Frontiers in Microbiology
·
2016
·
IF 4.165
Gu Haiping,Lou Jun,Wang Haizhen,Yang Yu,Wu Laosheng,Wu Jianjun,Xu Jianming
Reducing phenanthrene (PHE) in the environment is critical to ecosystem and human health. Biodegradation, biosorption, and the trans-membrane transport mechanism of PHE by a novel strain, Massilia sp. WF1, and an extensively researched model fungus, Phanerochaete chrysosporium were investigated in aqueous solutions. Results showed that the PHE residual concentration decreased with incubation time and the data fitted well to a first-order kinetic equation, and the t1/2 of PHE degradation by WF1, spores, and mycelial pellets of P. chrysosporium were about 2 h, 87 days, and 87 days, respectively. The biosorbed PHE was higher in P. Chrysosporium than that in WF1, and it increased after microorganisms were inactivated and inhibited, especially in mycelial pellets. The detected intracellular auto-fluorescence of PHE by two-photon excitation microscopy also proved that PHE indeed entered into the cells. Based on regression, the intracellular (Kdin) and extracellular (Kdout) dissipation rate constants of PHE by WF1 were higher than those by spores and mycelial pellets. In addition, the transport rate constant of PHE from outside solution into cells (KinS/Vout) for WF1 were higher than the efflux rate constant of PHE from cells to outside solution (KoutS/Vin), while the opposite phenomena were observed for spores and mycelial pellets. The amount of PHE that transported from outside solution into cells was attributed to the rapid degradation and active PHE efflux in the cells of WF1 and P. Chrysosporium, respectively. Besides, the results under the inhibition treatments of 4°C, and the presence of sodium azide, colchicine, and cytochalasin B demonstrated that a passive trans-membrane transport mechanism was involved in PHE entering into the cells of WF1 and P. Chrysosporium.
研究领域:
环境生物学
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微生物学
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DOI
PubMed
高影响因子
Foods
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2023
·Vol. 12
·期 8
·1588
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IF 5.2
Jiaqi Luo,Siyu Liu,Hongyun Lu,Qihe Chen,Ying Shi
Soybeans possess unexpected flavors and are difficult to be absorbed by the gastrointestinal tract. Kefir grain fermentation provides diverse strains and bioactive compounds, which may enhance flavor and bioaccessibility. Third-generation sequencing was applied to analyze the microbial diversity in milk and soybean kefir grains in this study. In both types of kefir grains, the most common bacterial genus wasLactobacillus, and their fungal communities were dominated byKazachstania.Lactobacillus kefiranofacienswas the most abundant species in kefir grains, whileLactobacillus kefirishowed a higher proportion in soybean kefir grains. In addition, the quantification of free amino acids and volatile flavor compounds in soybean solution and soybean kefir have shown the increased content of glutamic acid and a decreased amount of unpleasant beany flavor compounds, demonstrating that the nutritive value and sensory properties of soybean can be improved by kefir grain fermentation. Finally, the bioconversion of isoflavones during fermentation and in vitro digestion was evaluated, suggesting that fermentation is beneficial for aglycone formation and absorption. To conclude, kefir fermentation is proposed to change the microbial structure of kefir grains, promote the nutritional value of soybean-based fermented products, and provide possible solutions for the development of soybean products.Keywords:soybean;kefir grains;third-generation sequencing;fermentation;isoflavones
研究领域:
食品科学
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微生物学
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营养学
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DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
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2019
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IF 3.371
Xiaoqiang Jia,Yun He,Dawei Jiang,Chang Liu,Wenyu Lu
Polycyclic aromatic hydrocarbons (PAHs) like phenanthrene are harmful to human health and are difficult to eliminate from environments. In this study, a phenanthrene degrading strain, Pseudomonas aeruginosa PH1, was isolated from oil-contaminated soil. An engineered co-culture consortium was subsequently constructed comprising two engineered bacterial strains, Escherichia coli HY1 and P. aeruginosa PH2, for use in phenanthrene bioremoval. E. coli HY1 harbored two modules of terminal dioxygenases and an electron transfer chain, while P. aeruginosa PH2 contained a module of catechol 1,2-dioxygenase. Phenanthrene removal rates by the wild-type degrader, P. aeruginosa PH1, were 45%, 43%, and 81%, in mineral salt medium supplemented with 100 mg/L phenanthrene, 100 mg/L phenanthrene and 2% (wt/vol) oil, and 100 mg/L phenanthrene and 2% (vol/vol) n -hexadecane, respectively. In contrast, the engineered co-culture consortium removed 71%, 80%, and 88% of the phenanthrene in the corresponding treatments, thus achieving much higher removal efficiencies. Moreover, gas chromatography-mass spectrometry confirmed that the engineered co-culture consortium first oxidized phenanthrene to 9,10-dihydroxy phenanthrene and 1,2-dihydroxy phenanthrene and then metabolized these intermediates via catechol to carbon dioxide and water. During this process, E. coli HY1 dominated the initial oxidation steps, while P. aeruginosa PH2 was primarily responsible for ring cleavage. These results indicate that the engineered co-culture consortium described here represents a potential alternative and attractive means to remove PAHs from natural environments.
研究领域:
环境微生物学
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生物修复
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代谢工程
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DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
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2020
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IF 6.551
Kaihang Xu,Yindan Zhang,Yumei Huang,Jun Wang
The toxicology of microplastics in combination with other pollutants has attracted widespread attention. In this study, zebrafish were exposed to 3 mg/L polystyrene microplastic, 0.2 mg/L phenanthrene, and a combination of both. Zebrafish microplastic uptake, phenanthrene accumulation, antioxidant-associated enzyme activity and related gene expression, immune-associated gene expression, and the gut microflora were measured after 12 and 24 days of exposure. Phenanthrene and microplastic accumulation increased with exposure time and was also greater in the combined exposure group than in the single exposure group. Combined analysis of antioxidant enzyme activity and immune and antioxidant-related genes shows that exposure alone causes oxidative stress in zebrafish, ultimately increasing immunity and the expression of oxidative stress genes, while combined exposure exacerbates these changes. Fusobacteria decreased and Proteobacteria and Bacteroidetes increased in the three exposure groups of gut microorganisms. Overall, our study demonstrates that microplastics enhance the toxicity of phenanthrene and that the two have a synergistic effect.
研究领域:
环境毒理学
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水生生物学
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分子生物学
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Xiupeng Yue,Yaping Zhang,Yongping Shan,Kai Shen,Wentao Jiao
Electrokinetic transport followed by electrical resistance heating activation of peroxydisulfate is a novel in situ soil remediation method. However, the strategy of electrokinetic transport coupled with electrical resistance heating and the comprehensive evaluation of restored soil need to be further explored. In this study, a lab-scale simulation device for in situ electrokinetic transport coupled with electrical resistance heating activation of peroxydisulfate was constructed to monitor the transport and transfer of peroxydisulfate, target pollutants, and process parameters, and the physicochemical properties and bacterial community of treated soil were evaluated. The results showed that adding 10 wt% peroxydisulfate to both the anode and cathode resulted in the optimized transfer rate and cumulative concentration of peroxydisulfate under electrokinetics. After 8 h, the cumulative concentration of peroxydisulfate reached 66.15– 166.29 mmol L −1 , which was attributed to the migration of a large amount of S 2 O 8 2− from the cathode to the soil under electromigration . Additionally, the anodic interfacial electric potential was improved, which was more conducive to electroosmotic transport of peroxydisulfate from the anode chamber. By alternating electrokinetic transport and electrical resistance heating activation of peroxydisulfate for two cycles, the phenanthrene degradation efficiency in four evenly distributed wells between electrodes reached 75.4 %, 87.6 %, 92.3 %, and 94.4 %. With slight variations in soil morphology and structure, the electrokinetic transport coupled with electrical resistance heating activation of peroxydisulfate elevated the soil fertility index. The abundance and diversity of bacterial communities in treated soil recovered to above the original soil level after 15 days. Our findings may support the application of electrokinetic transport coupled with electrical resistance heating activation of peroxydisulfate as a promising green ecological technology for the in situ remediation of organic-contaminated soil.
研究领域:
环境科学
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土壤化学
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微生物学
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可持续技术
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DOI
PubMed
高影响因子
PROCESS BIOCHEMISTRY
·
2021
·
IF 3.757
Kun Xiao,Rennv Wang,Congyang Liu,Meini Wang,Wei Dong,Tao Pan
PAH biodegradation aided by surfactants and cyclodextrins has been widely studied because the former's micelles and the latter's hydrophobic cavities can increase the apparent solubility of PAHs. In this work, the effects of Triton X-100 (TX-100) and β-cyclodextrin (β-CD) on the bioavailability and biodegradation of phenanthrene (PHE) were investigated. The degrading microorganism used was Moraxella osloensis CFP312, a new strain screened from polluted soil and could form biofilms on crystalline PHE. At the same concentrations, β-CD solubilized less PHE than TX-100 but promoted PHE biodegradation. The two solubilizers had almost no different effects on CFP312 hydrophobicity; however, β-CD significantly eluted fewer cells from biofilms on crystalline PHE than TX-100. Microscopy observation revealed that the residual structure of the biofilm treated with β-CD was more complete than that of the biofilm treated with TX-100. This effect is beneficial to the function of biofilms and conducive to mass transfer from the exposed area in the crystalline PHE to the aqueous phase. Although TX-100 and β-CD could enhance the mass transfer of PHE to the aqueous phase, the latter significantly improved the bioavailability and biodegradation of PHE mainly because its solubilization was accompanied by easy desorption and retention of the biofilm functional integrity.
研究领域:
环境科学
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微生物学
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DOI
高影响因子
ANALYTICAL SCIENCES
·
2017
·Vol. 33
·期 1
·23-27
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IF 1.228
Wang Liang,Zhang Yi,Park Yeonju,Chen Lei,Jung Young Mee
Iii this paper, we demonstrate a new promising resonance Raman (RR)-based method for the determination of Fe 3+ concentrations in aqueous solutions. Iron ions were quantified at a low concentration range by employing hydroxylamine hydrochloride as the reductant, and phenanthroline as the complexing agent, (hereby reducing Fe 3+ to Fe 2+ . The addition of Fe 3+ to the detection reagent resulted in a rapid color change from colorless to orange-red. together with an obvious new RR band appearing at 1459 cm −1 . Herein, the RR intensity of the phenanthroline-Fe 2+ complex strengthened with increasing Fe 3+ concentration, which was identified from the variation of the Raman spectra. Therefore, we successfully detected Fe 3+ at lower concentrations using the proposed method, illustrating its great potential for the detection of Fe 3+ with abundant RR fingerprint information. More importantly, the proposed method exhibited a wide liner range from 0.05 to 10 μg/mL.
研究领域:
分析化学
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环境科学
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DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Taiguang Li,Mingyong Wang,Qingzheng Hou,Yaqi Hou,Kai Xuan,Yongmei Hao
One kind of novel magnetically separable graphene-based titanium dioxide photocatalytic nano-adsorbents (GO-FSNTs) were prepared for the adsorption-photodegradation of phenanthrene under visible light. The GO-FSNTs displayed the high adsorption-photodegradation efficiency and 10 mg of 0.6% GO-FSNT (wt%) can remove 94.9% of phenanthrene within 4 h. The introduction of a small amount of GO enables 0.6% GO-FSNT to selectively adsorb phenanthrene through the π-π interaction, reduce the light-shielding effect and improve separation of photogenerated carriers effectively. Meanwhile, the N-TiO 2 shell is occupied by adsorbed water molecules which can spontaneously repair lattice oxygen. Furthermore, the more hydrophilic surface of 0.6% GO-FSNT is formed by increased photoinduced hydroxyl groups under visible light during photodegradation. The photoinduced hydroxyl groups can further generate OH and improve photocatalytic activity. The degradation pathway of phenanthrene was proposed based on intermediates analysis and density functional theory calculations. This work helps to reveal the relationship between the adsorption-photodegradation and the photoinduced hydrophilicity.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Jun Qin,Xiaomei Li,Zezhong Chen,Feng Feng
Commercially available 9-bromophenanthrene (9-BrP) was used as fluorescence probe for determination of trace palladium (Pd). Under the catalysis of Pd 2+ , 9-BrP is converted to phenanthrene, which can emit stronger fluorescence. Consequently, fluorescence of Pd sample is greatly enhanced, and the enhancement is positively correlated with the concentration of Pd 2+ . The catalytic reaction exhibits excellent selectivity and specificity, which enables a simplification on the pre-treatment of real sample. The method has a wide linear range of 0.07–18 μM and a detection limit of 50 nM for Pd 2+ . Detection and recovery experiments of Pd in lake water, Pd-carbon catalyzer and surface soil are also satisfactory, indicating that the method has better feasibility and application potential in routine determination of Pd.
研究领域:
分析化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2019
·
IF 3.78
Siqi Huo,Zhitian Liu,Chuan Li,Xiaolei Wang,Haopeng Cai,Jun Wang
A flame-retardant curing agent (DTA) for epoxy resin (EP), which was constructed by phosphaphenanthrene and benzimidazole groups, was successfully synthesized via one-pot reaction between 2-aminobenzimidazole, terephthalaldehyde, and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). DTA induced the decomposition of EP matrix and promoted the carbonization at high temperature. As expected, DTA endowed EP thermoset with excellent flame retardancy and smoke suppression. For instance, EP/DDS/DTA-0.5 sample containing only 0.5 wt% phosphorus passed UL94 V-1 rating and its LOI value increased to 34.2%. In addition, the pk-HRR, av-HRR, THR, TSR, and TSP of EP/DDS/DTA-1.0 sample were decreased by 56.6%, 31.6%, 34.4%, 24.6% and 24.6% in comparison to those of EP/DDS sample. The flame retardant mechanism showed that the decomposition products of DTA played an important role in the formation of a compact and intumescent char layer in condensed phase. Meanwhile, the phosphorus-containing and nitrogen-containing fragments, which was generated by the pyrolysis of DTA, quenched the active free radicals and diluted the fuels in gaseous phase. Therefore, DTA exerted flame retardant effect in condensed and gaseous phases during combustion.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Xiaoxiao Tao,Huajun Duan,Wenjing Dong,Xin Wang,Shuang Yang
An intrinsic flame retardant vinyl ester TGIC-AA-DOPO constructed by phosphaphenanthrene and triazine-trione groups was successfully synthesized via the reaction between 1,3,5-triglycidyl isocyanurate (TGIC), acrylic acid and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO). The structure of TGIC-AA-DOPO was characterized in detail by fourier transform infrared spectroscopy (FTIR), 1 H and 31 P nuclear magnetic resonance (NMR) and liquid chromatography-high resolution mass spectrometry (LC-HRMS). The intrinsic P-N-containing flame retardant vinyl ester resin (IFR-VER) was prepared after diluting TGIC-AA-DOPO with styrene (st) and triallyl isocyanurate (TAIC). The flame retardancy, thermal properties and combustion behavior of IFR-VER were respectively investigated by a series of tests involving limited oxygen index (LOI) measurement, UL-94 vertical burning test, cone calorimeter test, thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The results showed that the as-obtained resin system exhibited a dramatic improvement in flame retardance. In the case of 40 wt% TAIC in resin system, the LOI value achieved 31%, leading to the UL-94 V-0 rating. In addition, compared with the 901-VER, the peak heat release rate (pk-HRR), average of heat release rate (av-HRR), total heat release (THR) and average effective heat of combustion (av-EHC) of the IFR-VER containing 40% TAIC diluent were decreased by 48%, 60%, 41% and 24% respectively. The diphase flame retardant effect of the prepared IFR-VER during combustion was demonstrated by the results of Py-GC/MS, FTIR, laser raman spectroscopy and scanning electron microscope (SEM).
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART B-ENGINEERING
·
2022
·
IF 11.322
Lei Zhang,Zhi Li,Qing-Qing Bi,Lin-Yun Jiang,Xiao-Die Zhang,En Tang,Xue-Meng Cao,Hong-Fang Li,Jose Hobson,De-Yi Wang
The synchronized improvement of strength , toughness and fire suppression poses to be a critical trade-off issue towards high-performance epoxy resin. Aiming to impart epoxy with balanced multifunctional improvement, the Schiff base-derived bio-based phosphaphenanthrene small-molecule reinforcer towards in-situ constructed Diels-Alder network within existing 3D network was proposed. The incorporation of 3.5 wt% reinforcer (CQ-DOPO) concurrently enhanced the tensile and impact strength of epoxy by 26.6% and 48.4% without visible deterioration of transparency. The increment of glass transition temperature by 14 °C via dynamic mechanical analysis was observed. The underpinning experimental and simulation investigation verified the proof of concept of in-situ formed Diels-Alder sacrificing network towards higher crosslinking density and strong-weak dual network. Raman spectra witnessed the breaking of sacrificing bond during fracture. Moreover, 3.5 wt% CQ-DOPO with an ultralow phosphorous loading of 0.245 wt% enabled to impart epoxy with UL-94 V-0 rating as well as limiting oxygen index of 32.0%. The multi-scale dual-phase analysis unveiled the synchronized suppression of fire reactions in vapor phase via PO· quenching as well as in condensed phase via char microstructure optimization. Hence, the rational strategy via in-situ construction of Diels-Alder sacrificing bond toward dual network exploits a novel roadmap for high-performance epoxy.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）