双液相系统中疏水化合物的微生物降解

双液相系统是由水相与不互溶非水相组成的多相系统,在微生物降解疏水化合物时,双液 相系统有助于克服污染物可生物利用性障碍,提高污染物的生物降解速率。文中介绍了双液相 系统促进微生物降解的机制,微生物吸收底物的方式,以及底物与有机溶剂双重抑制作用存在时 微生物的生长模型等方面的研究进展。

Variation of Phosphorus Bioavailability in the Re-suspended Sediments

The variation of phosphorus （P） bioavailability in terms of water soluble P （WSP ）, readily desorbable P （RDP）, algal available P （AAP）, and NaHCo3 extracting P （Olsen-P） in the re-suspended sediments was investigated in laboratory experiments, in which the waters and sediments were taken from campus canal. The results indicate that sediment re-suspension can promote the migration, of soluble reactive P （SRP） from overlying water to sediments. The contents of AAP and Olsen-P in re-suspended sediments reduced obviously, whereas the values of the sediments in the control increased slightly, compared with the initial state, indicating that the P bioavailability in the sediments could be rcduced evidently due to sediment re-suspension. The content and characteristics of iron-bound P （BD-P） significantly affect the formation of AAP. The formation of OlservP has close relationship with the contents of BD-P, almninium-botmd P （AI-P）, and organic P （NaOH-nrP）.

Isolation and Properties Characterization of Biosurfactant Synthesized by Pyrene Degrading Bacillus subtilis C19

Bacillus subtilis strain C19, capable of ulilizing pyrene as a sole of carbon and energy, was isolated from marine Indonesian Archipelago. In biodegradation of pyrene by B. subtilis C19, various metabolites was isolated and identified by chromatographic and spectral analyses. Lipopeptide biosurfactant was produced and it has stable emulsification activity. Biosurfactant was produced for enhancing pyrene uptake and bioavaibility. After 30 days incubation, there were no toxic metabolite and biodegradation of pyrene was already complete （only 0.02% undegradable metabolite）. Therefore, this strain is suitable for PAHs （polyaromatic hydrocarbons） contaminated environment recovery.

From Conservation to Sustainable Development-A Case Study of Angkor World Heritage Site, Cambodia

The World Heritage Committee of UNESCO has called for a strategic commitment from its States Parties to strengthen links between heritage conservation and sustainable development. Fulfilment of this commitment will require integration of the conservation of sites with the sustainable use and management of natural resources in a larger area beyond the boundaries of sites. Identification and demarcation of areas for conserving World Heritage sites and sustainable development of broader regions must derive from an in-depth knowledge of people-environment relationships. The management of Angkor-an iconic World Heritage site -has been primarily focused on conservation and restoration of monuments within the boundaries of the site. However, that focus is now shifting towards addressing environmental, social and economic challenges for sustainable development of the broader landscape described in this paper as the Angkor ecosystem. Angkor has the potential to demonstrate the application of an ecosystem approach to sustainable development--advocated under the UN Convention on Biological Diversity. The site could be a laboratory for new research on cultural ecosystem services as a tool for bridging site conservation to the sustainable development of the Siem Reap province where the site is located.

Success of native and invasive plant congeners depends on inorganic nitrogen compositions and levels

Aims Successful plant invaders usually exhibit three strategies:Jack-of-all-trades(more robust in stressful sites),Master-of-some(more responsive in favorable sites)and Jack-and-master(both robustness and responsiveness).To revisit these strategies,we examined how soil inorganic nitrogen(N)compositions and levels influence the success of native and invasive plant congeners in the context of plant communities.Methods We conducted an experiment involving three fixed factors:species origin,N composition and N level.Here,we selected 21 plant species(eight pairs of invasive and native congeners and five non-congeneric natives)to assemble plant communities,which were subject to nine N environments consisting of three N compositions(3:1,2:2 and 1:3 NO3−/NH4+)and three N levels(low,medium and high N).We determined the following metrics:total biomass,relative biomass(a proxy of species success),mortality rate and mortality time.Important Findings Across nine N environments,native and invasive congeners exhibited similar total biomass,relative biomass and mortality time,but invaders had a marginally lower mortality rate than natives.Similar success between native and invasive congeners was linked to their similar growth and tolerance.N compositions influenced mortality time and N levels affected the total biomass and relative biomass.Importantly,species origin,N composition and N level interactively affected the total biomass,relative biomass and mortality time.These findings suggest that native and invasive plant congeners may be similarly successful across different N environments,and that inorganic N compositions and levels both contribute to plant invasion success.

Tea and human health: biomedical functions of tea active components and current issues

Originating in China, tea and tea planting have spread throughout the world since the middle of the Tang dynasty. Now people from 160 countries in the world are accustomed to tea drinking. A brief history of tea＇s medicinal role in China and its spread to the world are introduced. The effectiveness of tea active components and tea drinking on major human diseases, including cancer, metabolic syndrome, cardiovascular disease, and neurodegenerative diseases, is discussed. Also presented are some related issues, such as the bioavailability of tea active components, the new formulations of tea polyphenols, and the safety for consumers of dietary supplements containing tea polyphenols.