Photosynthetic pigments in soils from northern Victoria Land (continental Antarctica) as proxies for soil algal community structure and function

Although soil algae are among the main primary producers in most terrestrial ecosystems of continental Antarctica, there are very few quantitative studies on their relative proportion in the main algal groups and on how their distribution is affected by biotic and abiotic factors. Such knowledge is essential for understanding the functioning of Antarctic terrestrial ecosystems. We therefore analyzed biological soil crusts from northern Victoria Land to determine their pH, electrical conductivity (EC), water content (W), total and organic C (TC and TOC) and total N (TN) contents, and the presence and abundance of photosynthetic pigments. In particular, the latter were tested as proxies for biomass and coarse-resolution community structure. Soil samples were collected from five sites with known soil algal communities and the distribution of pigments was shown to reflect differences in the relative proportions of Chlorophyta, Cyanophyta and Bacillariophyta in these sites. Multivariate and univariate models strongly indicated that almost all soil variables (EC, W, TOC and TN) were important environmental correlates of pigment distribution. However, a significant amount of variation is independent of these soil variables and may be ascribed to local variability such as changes in microclimate at varying spatial and temporal scales. There are at least five possible sources of local variation: pigment preservation, temporal variations in water availability, temporal and spatial interactions among environmental and biological components, the local-scale patchiness of organism distribution, and biotic interactions.     

水生藻类的环境指示作用

为了方便有效地监测水环境中有氮磷污染物、重金属、农药及其他有机污染物等,笔者研究了水生藻类对水体环境中相应污染物的敏感性和耐受性,以及污染物对水域生态系统中藻类种群结构所造成的影响,分析了污染物对水生藻类的毒理和富集等,获得了大量数据。结果表明,水生藻类对一些水环境污染物具有较好的指示作用,该方法便于直观快速地调查分析相应水体的污染情况。     

卡特兰水培技术研究

为研究名贵兰花的水培技术,促进水培兰花的生产与消费,以兰科卡特兰为试材,从卡特兰水生根系诱导,营养液培养,筛选出水培卡特兰诱导根系的最适宜的NAA浓度和营养液配方,在培养的过程中,防治根腐烂和水藻的生成。结果表明,低浓度NAA（5mg/L）对诱导水生根系具有促进作用;KC营养液是水培卡特兰较好的营养液;加强根部通气有利于防止卡特兰根系的腐烂,在培养过程中添加2～3滴含氯霉素的滴眼液有助于防止藻类的生长。     

鲢鳙鱼和藻类治理关系的初步研究

2008年7月至9月在蠡湖设置宝界桥和石塘桥两个实验点进行鲢鳙鱼和藻类治理关系的初步研究,采用常规生物学方法,测定了鲢鳙鱼的体长、体重、消化腺指数、肠长指数、食物充塞度、肥胖度系数、饱满度等参数。实验表明微囊藻和颤藻在鲢鳙鱼体内得不到完全消化,但可以破坏藻类的存在形式,一定程度上也说明鲢鳙鱼对于微囊藻和颤藻的治理有一定的作用。     

淡水浮游藻类在池塘养殖中的负面影响

淡水浮游藻类是鱼类和其他经济动物的直接或间接的饵料基础,是水域原始生产者,在决定水域生产性能上有重要意义。但是近几年的深入研究表明,淡水浮游藻类在池塘养殖中也存在着一些负面影响。     

Algal Lectins as Potential HIV Microbicide Candidates

The development and use of topical microbicides potentially offers an additional strategy to reduce the spread of the Human Immunodeficiency Virus (HIV). Carbohydrate-binding agents (CBAs) that show specificity for high mannose carbohydrates on the surface of the heavily glycosylated envelope of HIV are endowed with potent anti-HIV activity. In fact, a number of algal lectins such as cyanovirin-N, microvirin, microcystis viridis lectin, scytovirin, Oscillatoria agardhii agglutinin and griffithsin are considered as potential microbicide candidates to prevent the sexual transmission of HIV through topical applications. They not only inhibit infection of cells by cell-free virus but they can also efficiently prevent virus transmission from virus-infected cells to uninfected CD4(+) target T-lymphocytes and DC-SIGN-directed capture of HIV-1 and transmission to CD4(+) T lymphocytes. This review focuses on the structural properties and carbohydrate specificity of these algal lectins, their antiviral activity against HIV and several other enveloped viruses, their safety profile and viral resistance patterns.     

Evaluation of Antioxidant Activity of Marine Algae-Extracts From Korea

Among 51 marine algae distributed along the Korean coast, Sargassum muticum (Yendo) Fensholt, Ishige okamurae Yendo, Ecklonia cava Kjellman, Polysiphonia morrowii Harvey, Dictyopteris undulata Holmes, Sargassm micracanthum (Kutzing) Endlicher, and Sargassum macrocarpum C. Agarch were found to have potent antioxidant activity. Additionally, the reducing power of marine algae-extracts was consistent with diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity. Because little is known about Sargassum muticum (Yendo) Fensholt, Ishige okamurae Yendo, Ecklonia cava Kjellman, Polysiphonia morrowii Harvey, Dictyopteris undulata Holmes, Sargassm micracanthum (Kutzing) Endlicher, and Sargassum macrocarpum C. Agarch, these marine algae may act as candidates for potent antioxidant food materials and are expected to have functional activity for foods and pharmaceuticals for treating oxidative diseases.     

Single nucleotide polymorphisms found in the red alga Furcellaria lumbricalis (Gigartinales): new markers for population and conservation genetic analyses

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