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Biodegradation of indole by a newly isolated Cupriavidus sp. SHE

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Journal of environmental sciences 2015年第8期27卷 126-132页

作者： Yuanyuan Qu E.Shen Qiao Ma Zhaojing Zhang Ziyan Liu Wenli Shen Jingwei Wang Duanxing Li Huijie Li Jiti Zhou key laboratory of Industrial Ecology and environmental Engineering (ministry of education) School of Environmental Science and TechnologyDalian University of Technology

Indole, a typical nitrogen heterocyclic aromatic pollutant, is extensively spread in industrial wastewater. Microbial degradation has been proven to be a feasible approach to remove indole, whereas the microbial resources are fairly limited. A bacterial strain designated as SHE was isolated and found to be an efficient indole degrader. It was identified as Cupriavidus sp. according to 16 SrRNA gene analysis. Strain SHE could utilize indole as the sole carbon source and almost completely degrade 100 mg/L of indole within 24 hr. It still harbored relatively high indole degradation capacity within p H 4–9 and temperature 25°C–35°C. Experiments also showed that some heavy metals such as Mn2＋, Pb2＋and Co2＋did not pose severe inhibition on indole degradation. Based on high performance liquid chromatography–mass spectrum analysis, isatin was identified as a minor intermediate during the process of indole biodegradation. A major yellow product with m/z 265.0605（C15H8N2O3） was generated and accumulated, suggesting a novel indole conversion pathway existed. Genome analysis of strain SHE indicated that there existed a rich set of oxidoreductases, which might be the key reason for the efficient degradation of indole. The robust degradation ability of strain SHE makes it a promising candidate for the treatment of indole containing wastewater.

关键词： Indole Biodegradation Cupriavidus sp. Metabolic pathway

Selection of microalgae for high CO_2 fixation efficiency and lipid accumulation from ten Chlorella strains using municipal wastewater

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Journal of environmental sciences 2016年第8期28卷 83-91页

作者： Xia Hu Jiti Zhou Guangfei Liu Bing Gui key laboratory of Industrial Ecology and environmental Engineering Ministry of Education School of Environmental Science and TechnologyDalian University of Technology

As significant differences in cellular physiology, metabolic potential and genetics occur among strains with morphological similarity, the screening of appropriate microalgae species for effective CO2 fixation and biodiesel production is extremely critical. In this study, ten strains of Chlorella were cultivated in municipal wastewater influent（MWI） and their tolerance for MWI, CO2 fixation efficiency and lipid productivity were assessed. The results showed that the biomass concentrations of four strains（Chlorella vulgaris, Chlorella64.01, Chlorella regularis var. minima and Chlorella sp.） were significantly higher than other strains. When the cultivation systems were aerated with 10% CO2, Chlorella sp. showed the highest CO2 fixation efficiency（35.51%）, while the highest lipid accumulation（58.48%） was observed with C. vulgaris. Scanning electron microscopy images revealed that the cells of both Chlorella sp. and C. vulgaris kept their normal morphologies after 15 day batch *** findings indicated that Chlorella sp. and C. vulgaris have fairly good tolerance for MWI,and moreover, Chlorella sp. was appropriate for CO2 fixation while C. vulgaris represented the highest potential for producing biodiesel.

关键词： Chlorella strains CO2fixation Lipid accumulation Municipal wastewater influent

Enhanced anaerobic fermentation with azo dye as electron acceptor: Simultaneous acceleration of organics decomposition and azo decolorization

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Journal of environmental sciences 2014年第10期26卷 1970-1976页

作者： Yang Li Yaobin Zhang Xie Quan Jingxin Zhang Shuo Chen Shahzad Afzal key laboratory of Industrial Ecology and environmental Engineering Ministry of Education School of Environmental Science and TechnologyDalian University of Technology

Accumulation of hydrogen during anaerobic processes usually results in low decomposition of volatile organic acids（VFAs）. On the other hand, hydrogen is a good electron donor for dye reduction, which would help the acetogenic conversion in keeping low hydrogen concentration. The main objective of the study was to accelerate VFA composition through using azo dye as electron acceptor. The results indicated that the azo dye serving as an electron acceptor could avoid H2 accumulation and accelerate anaerobic digestion of VFAs. After adding the azo dye, propionate decreased from 2400.0 to 689.5 mg/L and acetate production increased from 180.0 to 519.5 mg/L. It meant that the conversion of propionate into acetate was enhanced. Fluorescence in situ hybridization analysis showed that the abundance of propionate-utilizing acetogens with the presence of azo dye was greater than that in a reference without azo dye. The experiments via using glucose as the substrate further demonstrated that the VFA decomposition and the chemical oxygen demand（COD） removal increased by 319.7 mg/L and 23.3% respectively after adding the azo dye. Therefore, adding moderate azo dye might be a way to recover anaerobic system from deterioration due to the accumulation of H2 or VFAs.

关键词： Azo dye Anaerobic treatment Volatile fatty acids H2accumulation

Enhanced bio-decolorization of1-amino-4-bromoanthraquinone-2-sulfonic acid by Sphingomonas xenophaga with nutrient amendment

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Journal of environmental sciences 2015年第1期27卷 124-130页

作者： Hong Lu Xiaofan Guan Jing Wang Jiti Zhou Haikun Zhang key laboratory of Industrial Ecology and environmental Engineering (ministry of education) School of Environmental Science and TechnologyDalian University of Technology

Bacterial decolorization of anthraquinone dye intermediates is a slow process under aerobic conditions. To speed up the process, in the present study, effects of various nutrients on 1-amino-4-bromoanthraquinone-2-sulfonic acid（ABAS） decolorization by Sphingomonas xenophaga QYY were investigated. The results showed that peptone, yeast extract and casamino acid amendments promoted ABAS bio-decolorization. In particular,the addition of peptone and casamino acids could improve the decolorization activity of strain QYY. Further experiments showed that L-proline had a more significant accelerating effect on ABAS decolorization compared with other amino acids. L-Proline not only supported cell growth, but also significantly increased the decolorization activity of strain QYY. Membrane proteins of strain QYY exhibited ABAS decolorization activities in the presence of L-proline or reduced nicotinamide adenine dinucleotide, while this behavior was not observed in the presence of other amino acids. Moreover, the positive correlation between L-proline concentration and the decolorization activity of membrane proteins was observed, indicating that L-proline plays an important role in ABAS decolorization. The above findings provide us not only a novel insight into bacterial ABAS decolorization, but also an L-proline-supplemented bioaugmentation strategy for enhancing ABAS bio-decolorization.

关键词： 1-Amino-4-bromoanthraquinone- 2-sulfonic acid Sphingomonas xenophaga Enhancement Decolorization Nutrients

Broadband unidirectional acoustic transmission based on piecewise linear acoustic metamaterials

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Chinese science Bulletin 2014年第26期59卷 3239-3245页

作者： Sai Zhang Yu Zhang key laboratory of Underwater Acoustic Communication and marine Information Technology of the ministry of education Xiamen University State key laboratory of marine environmental science Xiamen University

In this paper, a broadband unidirectional acoustic transmission based on inhomogeneous metamaterial shell with radial piecewise linear sound speed distribution is proposed. Acoustic rays in the case of external and internal incidences from the shell are deduced by geometric acoustic theory to show the unidirectional acoustic propagation in the polar coordinate system. Numerical full-wave simulations reveal that one way transmission has the intensity-independent unidirectional transmission feature over a wide frequency range. Finally, a scheme for realization of the proposed one way transmission model is designed and simulated by using multilayered materials, suggesting its potential applications in noise control, acoustic rectifiers,wave absorption and related fields.

关键词：单向传输多层材料线性声学分段线性传声宽带模拟显示声学理论

Response of Microbial Community to Petroleum Stress and Phosphate Dosage in Sediments of Jiaozhou Bay, China

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Journal of Ocean University of China 2014年第2期13卷 249-256页

作者： ZHAO Yangguo CHEN Min BAI Jie LI Xinwei Farhana Zulfiqar WANG Qianli College of environmental science and Engineering Ocean University of China key laboratory of marine Environment and Ecology Ministry of Education

The dynamic microcosms were used to evaluate the effect of oil spills on microbial ecological system in marine sediment and the enhancement of nutrient on the oil removal. The function and structure of microbial community caused by the oil pollution and phosphate dosage were simultaneously monitored by dehydrogenase activity assay and PCR-denaturing gradient gel electrophoresis(DGGE) techniques. The results indicated that the amount of total bacteria in all dynamic microcosms declined rapidly with incubation time. The number of petroleum-degrading bacteria and the activity of sediment dehydrogenase were gradually enhanced by petroleum in the oil-treated microcosms, while they both showed no obvious response to phosphate dosage. In comparison, phosphate spiked heterotrophic bacteria and they showed a significant increase in amount. DGGE profiles indicated that petroleum dosage greatly changed community structure, and the bacteria belonged to class Deltaproteobacteria, and phyla Bacteroidetes and Chlorobi were enriched. This study demonstrated that petroleum input greatly impacted the microbial community structure and consequently the marine sediment petroleum-degrading activity was enhanced. Phosphate dosage would multiply heterotrophic bacteria but not significantly enhance the petroleum degradation.

关键词： marine sediments oil spills dehydrogenase activity phosphate heterotrophic bacteria bacterial community

Characteristics and Influencing Factors of the Microbial Concentration and Activity in Atmospheric Aerosols over the South China Sea

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Journal of Ocean University of China 2021年第2期20卷 257-270页

作者： QI Jianhua YIN Yidan XIE Jiamin LI Mengzhe DING Xue LI Hongtao key laboratory of marine Environment and Ecology Ministry of EducationOcean University of ChinaQingdao 266100China laboratory for marine Ecology and environmental science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China

Oceans are important sources of microbes in atmospheric aerosols;however, information about the characteristics of airborne microbes and their influencing factors over oceans is lacking. Here we report the characteristics of the microbial abundance and activity in aerosols sampled near the sea surface over the South China Sea(SCS) from May to June 2016. The airborne microbial concentration range in the aerosols was 1.68?105 to 4.84?105 cells m-3 over the SCS, reflecting an average decrease of 40% – 54% over the SCS compared with that in the samples from the coastal region of Qingdao. About 63% – 76% of the airborne microbes occurred in coarse particles(> 2.1 ?m), with a variable size distribution over the SCS. The microbial activity range in aerosols, measured by the fluorescein diacetate(FDA) hydrolysis method, was 2.09 – 11.97 ng m-3 h-1 sodium fluorescein(SF) over the SCS, which was 15% – 79% lower than that over the coastal region. These values reflected a different spatial distribution over the SCS from that of the microbial concentration. Except for certain samples, all samples had 68% of the microbial activity occurring in coarse particles. Correlation analysis showed that the microbial abundance and activity were positively correlated with the aerosol, organic carbon(OC), and water-soluble organic carbon(WSOC) concentrations, indicating that the airborne microbes may be related to the reactions of certain water-soluble organic chemicals in the atmosphere. Moreover, the concentrations of airborne microbes were significantly negatively correlated with the horizontal offshore distance. The microbial concentration and activity were significantly correlated with wind speed.

关键词： microbes aerosols microbial activity size distribution WSOC

Spatial distribution and deposition history of nonylphenol and bisphenol A in sediments from the Changjiang River(Yangtze River) Estuary and its adjacent East China Sea

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Acta Oceanologica Sinica 2010年第5期29卷 44-51页

作者： BIAN Haiyan LI Zhengyan LIU Ping PAN Jinfen key laboratory of marine environmental science and Ecology Ministry of Education Qingdao 266100 China College of environmental science and Engineering Ocean University of China Qingdao 266100 China

Nonylphenol（NP） and bisphenol A（BPA） are endocrine disruptors causing harmful effects including feminization and carcinogenesis to various organisms,and consequently,their contamination in natural environment has received wide *** study reports the distribution characteristics of NP and BPA in surface sediments and their deposition history based on a dated sediment core in the Changjiang River（Yangtze River） Estuary and its adjacent East China *** contents of NP and BPA in surface sediments ranged from 1.56-35.8 and 0.72-13.2 ng/g（dry mass）,respectively,with high values recorded in the two mud zones,the Changjiang River Estuarine Mud Zone and the Zhejiang Coastal Mud *** values in the Zhejiang Coastal Mud Zone suggest the possibility of long distance transport of both contaminants through the Changjiang riverine *** contents were not correlated with the distance from the pollution source,indicating other factors including particle deposition rate and sediment grain size obviously affecting the distribution *** was also detected in a sediment core at layers deposited from the year of 1971 to 2001 with contents of up to 20.9 ng/g（dry mass）.The deposition fluxes of NP varied from 0.68 to 17.9 ng/（cm^2 · a） with peaks and valleys reflecting the traces of economic development history in China during the previous three *** was detected at sediment layers deposited from 1973 to 2001 with contents of up to 3.66 ng/*** fluxes of BPA varied from 0.62 to 3.13 ng/（cm^2 · a） showing a similar pattern as *** contents of NP and BPA also indicated potential risks on benthic organisms in the study area.

关键词： nonylphenol bisphenol A endocrine disruptor deposition flux the Changjiang River (Yangtze River) Estuary

Left-handed properties of a composite structure with metallic wires in a homogeneous Lorentz medium

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 159-164页

作者： Yang Bai Fang Xu Li-jie Qiao key laboratory of environmental Fracture(ministry of education) University of Science and Technology BeijingBeijing 100083China

The electromagnetic properties of a composite structure with metallic wires in a Lorentz medium were studied. The results show that the electromagnetic properties of the medium host influence the plasma resonance of metallic wires and the left-handed character of the composite. The plasma frequency of metallic wires reduces with the rise of permittivity or permeability of the medium host. Also, the negative permeability of the medium can destroy the wires’ plasma resonance and prevent the realization of left-handed properties. The high loss of medium permittivity or permeability also inhibits the metallic plasma resonance. The negative influence of the media host on the left-handed properties of the composite structure can be effectively reduced by proper structure design, such as introducing a nonmagnetic medium in the host or using an anisotropic medium.

关键词： electromagnetic waves left-handed materials plasma resonance electromagnetic interaction