广东省鼎湖山钼矿区亚气生蓝藻的反射光谱特性

亚气生蓝藻（Ｃｙａｎｏｐｈｙｃｅａｅ）的反射光谱,在反射红外谱区（７７０—１０００ ｎｍ ）缺少绿色种子植物的高反射平台峰,反射率曲线平缓． 在矿体含钼量不同的矿化土壤上生长的亚气生蓝藻和矿区外缘正常土壤上生长的亚气生蓝藻,不但其细胞富集钼与矿化土壤的含钼量呈正相关关系,而且,亚气生蓝藻反射率与蓝藻细胞含钼量也呈正相关关系．在反射红外区矿化土壤上生长的钼矿蓝藻反射率明显地较矿区外缘正常土壤上生长的蓝藻高１３％ —２７％     

失活蓝藻的趋光性

将固氮鱼腥藻置于０．５ｍｏｌＫ３ＰＯ４,７％甲醛或３６－３８％甲醛,７０％或９５％乙醇,冰醋酸,或将藻丝悬浮液煮沸或经１５磅１５分高温高压处理之后,藻丝立即变色失活,但仍能向光照方向移动和聚集,此种能力保持１－２周。在１ｍｏｌＮａＯＨ或ＨＣｌ溶液中,此种能力丧失。失活的东湖项圈藻,钝顶螺旋藻和组囊藻也有趋光性。     

Growth response of Anacystis nidulans to sodium and phosphate availability

The growth response of Anacystis nidulans to sodium and phosphate was studied in batch culture under controlled laboratory conditions. Sodium (range=0–10 mg/l) significantly enhanced growth, most notably, after sodium and phosphate starvation. The magnitude of the increase in growth was dependent on the initial cell density, external concentrations of phosphate, sodium, and potassium, and the nutritional status of the algal inoculum. The increase in ambient sodium levels in many lakes may provide a competitive advantage to some blue-green algae.     

柄杆菌对固氮蓝藻生物量及色素的影响

柄杆菌对固氮蓝藻生物量和色素的影响研究结果表明:多态柄杆菌(Caulobacter polymorphus)017-41或新月柄杆菌(Caulobacter creseentus)CB_2的活菌、死菌及破碎细胞悬液分别与鱼腥藻(Anabaena)、念珠藻(Nostoc)不同藻珠混合培养时,试验组生长量均优于对照组;对衰老黄化的藻培养物的生长刺激作用尤为显著;试验组藻培养物的藻蓝或藻红素含量亦明显高于对照组。其作用机理尚待进一步阐明。     

Alteration of the gastrointestinal microbiota of mice by edible blue-green algae

Aims:  To characterize the effect of edible blue-green algae (cyanobacteria) on the gastrointestinal microbiota of mice.
Methods and Results:  C57BL/6J mice were fed a diet supplemented with 0% or 5% dried Nostoc commune , Spirulina platensis or Afanizominon flos-aquae (w/w) for 4 weeks. Molecular fingerprinting of the colonic microbiota using denaturing gradient gel electrophoresis revealed that administration of N. commune induced major alterations in colonic microbiota composition, while administration of S. platensis or A. flos-aquae had a more subtle impact. Community profile analysis revealed that administration of N. commune did not reduce microbial diversity indices of the colonic microbiota. Despite its pronounced effects on the bacterial composition in the colon, total bacterial numbers in the gut of mice fed N. commune were not reduced as assessed by quantitative real-time PCR and bacteriological culture.
Conclusions:  The results presented here show that administration of blue-green algae, and especially N. commune , alters colonic microbiota composition in mice with limited effects on total bacterial numbers or microbial diversity.
Significance and Impact of the Study:  Blue-green algae are consumed in many countries as a source of nutrients and to promote health, and they are intensively studied for their pharmaceutical value. Given the importance of the gut microbiota for many host functions, the effects of blue-green algae on gut microbial ecology revealed during this study should be considered when using them as food supplements or when studying their pharmaceutical properties.     

Alloxan: A growth accelerator for a nitrogen-fixing blue-green alga

Effect of Alloxan was studied on a nitrogen-fixing blue-green alga: Westiellopsis prolifica in pure cultures. Concentrations of Alloxan, 10 g to 50 g/ml stimulate the growth of the alga and increase the chlorophyll, carotin and phycocyanin content of the cultures.     

Comparison of the long-wave chlorophyll fluorescence in various green and blue-green algae and diatoms

Two types of long-wave fluorescence bands with similar band shape occur at room temperature in various algae: F_II700 and F_I715. F_II700 occurs in a limited number of algae, follows PS II transients, increases with culture age and is moderately increased by cooling to 83 K. F_I715 occurs in most algae, especially Anabaena, but much less in most diatoms and Tribonema. It does not follow PS II transients, does not increase with culture age and is much increased by cooling to 83 K.An interpretation for the characteristics of F_II700 and F_I715 is given.     

STRONG PROBABILITY OF LETHAL TOXICITY IN THE BLUE-GREEN ALGA MICROCYSTIS VIRIDIS LEMMERMANN1

Lethal toxicity (intraperitoneal, mouse) was examined in relation to Species composition of samples containing bloom-forming Microcystis populations from natural waters and correlated with toxicity of laboratory strains of four Microcystis formas and species. Toxicity was not always associated with the presence of M. aeruginosa f . aeruginosa Elenkin. A sample with almost all cells of M. aeruginosa f . aeruginosa showed no toxicity, However samples comprised of a high percentage of M. viridis Lemmermann often showed lethal toxicity. Toxicity tests were done on culture strains M. aeruginosa f aeruginosa, M. aeruginosa f flos-aquae Elenkin , M. viridis and M. wesenbergii Kamárek. All five cultured strains of M. viridis were found to be toxic, while only one out of nine strains of M. aeruginosa f . aeruginosa was toxic. Six strains of M. wesenbergii showed no toxicity, It is recommended that attention should be paid to the occurrences and possibility of toxic bloom of M. viridis from the standpoint of water management and public health .     

固氮蓝藻培养和应用的结果与展望

固氮蓝藻是一类低等原核植物。它能进行固氮作用,固定空气中分子态氮成为氮素化合物;又能进行光合作用,将二氧化碳变为碳素化合物并放出氧气,为自身的固氮提供能源和还原剂。由于具有以上功能,它们适应性很强往往是贫瘠土壤的先驱植物,因此,很早就引起了人们的重视。     

On the algal ecology of the lowland Iraqi marshes

An account is given of the algal vegetation in the near boat channels in the central area of the lowland Iraqi marshes. Sampling was carried out in February and September. The water here may be characterized as relatively turbid, slightly saline, highly calcareous and probably typically mesotrophic. Diatoms dominated the phytoplankton, many of the species being ones which are at least as characteristic of benthic communities. Periphyton was more conspicuous in February than September, with filamentous green algae especially common in February. Blue-green algae were more common in September; they frequently formed a felt with several different species and irregular deposition of calcite. Heterocystous blue-green algae were frequent in the periphyton but apparently not so in the plankton. A well-developed laminated community of blue-green algae and purple phototrophic bacteria occurred on the wooden hull of a boat.     

Valyl tRNA's of Anacystis nidulans

Anacystis nidulans was found to contain three tRNA^val isoacceptors which could be charged also in heterologous systems with aminoacyl synth     

The role of modelling in the control of toxic blue-green algae

Blooms and scums of blue-green algae (cyanobacteria)have occurred throughout the world for many years andare only one of many problems associated withover-enrichment by nutrients of fresh and marinewaters. Although much studied and written about,eutrophication poses complex and difficult managementproblems. The role of modelling as an aid to thecontrol of blue green algae is discussed.     

The algal periodicity in Tjeukemeer during 1968–1978

The seasonal periodicity of algal numbers and biomass and of chlorophyll-a was investigated in the shallow, eutrophic, alkaline and peaty lake, Tjeukemeer, The Netherlands, during 1968–1978. Diatoms and Scenedesmus spp. were abundant throughout the whole period.Several blue-green algal species, occurring since 1971, usually dominated for most of the year. Relative abundance of algal species in Tjeukemeer during the study period were compared with that in 1955–1960.     

4. Geographic distribution of freshwater blue-green algae

The analysis of the currently available data for morphologically unambiguously defined freshwater blue-green algae indicates that besides (sub-)cosmopolitan species, taxa with a more restricted distribution also exist. Many of these have a holarctic or pantropic distribution. It is hypothesized that, besides the distribution of ecological niches, temperature is one of the main controlling factors restricting species to particular latitudinal zones. Furthermore, the presence of species with a regional distribution (endemics) can not be ruled out, indicating that other factors must be considered. The possible role of dispersal capacities and of dispersal rates in relation to the earth history and to the speciation of blue-green algae is discussed.     

A greenhouse study on the effect of inoculation of N-fixing blue-green algae in an alluvial soil treated with P and Mo on the yield of rice and changes in the N-content of soil

Summary The efficiency of the inoculation of three cultures of N-fixing blue-green algaeviz. (i)Aulosira fertilissima (A₁), (ii)Nostoc muscorum (A₂) and (iii) their mixture (A₃) in increasing the grain and straw yield of rice, nitrogen uptake in grain and nitrogen content in soil was studied in a green house experiment with an alluvial soil in presence or absence of urea nitrogen application. Inoculation significantly increased the grain and straw yield of rice and nitrogen uptake in grain, but the efficiency of inoculation gradually decreased with the increase in the levels of urea nitrogen application, the extent of decrease varying with the algal cultures inoculated. The nitrogen content in the soils after the crop harvest recorded a significant increase due to inoculation but after air drying the soil a marker decrease of the same was observed, which indicated that most of the nitrogen added to the soil by blue-green algae through fixation did not persist after air drying the soil.     

柴达木盆地荒漠土壤蓝藻群落的初步研究

本文分析了柴达木盆地东部和中部具有代表性地区的丘陵、戈壁和沙丘的蓝藻种类组成、生物量及主要的土壤化学成分;采用了模糊聚类、系统聚类及多元线性回归等方法分析藻类的群落及其与环境因子的关系。共鉴定出21种蓝藻,其中6种为国内首次报道。研究表明:土壤含磷量、总盐量及与粘性和湿度有关的土壤结构是决定柴达木盆地蓝藻群落组成的重要因素。     

Sediment-to-water blue-green algal recruitment in response to alum and environmental factors

The sediment-to-water recruitment of blue-green algae was investigated in a shallow lake following treatment with aluminum sulfate and sodium aluminate to control sediment phosphorus (P) release. A comparison of results from two summers each before and after treatment indicates that the treatment did not universally impact the recruitment of either sporulating or non-sporulating forms of blue-green algae. Blooms of Anabaena, Aphanizomenon, and Coelosphaerium resulted predominantly from growth in the water column following strong recruitment episodes lasting up to two weeks, while Microcystis populations were relatively insensitive to periodically high inputs from recruitment. The development of planktonic populations of Gloeotrichia echinulata, by contrast, were largely dependent on sustained recruitment in response to adequate light and temperature regimes at the sediment surface.The cellular P content of recruited G. echinulata colonies was unaffected by the accumulation of aluminum floc to the lake sediments. Both G. echinulata and C. naegelianum showed elevated levels of cellular P in newly recruited colonies as compared to planktonic colonies, indicating P transport from the sediments to the water column. Total P translocation by blue-green algae was negligible in the absence of a substantial recruitment of G. echinulata. The recruitment of G. echinulata, and hence the magnitude of P translocation, was therefore more responsive to environmental conditions prevalent at the sediments than to direct effects of the treatment itself.     

FUNCTIONAL PHYCOBILISOMES FROM TOLYPOTHRIX TENUIS (CYANOPHYTA) GROWN HETEROTROPHICALLY IN THE DARK1

Phycobiliproteins produced in dark-grown cells of Tolypothrix tenuis Kützing formed Phycobilisomes functionally capable of energy transfer. The phycobilisomes could be recovered in high yield (80% of extracted phycobiliproteins). Phycobilisomes from cells grown without light and in red light had the same size, morphology, and spectral characteristics. They had a phycocyanin to allophycocyanin malar ratio of 3:1. Phycocyanin and allophycocyanin in phycobilisomes were energetically coupled as indicated by their fluorescence emission (maximum of ca. 690 nm at –196° C) and excitation spectra. Phycobilisomes were attached to the outer surface of thylakoids and were hemidiscoidal in shape. In thin sections they had a diameter of 42 ± 3nm, a height of 24 ± 4 nm and a thickness of 10 ± 2 nm. Isolated and negatively stained Phycobilisomes were larger with a diameter of 51 ± 2 nm and height of 33 ± 2 nm, Isolated phycobilisomes in face view had a central core of three units and six peripheral rods. Each rod appeared to be composed of three hexamers (three double discs), consistent with the observed dimensions and substructure. After Phycoerythria synthesis was induced by a 15 min green light exposure, phycobilisomes of dark-grown cells exhibited energy transfer from phycoerythrin to a long wavelength allophycocyanin, indicating that phycoerythrin synthesized in darkness was incorporated into functional phycobilisomes.