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Effects of culture conditions on ligninolytic enzymes and protease production by Phanerochaete chrysosporium in air

Journal of environmental Sciences 2008年第1期20卷 94-100页

作者： XIONG Xiaoping WEN Xianghua BAI Yanan QIAN Yi State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental Science and Engineering Tsinghua University Beifing 100084 China.

The production of ligninolytic enzymes and protease by Phanerochaete chrysosporium was investigated under different culture conditions. Different amounts of medium were employed in free and immobilized culture, together with two kinds of medium with different C/N ratios. Little lignin peroxidase （LIP）（〈 2 U/L） was detected in free culture with nitrogen-limited medium （C/N ratio： 56/2.2, in mmol/L）, while manganese peroxidase （MnP） maximum activity was 231 and 240 U/L in 50 and 100 ml medium culture, respectively. Immobilized culture with 50 ml nitrogen-limited medium gave the highest MnP and LiP production with the maximum values of 410 and 721 U/L separately on the day 5; however, flasks containing 100 ml nitrogen-limited medium only produced less MnP with a peak value of 290 U/L. Comparatively, carbon-limited medium （C/N ratio： 28/44, in mmol/L） was adopted in culture but produced little MnP and LiE Medium type had the greatest impact on protease production. Large amount of protease was produced due to glucose limitation. Culture type and medium volume influence protease activity corporately by affecting oxygen supply. The results implied shallow immobilized culture was a possible way to gain high production of ligninolytic enzymes.

关键词： protease culture conditions ligninolytic enzymes Phanerochaete chrysosporiurn

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Ecosystem health assessment of urban rivers and lakes-Case study of “the six lakes”in Beijing,China

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Frontiers of environmental Science & Engineering 2008年第2期2卷 209-217页

作者： Fengling ZHANG Jingling LIU Zhifeng YANG Yongli LI State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China

The assessment of the ecosystem health of urban rivers and lakes is the scientific basis for their management and ecological *** study developed a three-level indicator system for its *** results indicated that:Zhonghai and Nanhai are in the state of transition from unhealthy to critical state and all the other lakes are in unhealthy *** environmental quality,structure and function of the aquatic ecosystem,and the structure of waterfront areas were the *** was ranked as poor and the others were all ranked as very ***,the ecological environment of Zhonghai and Nanhai were better than the others,the sums of the degree of membership to the healthy state and critical state were all close to *** the restorations of these lakes were *** sums of the degree of membership to the healthy state and critical state of the other lakes were under 0.3,as it was difficult to restore these *** suggestions on scientific management and ecological restoration of the six lakes were proposed:①To control non-point pollution and to improve the water quality of six lakes and the water entering into these lakes;②To improve the hydrological conditions of six lakes;③To rehabilitate the aquatic ecosystem and waterfront areas.

关键词： urban rivers and lakes ecosystem health assessment indicator system the six lakes

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Response of reed community to the environment gradientwater depth in the Yellow River Delta, China

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Frontiers in Biology 2008年第2期3卷 194-202页

作者： Baoshan CUI Xinsheng ZHAO Zhifeng YANG Bin CHEN Na TANG Xuejie TAN State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China

We investigated and monitored a reed community in the *** on the bio-ecological characteristics and β-diversity of reed communities in different environmental gradients(mainly based on water depth)of the Yellow River Delta were collected through multianalysis,extremum analysis and β-diversity index *** accordance with the square sum of deviations(Ward)cluster analysis,10 sampling plots were divided into six types with the dominant plants in different plots varying according to the change in environmental *** dominant plants in these plots varied from aquatic plants to xerophytes and salt tolerant plants as water depth *** average height and diameter of the reeds at breast level were significantly correlated with the average water *** fitness curves of average density and coverage with average water depth were *** the average water depth was 0.3 m,the average density and coverage of reeds reached the apex value,while the height and diameter of the reeds at breast level increased with the water *** were obvious changes to the environmental gradient in the Yellow River *** transitional communities were also found to exist in the Yellow River Delta by β-diversity *** species appeared with the change in water *** occurrence of substitute species is determined by the function of common species between adjacent *** different functions of common species led to differences in community structure and function and differences in dominant *** result reflects the variations of species present in different habitats and directly reflects environmental *** values of β-diversity indices of adjacent plots were higher than those of nonadjacent *** are transition zones between the xerophytes and aquatic plants in the Yellow River *** an aquatic environment,the similarity of reed community is higher than that of xeromorphic *** β-diversity index can refl

关键词： reed β-diversity environmental gradient wetland the Yellow River Delta

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Reactivity of ambient volatile organic compounds(VOCs) in summer of 2004 in Beijing

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Chinese Chemical Letters 2008年第5期19卷 573-576页

作者： Shan Huang Min Shao Sihua Lu Ying Liu State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China

Ambient volatile organic compounds （VOCs） were sampled at six sites in Beijing in the summer of 2004 and analyzed by GCMS. The chemical reactivities of 73 quantified VOCs species were evaluated by OH loss rates （LOH） and ozone formation potentials （OFPs）. Top 15 reactive species, mainly alkenes and aromatics, were identified by these two methods, and accounted for more than 70% of total reactivity of VOCs. In urban areas, isoprene was the most reactive species in term of OH loss rate, contributing 11.4% to the LOH of VOCs. While toluene, accounting for 9.4% of OFPs, appeared to have a long-time role in the photochemical processes. Tongzhou site is obviously influenced by local chemical industry, but the other five sites showed typical urban features influenced mainly by vehicular emissions.

关键词： VOC Reactivity OH loss rate Ozone formation potential

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Vertical characteristics of the Hani terrace paddyfield ecosystem in Yunnan,China

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Frontiers in Biology 2008年第3期3卷 351-359页

作者： Baoshan CUI Zheyuan YOU Min YAO School of Environment Beijing Normal UniversityBeijing 100875China State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875China

The Hani terrace paddyfield in Yunnan Province,China is categorized as a‘constructed wetland’under the Lamsar Convention *** Hani terrace paddyfield ranges from an altitude of 144 to 2000 m above sea level(ASL)in the southern slopes of the Ailao Mountains,angling down at a range of 15°to 75°.In this study,we investigated the ecosystem of the terrace paddyfields in the Mengpin and Quanfuzhuang administrative villages located at the center of the cultural heritage conservation district in the Hani terrace *** Hani terrace paddyfield ecosystem structure is"forest-village-terrace paddyfield-river"in the order of descending *** and water samples were sequen-tially taken from forests,villages and the terrace paddy-fields to be able to study the vertical characteristics of Hani’s terrace ***_(4)-P and NH_(3)-N in water were measured to test for water *** soil nutrient factors were tested,including organic material(OM),char and nitrogen ratio(C/N),pH,total nitrogen(TN),total phosphorus(TP),available phosphorus(AP),and available potassium(AK).Soil quality was also eval-uated using the characteristics of the soil nutrient *** changes in the landscape,wetland types,wetland plants,hydrology and soil nutrients were *** showed that:(1)Hani’s terrace paddyfield can be divided into five types of wetlands;the rice varieties and cultivation patterns vary in each type of wetland.(2)Hani’s terrace paddyfield has a great capacity for water conservation and a strong ability to purify *** impoundage of Hani’s terrace paddyfield is about 5050 m^(3)/hm^(2).Contaminants in the terrace paddyfield soils decrease exponentially with the decline in altitude.(3)Comparison of soil quality in five different land use types indicates decreasing soil quality from forest to terrace land to terrace paddyfield to water *** for headwater soil,single factors such as OM,TN and TP,and the comp

关键词： Hani’s terrace paddyfield wetland landscape wetland types wetland water wetland soil vertical characteristics

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Temporal-spatial variation and the influence factors of precipitation in Sichuan Province,China

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Frontiers in Biology 2008年第2期3卷 236-240页

作者： Ruimin LIU Zhenyao SHEN State Key Laboratory of Environment Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China

Precipitation is a key factor in the water *** the same time,precipitation is the focus of study in meteorology and climatology,ecological environmental assessment,non-point source pollution and so *** the temporal-spatial variation and the corresponding factors of precipitation has become the object of hydrology and *** on the annual precipitation data,we analyzed the spatial distribution of precipitation in Sichuan Province in China as well as the temporal-spatial variation and the corresponding influence factors *** results show that the amount of precipitation was abundant,but the spatial distribution was not consistent with it and the amount of precipitation gradually declined from the south-east to the north-west in Sichuan Province,***,the spatial distribution was different throughout the *** result of correlation analysis indicated that elevation,temperature and air pressure were three key factors affecting the amount and distribution of precipitation,and the correlation coefficients were 20.56,0.38 and 0.45 ***,the relationship between the slope of topography and precipitation were significantly negative and the average correlation coefficient was 20.28.

关键词： Sichuan Province precipitation geostatistics temporal-spatial variation

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Modelling the carrying capacity of urban ecosystem

Modelling the carrying capacity of urban ecosystem

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2nd International Conference on Bioinformatics and Biomedical Engineering, iCBBE 2008

作者： Xu, Linyu Yang, Zhifeng Li, Wei State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing China

ISBN: (纸本)9781424417483

The urban ecosystem is a Social-Economic-Natural Complex consisting of human beings and their surrounding. Because resources and environmental quality are crucial to the existence and development of an urban ecosystem, the development of an urban ecosystem is necessarily built on the basis of interactions among environmental carrying capacity (ECC), resource carrying capacity (RCC) and social-economic development capacity (SEDC). A single component's capacity should not be studied without considering the integrity of the whole system. In this paper, the concept of 'Compound carrying capacity' (CCC) is introduced and studied as an index of the interactions among ECC, RCC and SEDC, as a basis for meeting the challenges of urban sustainable development and eco-city building. Using this index, it is discussed in both theory fundamentals and quantitative models how these three kinds of capacity function to sustain the urban ecosystem. The concept of CCC is introduced to improve the comprehensive understanding of this system's structure and functions. Compared with traditional concepts, the CCC of the urban ecosystem includes the ability to develop and thus is characterized by being more dynamic. This dynamism shows in the ability of cities to respond when put under pressure. Clearly, this dynamic is not endless, both environmental, resource and social-economic development capacities have limits. A comparative study of urban ecosystems and the human immune systems shows that both systems have similar features. Thus, the CCC model is discussed in this paper in light of the biology immunity theory. In this it is assumed that the urban ecosystem is the material input and its main function is to offer eco-services. The extent of these services is dependent on both the intrinsic carrying capacity and the acquired carrying capacity of the urban ecosystem. The methodology for both calculation and adjustment mechanism of the CCC is outlined, with reference to the urban ecosystem

关键词： Sustainable development

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Isolation of a Pseudomonas Stutzeri strain that degrades 1,2,4-trichlorobenzene and characterization of its degradative plasmid

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Frontiers of environmental Science & Engineering 2008年第1期2卷 69-72页

作者： Lei SONG Hui WANG Hanchang SHI Hongying HU Environmental Simulation and Pollution Control State Key Joint Laboratory Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

The genetic information encoding metabolic pathways for xenobiotic compounds in bacteria often resides on catabolic *** aim of the present work was to know the location of the genes for degrading 1,2,*** this paper a 1,2,4-trichlorobenzene-degrading strain THSL-1 was isolated from the soil of Tianjin Chemical Plant using 1,2,4-trichlorobenzene as the sole carbon *** strain was identified as Pseudomonas stutzeri through morphologic survey and 16S rDNA sequence determination.A plasmid was discovered from strain THSL-1 by using the alkali lysis *** the plasmid was transformed into ***109 by the CaCl2 method,the transformant could grow using 1,2,4-trichlorobenzene as the sole carbon source and had the degradation function of 1,2,***,it could be deemed that the plasmid carried the degradative genes of 1,2,*** average size of the plasmid was finally determined to be 40.2 Kb using selectively three kinds of restricted inscribed enzymes(HindIII,BamHI,and XholI)for single cutting and double cutting the plasmid pTHSL-1,respectively.

关键词： 1,2,4-trichlorobenzene 16S rDNA degradative plasmid Pseudomonas sp.

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Improvement of detection method of Cryptosporidium and Giardia in reclaimed water

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Frontiers of environmental Science & Engineering 2008年第3期2卷 380-384页

作者： Tong ZHANG Xing XIE Hongying HU Yudong SONG Qianyuan WU Zusheng ZONG Environmental Simulation and Pollution Control State Key Joint Laboratory Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Cryptosporidium and Giardia are two typical species of pathogenic protozoans that seriously endanger water *** works indicated that detection of Cryptosporidium and Giardia with modified United states environmental Protection Agency(USEPA)method-1623 using a membrane filtration-elution for sample concentration attained better recovery and lower cost compared to the USEPA *** improvements of membrane filtration-elution step as well as immunomagnetic separation(IMS)steps were investigated and an optimized method for detection of Cryptosporidium and Giardia in wastewater reclamation system was recommended in this *** experimental results show that an overnight soak of the membrane after scraping and vortex agitation before elution could enhance and stabilize the *** turbidity to 4 NTU by adding kaolin clay before filtration could effectively improve the recovery of low-turbidity *** the concentrate after centrifugation and twice acid dissociation both reduced the impact of water quality to protozoan *** in different water samples were determined by this optimized method,and the recovery of Cryptosporidium and Giardia were above 70% and 80%respectively,much higher than the acceptance of method-1623.

关键词： concentration Cryptosporidium Giardia immunomagnetic separation(IMS) wastewater reuse

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Turnover and loss of nitrogenous compounds during composting of food wastes

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Frontiers of environmental Science & Engineering 2008年第2期2卷 251-256页

作者： Yanmei YANG Xiangfeng ZHANG Zhifeng YANG Beidou XI Hongliang LIU College of River and Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentBeijing Normal UniversityBeijing 100875China Chinese Research Academy of Environmental Sciences Beijing 100012China

Few people have so far explored into the research of the dynamics of various nitrogenous compounds(including water-soluble nitrogen)in composting of food *** study aimed to investigate the solid-phase nitrogen,water-soluble nitrogen,nitrogen loss together with ammonia volatilization in the process of food wastes composting.A laboratory scale static aerobic reactor in the experiment was employed in the composting process of a synthetic food waste,in which sawdust was used as the litter *** the experiment,oxygen was supplied by continuous forced ventilation for 15 *** results have shown that the concentrations of total nitrogen and organic nitrogen decrease significantly in the composting process,whereasNH_(4)^(+)-N concentration increases together with little fluctuation in NO_(3)^(-)-*** composting,the total content of the water-soluble nitrogen compounds in the compost greatly increased,the total nitrogen loss amounted to 50% of the initial nitrogen,mainly attributed to ammonia volatilization.56.7% of the total ammonia volatilization occurred in the middle and late composting of the thermophilic *** suggested that the control at the middle and late composting of thermophilic stage is the key to nitrogen loss in the food waste compost.

关键词： composting nitrogen transformation nitrogen loss ammonia volatilization

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