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Chen Yin,Fang Dawei,

热带亚热带植物学报 , 1993,
Abstract: The nitrogen-fixing activity of blue-green algae Anabaena 7120 treated by low temperature was markedly declined with increase of NaCl concentration in medium under NaCl stress. When the preincubation of the algae cells was done in dark before experiment for 24 hours or in presence of photosynthetic inhibitors, such as DNP and CCCP, a synergetic great inhibition of nitrogen-fixing activity of Anabaena treated by low temperature under NaCl stress was observed. Nitrogen-fixing activity of Anabaena influenced b...
甘露醇对氯化钠胁迫下蓝藻Anabaena 7120固氮活性的增强效应

Chen Yin,Fang Dawei,

热带亚热带植物学报 , 1996,
Abstract: The NaCl-induced inhibition of nitrogen-fixing activity of blue-green algae Anabaena 7120 was removed to a certain degree by the. introduction of appropriaternannitol into the test system. When the preincubation of algae cells was done in dark before experiment for 24 hours or in the presence of photosynthetic inhibitors, such as DNP or CCCP, the enhancing effect of mannitol on the nitrogen-fixing activity of Anabaena 7120 supressed by NaCl weakened or disappeared. In the addition of O2 together with H2 the enhancing effect of mannitol on nitrogen-fixing activity of Anabaena 7120 was reinforced under NaCl stress. A marked inaction in nitrogen-fixing activity of Anabaena 7120 occurred under NaCl stress when O2 was introduced into the test system alone. When algae cells inactivited by NaCl were incubated in the aerobic condition the accelerated action of mannitol upon the nitrogen-fixing activity was higher than that in anaerobic condition. The mannitol-supported nitrogen-fixing activity of Anabaena 7120 under NaCl stress was accelerated in the addition of N2 together with CO2 or addition of CO2 alone, while it was depressed by adding N2 alone.
Antiviral Lectins from Red and Blue-Green Algae Show Potent In Vitro and In Vivo Activity against Hepatitis C Virus  [PDF]
Yutaka Takebe, Carrie J. Saucedo, Garry Lund, Rie Uenishi, Saiki Hase, Takayo Tsuchiura, Norman Kneteman, Koreen Ramessar, D. Lorne J. Tyrrell, Masayuki Shirakura, Takaji Wakita, James B. McMahon, Barry R. O'Keefe
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0064449
Abstract: Hepatitis C virus (HCV) infection is a significant public health problem with over 170,000,000 chronic carriers and infection rates increasing worldwide. Chronic HCV infection is one of the leading causes of hepatocellular carcinoma which was estimated to result in ~10,000 deaths in the United States in the year 2011. Current treatment options for HCV infection are limited to PEG-ylated interferon alpha (IFN-α), the nucleoside ribavirin and the recently approved HCV protease inhibitors telaprevir and boceprevir. Although showing significantly improved efficacy over the previous therapies, treatment with protease inhibitors has been shown to result in the rapid emergence of drug-resistant virus. Here we report the activity of two proteins, originally isolated from natural product extracts, which demonstrate low or sub-nanomolar in vitro activity against both genotype I and genotype II HCV. These proteins inhibit viral infectivity, binding to the HCV envelope glycoproteins E1 and E2 and block viral entry into human hepatocytes. In addition, we demonstrate that the most potent of these agents, the protein griffithsin, is readily bioavailable after subcutaneous injection and shows significant in vivo efficacy in reducing HCV viral titers in a mouse model system with engrafted human hepatocytes. These results indicate that HCV viral entry inhibitors can be an effective component of anti-HCV therapy and that these proteins should be studied further for their therapeutic potential.
Rice Field Blue-green Algae of Bongaigaon District, Assam  [PDF]
A.K. Das,G.C. Sarma
Our Nature , 2010, DOI: 10.3126/on.v8i1.4344
Abstract: The present study deals with the blue-green algae (BGA) from the rice fields of Bongaigaon district, Assam. 23 species of blue-green algae belongs to 12 genera has been enumerated. Maximum species were found under the genus Nostoc (4), Anabaena (4), which is followed by Scytonema (3) Aphanocapsa (2), Aphanothece (2) and Phormedium (2). Single species was represented by the genera Microcystis , Chroococcus , Merismopedia , Oscillatoria , Aulosira and Calothrix . DOI: 10.3126/on.v8i1.4344
Study the Function of Blue-green Algae in Urban Garbage Compost of Iran  [PDF]
L. Baftehchi,S. Samavat,M. Parsa,N. Soltani
Asian Journal of Plant Sciences , 2007,
Abstract: Blue-green algae as nitrogen fixers have been used in different countries for a long time and are well known as biofertilizer. According to the quality of urban garbage composts of Iran especially in Tehran, diazothrophic cyanobacteria were considered as compost supplier. Cyanobacteria species were collected from paddy fields of north provinces of Iran (Gillan, Mazandaran and Golestan). Fischerella sp. was the dominant species in each province and had the highest content of nitrogen. Different amounts of this cyanobacterium (0.1-1%) and also different ratio of moistures (80-240%) were added to compost. Results showed that using different amounts of algae had no significant effect on growth rate and nitrogen content. Otherwise moisture had significant effect on growth rate of Fischerella sp.
Synthesis of Gold Nanoparticles by Blue-Green Algae Spirulina Platensis  [cached]
Kalabegishvili T.,Faanhof A.,Kirkesali E.,Frontasyeva M.V.
Proceedings of the International Conference Nanomaterials : Applications and Properties , 2012,
Abstract: The synthesis of gold nanoparticles by one of the many popular microorganisms – blue-green algae Spirulina platensis was studied. The complex of optical and analytical methods was applied for investigation of experimental samples after exposure to chloroaurate (HAuCl4) solution at different doses and for different time intervals. To characterize formed gold nanoparticles UV-vis Spectrometry, Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), Energy-dispersive analysis of X-rays (EDAX) were used. It was shown that after 1.5–2 days of exposure the extracellular formation of nanoparticles of spherical form and the distribution peak within the interval of 20-30 nm took place. To determine gold concentrations in the Spirulina platensis biomass neutron activation analysis (NAA) was applied.
Salt Stress Culture of Blue-green Algae Spirulinafusiformis  [PDF]
I.M. Rafiqul,A. Hassan,G. Sulebele,C.A. Orosco
Pakistan Journal of Biological Sciences , 2003,
Abstract: A Study was conducted on the salt stress culture of blue green algae S. fusiformis. The blue green algae S. fusiformis was grown at the different salinity of sea water as 0.2, 0.5, 1.0, 1.2, 1.5, 3.0, 5.0, 7.0, 14.0, 15.0, 16.0, 17.0 and 18.0 ppt which were enriched with Zarouk medium. A new steady state was established after carry out an initial lag phase. The observed growth rate was slower and inversely related with concentration of salt stress i.e. the more was salinity, the slower was growth rate during the experiment. Instead of growth, a decrease in biomass was also observed in high salinity. The specific growth rate at all salt stress culture was lower than that of control (0 ppt). The result showed that the protein and carbohydrate content were varied from 37.3 to 56.1% and 16.8 to 31.4 %, respectively. At 1.0 and 1.2 ppt a marked increase in lipids of 19.6 and 15.6% were observed. Highest carotenoid content of 3.53 mg-1 g dry weight was found at 16 ppt, which is significantly (P<0.05) higher compared to control. Phycocyanin was high at 1 ppt (93 mg 1 g dry weight), which is significantly lower than that of control. The result showed that the production of lipids and carotenes in salt stress culture which would be 1-1.2 ppt and 15-16, ppt respectively in laboratory culture conditions.
Distribution of blue-green algae (Cyanophyta) in streams of Mt. Stara planina: Serbia  [PDF]
Simi? Sne?ana B.
Archives of Biological Sciences , 2002, DOI: 10.2298/abs0204141s
Abstract: Distribution of blue-green algae was studied at 14 sites along five streams in the Stara Planina mountains. Algological samples were taken from the community of benthos and periphyton in the spring (March-May 1991), summer (June-August 1991, August 1996, July 1997), and autumn (September-November 1991, September 1997). Algae of the classes Chamaesiphonophyceae (species of the genus Chamaesiphon) and Hormogoniophyceae (species of the genera Symploca, Phormidium, Oscillatoria, Schizothrix, Nostoc, Rivularia Homoeothrix, Tolypothrix, and Plectonema) were recorded. The species Chamaesiphon cylindricus, Symploca radians, Phormidium coutinhoi, Nostoc coeruleum, Homoeothrix janthina, Plectonema thomasinianum, and Tolypothrix distorta were registered herein first time in Serbia. Occurrence of blue-green algae in highland brooks and rivers of the Stara Planina mountains was monitored in relation to a large number of abiotic factors e.g. altitude above level, stream dimensions (width and depth), substrate bottom type (%), current flow rate, water temperature and pH oxygen concentration, concentrations of nitrates and phosphates, and BOD5, using Principal Coordinates analysis (PCX)).
Effects of Dopant Nano TiO2 on Vegetal Physiology of Blue-green Algae
改性纳米TiO2 对蓝藻的生理生态影响

Lijuan Zhou,Xiaolan Chen,Guobin Deng,Yanyan Wang,Wei Liu,Shanna Chen,

植物学报 , 2008,
Abstract: Synechocystis sp. PCC6803 and Microcystis aeruginosa were treated with the dopant nano TiO2 components 1% Ag,5% Fe2O3, 10% ZnO, and nano TiO2 alone under natural illumination and fluorescent conditions . We determined the content of chlorophyll a, carotenoids, extracellular O2 -. and superoxide dismutase activity in samples. The natural illumination condition was more effective than the fluorescent condition in the photocatalysis of nanometer material. The dopant nano materials were more effective than nano material alone in inhibiting growth of blue-green algae, 1% Ag having the best inhibitory effect. M. aeruginosa has a stronger ability to adapt to superoxide anion stress produced by photocatalysis of nano TiO2 than Synechocystis sp.
Antimicrobial and antioxidant activity of brown algae from the Aegean Sea  [PDF]
Journal of the Serbian Chemical Society , 2009,
Abstract: The present study was conducted to evaluate the antioxidant and antimicrobial activity of methanol, dichloromethane and hexane extracts, as well as the essential oils of brown algae (Phaeophyta) Colpomenia sinuosa, Dictyota dichotoma, Dictyota dichotoma var. implexa, Petalonia fascia and Scytosiphon lomentaria. The essential oil of the macroalgae was obtained by steam distillation and analyzed by GC and GC/MS. The antioxidant activity of the algal extracts was determined using the procedures of inhibition of b-carotene bleaching and ABTS+ methods. The antioxidant effects of the extracts were compared with those of commercial antioxidants, such as butylated hydroxytoluene (BHT), butylated hydroxyanisol (BHA) and a-tocopherol. The hexane extracts of D. dichofoma var. implexa had a higher phenolic content than the other extracts. The dichloromethane extract of S. lomentaria was found to be more active in the decolorization of ABTS+ than the other extracts and generally the dichloromethane extracts were more active than the methanol and hexane extracts. Antimicrobial activities of the extracts were assessed against Gram (+) and Gram (–) bacteria and one yeast strain by the disk diffusion method. According to the re sults, the dichloromethane extracts generally showed more potent antimicro bial activity than the methanol and hexane extracts at concentrations 1.5 and 1.0 mg/disk.
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