)the spatial distributions of ag(355)and S_(g)were inverted,and CDOM in the waters around the Leizhou Peninsula originated from terrestrial organic matter carried by coastal aquaculture zones and runoff in the northeast Zhanjiang and the northern Beibu Gulf. 展开更多
关键词 colored dissolved organic matter(CDOM) ocean and land color instrument(OLCI) spectral slope hyperbolic-exponential model INVERSION
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Seasonal Distribution of Observed Colored Dissolved Organic Matter(CDOM)in the Eastern Indian Ocean
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作者 CAI Xiaoqing MENG Jie +6 位作者 YUAN Chao LIU Rongjie HOU Erhu BI Dayong LI Yaoru QIAN Chengcheng ZHONG Shan 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第4期886-896,共11页
Colored dissolved organic matter(CDOM)is a crucial constituent that affects the optical absorption properties of seawater.Owing to the relatively limited measured data on the spatial distribution characteristics of CD... Colored dissolved organic matter(CDOM)is a crucial constituent that affects the optical absorption properties of seawater.Owing to the relatively limited measured data on the spatial distribution characteristics of CDOM in the tropical eastern Indian Ocean,this study analyzes the optical absorption characteristics of CDOM in the southeast Indian Ocean using the data collected during four seasons from 2013 to 2017.This work also systematically describes the seasonal horizontal and vertical distribution characteristics of CDOM in this area and conducts a preliminary analysis of the relevant factors affecting CDOM absorption characteristics in this region.Results indicate that the CDOM ag(440)during summer was remarkably lower than that in the coastal waters of Europe and coastal waters of China but slightly higher than that in the western and southeast Pacific.The spatial distribution of surface CDOM shows remarkable seasonal differences,and the spatial distribution characteristics of CDOM in the 5°S,92°E region differ between spring/summer and autumn/winter.The values of ag(400)and ag(440)are weak/strong at a surface/subsurface level of 100 m,with differences found between summer and winter.The correlation of CDOM with temperature,salinity,and chlorophyll-a concentration is relatively low,indicating that CDOM is an independent driving mechanism influenced by phytoplankton degradation,photobleaching,and water mixing. 展开更多
关键词 colored dissolved organic matter tropical eastern Indian Ocean distribution characteristics influencing factors
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Bioactivity profile of dissolved organic matter and its relation to molecular composition
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作者 Teresa S.Catalá Linn G.Speidel +2 位作者 Arlette Wenzel-Storjohann Thorsten Dittmar Deniz Tasdemir 《Natural Products and Bioprospecting》 CSCD 2023年第1期425-440,共16页
Dissolved organic matter(DOM)occupies a huge and uncharted molecular space.Given its properties,DOM can be presented as a promising biotechnological resource.However,research into bioactivities of DOM is still in earl... Dissolved organic matter(DOM)occupies a huge and uncharted molecular space.Given its properties,DOM can be presented as a promising biotechnological resource.However,research into bioactivities of DOM is still in early stages.In this study,the biotechnological potential of terrestrial and marine DOM,its molecular composition and their relationships are investigated.Samples were screened for their in vitro antibacterial,antifungal,anticancer and antioxidant activities.Antibacterial activity was detected against Staphylococcus aureus in almost all DOM samples,with freshwater DOM showing the lowest IC50 values.Most samples also inhibited Staphylococcus epidermidis,and four DOM extracts showed up to fourfold higher potency than the reference drug.Antifungal activity was limited to only porewater DOM towards human dermatophyte Trichophyton rubrum.No significant in vitro anticancer activity was observed.Low antioxidant potential was exerted.The molecular characterization by FT-ICR MS allowed a broad compositional overview.Three main distinguished groups have been identified by PCoA analyses.Antibacterial activities are related to high aromaticity content and highly-unsaturated molecular formulae(O-poor).Antifungal effect is correlated with highly-unsaturated molecular formulae(O-rich).Antioxidant activity is positively related to the presence of double bonds and polyphenols.This study evidenced for the first time antibacterial and antifungal activity in DOM with potential applications in cosmeceutical,pharmaceutical and aquaculture industry.The lack of cytotoxicity and the almost unlimited presence of this organic material may open new avenues in future marine bioprospect-ing efforts. 展开更多
关键词 dissolved organic matter Antibacterial activity Antifungal activity Antioxidant activity Molecular composition
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Photodegradation of chromophoric dissolved organic matters in the water of Lake Dianchi, China 被引量:2
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作者 Yuan ZHANG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第4期575-582,共8页
Water samples were taken from Lake Dianchi, on the Yungui Plateau of southwest China, and experi- ments were conducted to simulate the photochemical degradation characteristic of chromophoric dissolved organic matter ... Water samples were taken from Lake Dianchi, on the Yungui Plateau of southwest China, and experi- ments were conducted to simulate the photochemical degradation characteristic of chromophoric dissolved organic matter (CDOM) in the lake water. Three groups of experiments under different light conditions: ultraviolet (UV) light, visible light, and dark, were done and variations of fluorescence properties, UV absorbance, and dissolved organic carbon (DOC) concentrations during the experiments were analyzed to study the photodegradation process of CDOM with time. The result showed that light irradiation led to significant photochemical degradation of CDOM, resulting in changes in florescent properties, absorbance losses, decreases in aromaticity and average molecular weight, as well as decline in DOC concentration in the water. It was also observed that UV irradiation had greater effect than visible light did. However, various fluorophores had different sensitivities to the same irradiation condition, that is, protein-like fluorophore at the low excitation wavelengths is more sensitive to UV irradiation than the other fluorophores, and is more readily to undergo photo-degradation. In addition, visible light irradiation did not have significant impact on DOC in the water, with DOC concentration decrease by 5.57% -59.9% during the experiment time. These results may provide new knowledge on the environment behavior of CDOM in the water of Lake Dianchi. 展开更多
关键词 chromophoric dissolved organic matter photodegradation ultraviolet radiation dissolved organic carbon
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Analysis and Pollution Assessment on the Dissolved Organic Matter in the Sediment of Hydro-fluctuation Belt(Yunyang Part) 被引量:2
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作者 来守军 关晓琳 +3 位作者 陈飞 蒋琴 莫谍谍 付川 《Meteorological and Environmental Research》 CAS 2010年第8期98-101,共4页
By using the ultraviolet absorption spectrum,the fluorescence spectrum and three dimensional fluorescence spectra,the composition of dissolved organic matter(DOM) and the humification degree,etc.in the sediment of hyd... By using the ultraviolet absorption spectrum,the fluorescence spectrum and three dimensional fluorescence spectra,the composition of dissolved organic matter(DOM) and the humification degree,etc.in the sediment of hydro-fluctuation belt(Yunyang part) were analyzed.The relationship between the test parameters and the pollution degree in the region was discussed.The research results of UV spectrum data E3/E4 showed that in 4 sampling sites which included Huangshi Town,Gaoyang Town,Shuangjiang Town and Quma Town,the humification degree in the sediment of hydro-fluctuation belt in Shuangjiang Town sampling site was lower,and the aromaticity was smaller.Moreover,the effect of human factor was comparatively smaller.The fluorescence index value which represented the source of humus in DOM was 1.62-1.88.It showed that the biological and terrestrial source both existed.Three dimensional spectra results showed that the pollution degrees in 4 sampling sites were all smaller,and some prevention measures should be taken early. 展开更多
关键词 Hydro-fluctuation belt SEDIMENT dissolved organic matter Analysis and assessment China
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Characterization of dissolved organic matter fractions from Lake Hongfeng, Southwestern China Plateau 被引量:65
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作者 WANG Liying WU Fengchang +2 位作者 ZHANG Runyu LI Wen LIAO Haiqing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第5期581-588,共8页
With XAD-series and ion exchange resins, dissolved organic matter (DOM) from Lake Hongfeng in Southwestern China Plateau was isolated into 6 fractions, i.e., humic acid (HA), fulvic acid (FA), hydrophobic neutra... With XAD-series and ion exchange resins, dissolved organic matter (DOM) from Lake Hongfeng in Southwestern China Plateau was isolated into 6 fractions, i.e., humic acid (HA), fulvic acid (FA), hydrophobic neutrals (HON), hydrophilic acids (HIA), hydrophilic bases (HIB) and hydrophilic neutrals (HIN). Those fractions were characterized by high performance size exclusion chromatography, fluorescence spectroscopy and UV absorbance. Among the 6 fractions, FA was predominant and accounted for 51% of the total DOM. The weight-average (Mw) and number-averaged (Mn) molecular weight of these fractions ranged from 1688 to 2355 Da and from 1338 to 1928 Da, respectively. A strong correlation was observed between specific UV absorbance at 280 nm, E2/E3 (absorbance at 250 nm to 365 nm), and the molecular weight for DOM fractions. UV-Vis fulvic-like fluorescence peaks were found in all fractions. Proteinlike fluorescence peaks existed in HON may indicate that microbial activity was severely in Lake Hongfeng. There was a significant relationship between fluorescence intensities and specific UV absorbance at 254 nm for those DOM fractions, suggesting their similar luminescence characteristics. The values of fluorescence index (f450/500) indicated that hydrophobic fractions may derive from terrestrial sources, and the hydrophilic fractions from microbial and terrestrial origins. Those results suggest that there were inter-relationships between molecular weight, fluorescence and absorbance characteristics, and also subtle consistencies between the hydrophilic and hydrophobic properties and the sources for these 6 fractions from Lake Hongfeng. 展开更多
关键词 dissolved organic matter FRACTIONATION molecular weight UV absorbance fluorescence spectroscopy
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Characteristics of dissolved organic matter(DOM) in leachate with different landfill ages 被引量:55
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作者 HUO Shouliang XI Beidou +3 位作者 YU Haichan HE Liansheng FAN Shilei LIU Hongliang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第4期492-498,共7页
The main objective of the study was to investigate the characteristics of dissolved organic matter (DOM) in leachate with different landfill ages through the chemical, spectroscopic, and elemental analysis. Humic ac... The main objective of the study was to investigate the characteristics of dissolved organic matter (DOM) in leachate with different landfill ages through the chemical, spectroscopic, and elemental analysis. Humic acid (HA), fulvic acid (FA), and hydrophilic (HyI) fractions were isolated and purified by the XAD-8 resin combined with the cation exchange resin method. The analytical results of fluorescence excitation-emission matrix spectroscopy (EEMs) revealed that the fluorescence peaks were protein-like fluorescence for young landfill leachate, while the fluorescence peaks for medium and old landfill leachate were humic-like and fulvic-like fluorescence, respectively. Elemental analysis showed that carbon, hydrogen, and nitrogen content decreased with landfill age, while the oxygen content increased. Moreover, the nitrogen content in these isolated fractions followed: HA 〉 HyI 〉 FA. The results of elemental analysis, FT-IR, and fluorescence EEMs also confirmed that aromatic carbons and portions of aliphatic functional groups were more abundant in leachate samples with increasing landfill age. 展开更多
关键词 dissolved organic matter (DOM) fluorescence EEMs DOM fractionafion LANDFILL LEACHATE
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Cadmium transport mediated by soil colloid and dissolved organic matter:A field study 被引量:25
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作者 Zhaoli Li, Lixiang Zhou College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, China. 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2010年第1期106-115,共10页
This study investigated the potential role of soil colloids and dissolved organic matter (DOM) in transporting Cd through in situ undisturbed paddy soil monoliths. Brilliant Blue was used as a tracer to assess the e... This study investigated the potential role of soil colloids and dissolved organic matter (DOM) in transporting Cd through in situ undisturbed paddy soil monoliths. Brilliant Blue was used as a tracer to assess the effect of preferential flow on Cd down migration. Experimental results showed that deep penetration of Cd and Brilliant Blue into the soil profile took place due to the preferential flow through macropores, mainly earthworm channels, with much of chemicals thus bypassing the soil matrix. Dye tracer and Cd distribution within the soil matrix was fairly restricted to several centimeters. Colloid restrained the migration of both dye and Cd in the matrix and preferential flow area. DOM facilitated the transport of Cd and Brilliant Blue in matrix and macropores by about 10 cm over that of the control. Pearson's is correlation analysis revealed strong associations between Brilliant Blue concentrations, exchangeable Cd and total Cd concentrations in three studied plots indicating that they had taken the same preferential flow pathway. 展开更多
关键词 COLLOID dissolved organic matter preferential flow dye tracer
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Effect of dissolved organic matter on adsorption and desorption of mercury by soils 被引量:24
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作者 YANG, Yongkui LIANG, Li WANG, Dingyong 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第9期1097-1102,共6页
Effects of dissolved organic matter (DOM) on adsorption and desorption of Hg were investigated in two kinds of soils, Xanthi-Udic Ferralosols (XUF) and Typic Purpli-Udic Cambosols (TPUC). The DOM was obtained from hum... Effects of dissolved organic matter (DOM) on adsorption and desorption of Hg were investigated in two kinds of soils, Xanthi-Udic Ferralosols (XUF) and Typic Purpli-Udic Cambosols (TPUC). The DOM was obtained from humus soil (DOMH), rice straw (DOMR), and pig manure (DOMP). The presence of DOM obviously reduced Hg maximum adsorption capacity with up to 40% decreases over the control, being an order of DOMH (250.00 mg/kg)< DOMR (303.03 mg/kg) < DOMP (322.58 mg/kg) < CK (control 416.67 mg/kg) for the... 展开更多
关键词 mercury (Hg) dissolved organic matter (DOM) adsorption DESORPTION
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Effects of long-term green manure application on the content and structure of dissolved organic matter in red paddy soil 被引量:22
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作者 GAO Song-juan GAO Ju-sheng +4 位作者 CAO Wei-dong ZOU Chun-qin HUANG Jing BAI Jinshun DOU Fu-gen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第8期1852-1860,共9页
Dissolved organic matter(DOM) plays important roles in soil biogeochemistry activity and nutrients transportation in soils, but studies regarding the long-term effects of green manures on the content and structure of ... Dissolved organic matter(DOM) plays important roles in soil biogeochemistry activity and nutrients transportation in soils, but studies regarding the long-term effects of green manures on the content and structure of DOM in red paddy soil have not been reported yet. A long-term green manure experiment established in 1982 was utilized to test the DOM contents in different treatments, and the spectral characteristics of DOM were investigated by using ultraviolet-visible(UV-Vis) spectrometry and Fourier transform infrared(FTIR) spectrometry. The experiment included four cropping systems: ricerice-milk vetch(RRV), rice-rice-rape(RRP), rice-rice-ryegrass(RRG) and rice-rice-winter fallow(RRF), among them, milk vetch, rape, and ryegrass are popular winter green manure species in southern China. The results showed that the content of dissolved organic carbon(DOC), which is widely used to estimate the concentration of DOM, was significantly promoted after the incorporation of green manures compared with the other sampling stages. The contents of aromatic groups and the degree of humification of DOM increased in RRV and RRP, suggesting more complex compositions of the soil DOM after long-term application of milk vetch and rape. The contents of phenol, alcohol and carboxylic acid group at the mature stage of early rice were significantly higher than those at the stage of after green manures turned over, especially for the RRV treatment. The absorption ratio of FTIR indicated that winter plantation of rape increased the aromatic-C/aliphatic-C ratio, and ryegrass increased the aromatic-C/carboxyl-C ratio. In conclusion, long-term planting of milk vetch and rape as green manures increased the degree of aromaticity, humification and average molecular weight of DOM, and made the DOM more stable in red paddy soil. 展开更多
关键词 green manure red paddy soil dissolved organic matter ultraviolet-visible spectra Fourier transform infrared spectra
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