| phycobilisomes from the blue-green algae aphanizomenon flos-aquae and anabaena variabilis. | phycobilisomes (pbs) were isolated from aphanizomenon flos-aquae and anabaena variabilis. the absorption spectra and second derivative of the absorption spectra of isolated pbs indicate the presence of phycoerythrocyanin, and allophycocyanin. the fluorescence spectra of pbs were measured at room temperature and -196 degrees c. undamaged pbs have the principal fluorescence maximum in the region of 660 nm at room temperature and in the region of 685-690 nm at -196 degrees. when the pbs were heated ... | 1979 | 121545 |
| isolation and structures of microcystins from a cyanobacterial water bloom (finland). | a hepatotoxic cyanobacterial (blue-green algal) water bloom was collected from a constructed water reservoir in finland. the water bloom contained two cyanobacterial species, microcystis aeruginosa and aphanizomenon flos-aquae. two hepatotoxins, 1 and 2, were isolated from extracts of lyophilized cells. the structures of 1 and 2 were assigned based upon their amino acid analyses on a waters pico tag hplc system and a chiral gc capillary column (chirasil val iii), fast atom bombardment mass spect ... | 1992 | 1485342 |
| [production of the antibiotic-algicide cyanobacterin lu-2 by a filamentous cyanobacterium nostoc sp]. | a strain of cyanobacterium of nostoc has been isolated, and found to produce a new antibiotic cyanobacterin lu-2. the antibiotic is synthesized by the cyanobnacterium under intensive cultivation conditions in a liquid mineral medium. cyanobacterin lu-2 is an exometabolite; its maximum accumulation in the medium is achieved at 34 degrees. cyanobacterin lu-2 is active against many cyanobacteria tested, including those of microcystis and aphanizomenon which are principals to give rise to blooms in ... | 1991 | 1819038 |
| occurrence of the hepatotoxic cyanobacterium nodularia spumigena in the baltic sea and structure of the toxin. | water blooms formed by potentially toxic species of cyanobacteria are a common phenomenon in the baltic sea in late summer. twenty-five cyanobacterial bloom samples were collected from open and coastal waters of the baltic sea during 1985 to 1987, and their toxicity was determined by mouse bioassay. all of 5 bloom samples from the southern baltic sea, 6 of 6 from the open northern baltic sea (gulf of finland), and 7 of 14 finnish coastal samples were found to contain hepatotoxic cyanobacteria. n ... | 1989 | 2506812 |
| [interaction of phycocyanin and chlorophyll in aphanizomenon flos-aque cells]. | | 1974 | 4218856 |
| toxins of a blue-green alga: similarity to saxitoxin. | toxins were isolated from the freshwater blue-green alga aphanizomenon flos-aquae. the toxic fractions were characterized by paper and thin-layer chromatography, isolation characteristics, infrared spectra, physiological activity, and reactivity with specific color reagents. the toxic fractions appear to be similar, if not identical, to saxitoxin (paralytic shellfish toxin), which is produced by the marine dinoflagellate gonyaulax catenella. | 1968 | 5684499 |
| demonstration of a toxin from aphanizomenon flos-aquae (l.) ralfs. | | 1968 | 5724889 |
| toxicity and environmental requirements of a strain of aphanizomenon flos-aquae (l.) ralfs. | | 1969 | 5764275 |
| some aspects of the ecophysiology of cyanobacteria. | fresh waters rich in nutrients often show mass development of cyanobacteria. the kind of cyanobacteria to be found depends on the properties of the lake. in non-stratified shallow lakes, the most common species oscillatoria agardhii. in stratified lakes, cyanobacteria can be found in restricted zones of the deeper part of the lakes, and always possess cells with very active gas vacuoles. the most common species are microcystis aeruginosa, oscillatoria agardhii var isothrix, oscillatoria "var red ... | 1983 | 6416128 |
| comparison of the toxins of the blue-green alga aphanizomenon flos-aquae with the gonyaulax toxins. | a toxic strain of aphanizomenon flos-aquae (nh-1), isolated from a toxic bloom in a pond in durham, new hampshire, has been mass cultured in the laboratory. the toxin was extracted by ultrasonic disruption of the cells and purified by; (a) filtration through a 10 kilodalton filter, and (b) chromatography on a strong cation exchange resin column using 0.01 m, then 0.1 m, ph 5, sodium acetate buffer followed by 0.75 m hydrochloric acid. mouse assays and fluorescence generated by hydrogen peroxide ... | 1982 | 6814018 |
| [identification of volatile metabolites produced by blue-green algae, oscillatoria splendida, o. amoena, o. geminata and aphanizomenon sp]. | | 1981 | 6820045 |
| the distribution of the outer gas vesicle protein, gvpc, on the anabaena gas vesicle, and its ratio to gvpa. | previous studies have shown that gas vesicles isolated from the cyanobacterium anabaena flos-aquae contain two types of protein, gvpa, a small hydrophobic protein that forms the main ribbed structure, and gvpc, a protein comprising five repeats of a 33-amino-acid-residue motif, which is located on the outer surface of the gvpa shell. gvpc was shown to increase the critical collapse pressure of the gas vesicles; it was thought to do this by forming a series of molecular ties that bind the ribs to ... | 1993 | 8254305 |
| antibacterial properties of extracts from selected planktonic freshwater cyanobacteria--a comparative study of bacterial bioassays. | aqueous and methanol extracts from five selected cyanobacteria were examined for antibacterial properties in six different bacterial bioassays. all five cyanobacteria revealed antibacterial properties. methanol extracts made from tychonema bourrellyi, aphanizomenon flos-aquae and cylindrospermopsis raciborskii showed the most pronounced inhibitory effects, aqueous extracts made from microcystis aeruginosa and t. bourrellyi possessed evident antibacterial properties. the bacterial bioassays were ... | 1998 | 9717298 |
| risk assessment of microcystin in dietary aphanizomenon flos-aquae. | aphanizomenon flos-aquae, a cyanobacterium that is marketed as a health food supplement, is harvested from natural blooms in klamath lake (oregon) that are occasionally contaminated by microcystis spp. regulatory agencies in several countries are developing regulations to control the amount of microcystin in drinking water and other products, including products produced from a. flos-aquae. regulation of microcystin (mc), a toxin produced by microcystis spp. that is potentially present in natural ... | 1999 | 10499991 |
| 7-epicylindrospermopsin, a toxic minor metabolite of the cyanobacterium aphanizomenon ovalisporum from lake kinneret, israel. | a toxic minor metabolite, 7-epicylindrospermopsin (1), was isolated from a culture of the cyanobacterium aphanizomenon ovalisporum isolated from lake kinneret in israel. homonuclear and inverse-heteronuclear 2d nmr techniques, as well as hrms and comparison of the nmr data with model compounds, enabled the structure determination of the new compound. four polymethoxy-1-alkenes, 3-6, were isolated from the lipophilic extract of the cyanobacterium as well. | 2000 | 10757726 |
| assessing potential health risks from microcystin toxins in blue-green algae dietary supplements. | the presence of blue-green algae (bga) toxins in surface waters used for drinking water sources and recreation is receiving increasing attention around the world as a public health concern. however, potential risks from exposure to these toxins in contaminated health food products that contain bga have been largely ignored. bga products are commonly consumed in the united states, canada, and europe for their putative beneficial effects, including increased energy and elevated mood. many of these ... | 2000 | 10811570 |
| new anabaenopeptins, potent carboxypeptidase-a inhibitors from the cyanobacterium aphanizomenon flos-aquae. | anabaenopeptins i (1) and j (2), two new ureido bond-containing cyclic peptides, were isolated from the cultured cyanobacterium aphanizomenon flos-aquae (nies-81) as potent carboxypeptidase-a (cpa) inhibitors. the gross structures of 1 and 2 were established by spectroscopic analysis, including the 2d nmr techniques. the absolute configurations of 1 and 2 were determined by spectral and chemical methods. anabaenopeptins i and j inhibited cpa with ic(50) values of 5.2 and 7.6 ng/ml, respectively. | 2000 | 11000037 |
| site-specific restriction endonucleases in cyanobacteria. | planktic cyanobacteria were screened for endodeoxyribonucleases. principal component analysis (pca) was employed to demonstrate a potential relationship between certain enzymes and a group of cyanobacteria. the data were obtained from a data bank and this study. | 2000 | 11123471 |
| sodium channels blocked by aphantoxin obtained from the blue-green alga, aphanizomenon flos-aquae. | | 1982 | 6281943 |
| vitamin b 12 production and depletion in a naturally occurring eutrophic lake. | the distribution of vitamin b(12) within upper klamath lake was surveyed at approximately monthly intervals during a period from september 1968 to november 1969. high concentrations (up to 1.8 mug/g of dry sediment) characteristically occurred at the water-sediment interface, with a sharp decline below this area. a heavy bloom of aphanizomenon flos-aquae occurred from the latter part of may through october 1969. b(12) concentrations of the uppermost sediments, from all but one sampling site, inc ... | 1972 | 4622828 |
| purification of aphanizomenon flos-aquae toxin and its chemical and physiological properties. | | 1973 | 4199124 |
| vertical distribution of potentially pathogenic free-living amoebae in freshwater lakes. | the vertical distribution of thermotolerant (37 degrees c and 45 degrees c) free-living amoebae (fla) in warm monomictic lakes was determined in relation to the onset of thermal stratification and associated physical and chemical changes. the position of abiotic or biotic particulate layers in the water column was located by using a submersible horizontal beam transmissometer that measures attenuance, or the absorption and scattering of light by particulates in the water column. during mixis, th ... | 1985 | 3989753 |
| molecular characterization of planktic cyanobacteria of anabaena, aphanizomenon, microcystis and planktothrix genera. | toxic and non-toxic cyanobacterial strains from anabaena, aphanizomenon, calothrix, cylindrospermum, nostoc, microcystis, planktothrix (oscillatoria agardhii), oscillatoria and synechococcus genera were examined by rflp of pcr-amplified 16s rrna genes and 16s rrna gene sequencing. with both methods, high 16s rrna gene similarity was found among planktic, anatoxin-a-producing anabaena and non-toxic aphanizomenon, microcystin-producing and non-toxic microcystis, and microcystin-producing and non-t ... | 2001 | 11321098 |
| long-chain alkanediols: biological markers for cyanobacterial contributions to sediments. | one significant family of sedimentary lipids of widespread occurrence are series of c28-c32 alkanediols and hydroxyketones. the recognition of the same series of alkanediols as major lipid components of a field population of the cyanobacterium aphanizomenon flos-aquae leads us to propose that these lipids are markers for cyanobacterial inputs to sediments. the frequency of occurrence of the alkanediols in sedimentary environments supports the recent finding that cyanobacteria are major contribut ... | 1988 | 3131613 |
| comparison of liquid chromatography/mass spectrometry, elisa, and phosphatase assay for the determination of microcystins in blue-green algae products. | more than 100 samples of blue-green algae products (consisting of aphanizomenon, spirulina, and unidentified blue-green algae) in the form of pills, capsules, and powders were collected from retail outlets from across canada. the samples were extracted with 75% methanol in water and centrifuged to remove solids. aliquots of the extracts along with spiked blank sample extracts were sent to each participating laboratory and independently analyzed for microcystins by enzyme-linked immunosorbent ass ... | 2001 | 11501902 |
| paralytic shellfish poisons produced by the freshwater cyanobacterium aphanizomenon flos-aquae nh-5. | a single filament clonal isolate of aphanizomenon flos-aquae was made from a water bloom sample taken at a small pond near durham, new hampshire, in 1980. when batch cultured the strain was toxic to mice and had an i.p. ld50 of about 5.0 mg/kg. using an extraction procedure originally designed for paralytic shellfish poisons and other neurotoxins of freshwater cyanobacteria, a purification method was developed. the procedure involved acidified water/ethanol extraction of the cells followed by ul ... | 1986 | 3085292 |
| paralytic shellfish toxins in bivalves which are not associated with dinoflagellates. | paralytic shellfish toxins (psp toxins) were detected in the freshwater bivalve corbicula sandai collected from lake biwa, shiga prefecture, japan, and marine mussel septifer virgatus from mutsu bay where known causative dinoflagellates and their cysts have never been observed. the toxin profile of c. sandai and s. virgatus was considerably different from suspected causative organisms aphanizomenon flos-aquae and protogonyaulax spp., respectively. the causative organism(s) responsible for psp to ... | 1989 | 2617541 |
| [investigations of the immunomodulatory effect of cyanobacterial extracts]. | resulting from the knowledge that cyanobacteria (blue-green algae) are able to produce pharmacologically active substances the aqueous extracts from several cyanobacteria species and strains (microcystis aeruginosa, synechocystis aquatilis, oscillatoria redekei, anabaena flos-aque, aphanizomenon flos-aquae, oscillatoria rubescens, oscillatoria tenuis) were tested for their immunomodulating activity. extracts from oscillatoria redekei 051, oscillatoria tenuis 01 and synechocystis aquatilis 428 ca ... | 1991 | 1801597 |
| microalgae as food and supplement. | the microalgae chlorella spp., dunaliella spp., and scenedesmus spp., and the cyanobacteria spirulina spp., and aphanizomenon flos-aquae, are being used as nutrient-dense foods and sources of fine chemicals. they have significant amounts of lipid, protein, chlorophyll, carotenoids, vitamins, minerals, and unique pigments. they may also have potent probiotic compounds that enhance health. their historical and current use are reviewed in this article. | 1991 | 1741951 |
| a zoogloea sp. associated with blooms of anabaena flos-aquae. | bacteria were found attached to the heterocysts of aphanizomenon flos-aquae and embedded within the mucilage of both anabaena flos-aquae and microcystis aeruginosa in freshwater plankton. electron microscopy of thin sections preceding the peak of an anabaena flos-aquae bloom showed that the density of bacterial cells was 7.4 x 10(5) cells/ml in the planktonic macroenvironment and 2.6 x 10(11) cells/ml within the microenvironment of cyanobacterial mucilage. the bacteria occurred in aggregates and ... | 1978 | 99218 |
| psp toxins from aphanizomenon flos-aquae (cyanobacteria) collected in the crestuma-lever reservoir (douro river, northern portugal). | the presence of paralytic shellfish poisoning (psp) toxins in cultures of aphanizomenon flos-aquae, isolated from the crestuma-lever reservoir, was found by reversed phase high performance liquid chromatography employing two isocratic elution systems for the separation of psp toxins. with the first isocratic elution protocol, the presence of apolar toxins as saxitoxin, decarbamoyl saxitoxin and neosaxitoxin not detected. on the other hand, gtx4, gtx1 and gtx3 as well as cs toxins were present ei ... | 2001 | 11137533 |
| paralytic shellfish toxins in the freshwater cyanobacterium aphanizomenon flos-aquae, isolated from montargil reservoir, portugal. | montargil reservoir, located in a dry flat area in the centre of portugal, was filled in 1958 to fulfil agricultural, electric and industrial requirements. in may 1996, an intensive bloom of phytoplankton was detected. the algal community was strongly dominated by cyanobacteria with predominance of aphanizomenon flos-aquae from may to june and microcystis aeruginosa from july to august. extracts of samples collected during the bloom period showed high toxicity by mouse bioassay. during the m. ae ... | 2000 | 10858510 |
| toxicity in a water column following the stratification of a cyanobacterial population development in a calm lake. | cyanobacteria, including the genera anabaena, aphanizomenon, microcystis, and oscillatoria, are known to release or have the potential to release phycotoxins into the water. indeed, there are documented cases of both animal and human intoxication. data obtained from field observations and laboratory experiments demonstrate a correlation between the development of the cyanobacterial population and the level of phycotoxin present in the water, though it should be noted that not all cyanobacterial ... | 1999 | 10335601 |
| cellular fatty acids as chemotaxonomic markers of the genera anabaena, aphanizomenon, microcystis, nostoc and planktothrix (cyanobacteria). | the cellular fatty acid content of 22 cyanobacterial strains belonging to the genera anabaena, aphanizomenon, calothrix, cylindrospermum, nostoc, microcystis and planktothrix were analysed. the identities of the major peaks were confirmed by ms. correspondence analysis of the data revealed three distinct groups formed by the microcystis strains, the nostoc/planktothrix strains and the anabaena/aphanizomenon/cylindrospermum strains. the calothrix strain did not cluster with the other heterocystou ... | 2002 | 12054217 |
| insect (locusta migratoria migratorioides) test monitoring the toxicity of cyanobacteria. | an insect test was developed to investigate the toxicity of cyanobacteria. the african locust, locusta migratoria migratorioides r.f. was used as a test animal instead of mouse. the cyanobacteria tested were aphanizomenon flos-aque, anabaena aphanizomenoides, cylindrospermopsis raciborskii, microcystis aeruginosa. the toxicity of authentic microcystin-lr was also tested. cyanobacteria producing toxins killed the animals when the homogenized cell suspension was injected into the animals. the locu ... | 1998 | 9745918 |
| mueggelone, a novel inhibitor of fish development from the fresh water cyanobacterium aphanizomenon flos-aquae. | a novel c18 lipid, containing a 10-membered lactone, mueggelone (1), was isolated from a field-collected sample of aphanizomenon flos-aquae, together with the known compound lupenyl acetate (3). both structures were secured using extensive spectroscopic analysis (1d and 2d nmr, ms, ir). biological activity assessment of both compounds indicated them to have significant inhibitory effects on fish embryo larval development. | 1997 | 9428164 |
| characterization of cyanobacteria by sds-page of whole-cell proteins and pcr/rflp of the 16s rrna gene. | planktonic, filamentous cyanobacterial strains from different genera, both toxic and nontoxic strains, were characterized by sds-page of whole-cell proteins and pcr/rflp of the 16s rrna gene. total protein pattern analysis revealed the mutual relationships at the genus level. restriction fragment length polymorphism (rflp) of the 16s rrna gene with reference strains proved to be a good method for the cyanobacterial taxonomy. the nonheterocystous strains outgrouped from the nitrogen-fixing ones. ... | 1997 | 9382701 |
| diversity of aphanizomenon flos-aquae (cyanobacterium) populations along a baltic sea salinity gradient. | colony-forming cyanobacteria of the genus aphanizomenon form massive blooms in the brackish water of the baltic sea during the warmest summer months. there have been recent suggestions claiming that the baltic sea aphanizomenon species may be different from aphanizomenon flos-aquae found in lakes. in this study, we examined variability in the morphology and 16s-23s rrna internal transcribed spacer (its) sequences of a. flos-aquae populations along a salinity gradient from a string of lakes to a ... | 2002 | 12406717 |
| strain characterization and classification of oxyphotobacteria in clone cultures on the basis of 16s rrna sequences from the variable regions v6, v7, and v8. | a major problem in development of a polyphasic taxonomy is that the identification of oxyphotobacterial strains (cyanobacteria and prochlorophytes) in culture collections may be incorrect. we have therefore developed a diagnostic system using the dna sequence polymorphism in the 16s rrna regions v6 to v8 for individual strain characterization and identification. pcr primers amplifying v6 to v8 from oxyphotobacteria in unialgal cultures were constructed. direct solid-phase or cyclic sequencing wa ... | 1997 | 9212409 |
| microcystins in slovene freshwaters (central europe)--first report. | cyanobacterial blooms are frequent in the north-eastern region of slovenia, where the agricultural activities are intensive, resulting in higher water eutrophication. in a two year monitoring program we identified eighteen blooms of cyanobacteria, fifteen being hepatotoxic by intraperitoneal mouse bioassay. the approximate ld100 varied from 50-1000 mg/kg (dry cell weight/animal weight) and gross pathological signs were characteristic of cyanobacterial hepatotoxins. frequently the blooms were dom ... | 1997 | 9131592 |
| analysis by gas chromatography-mass spectrometry of the fatty acid composition during temperature adaptation in aphanizomenon flos-aquae, a diazotrophic cyanobacterium from the baltic sea. | | 1996 | 8879019 |
| isolation and purification procedures for the preparation of paralytic shellfish poisoning toxin standards. | paralytic shellfish poisoning (psp) is caused by mixtures of saxitoxin analogs of which more than eighteen are known. reliable and sensitive analytical methods and assays for these toxins are essential to protect the consumer and the shellfish industry, but research has been restricted by a shortage of the pure compounds. only saxitoxin has so far been generally available as a psp toxin standard, yet sulfated analogs usually occur in higher concentrations than saxitoxin in toxic marine algae and ... | 1994 | 7952941 |
| freshwater phytoplankton quantification by chlorophyll a: a comparative study of in vitro, in vivo and in situ methods. | standard iso method for chlorophyll a quantification (extraction into ethanol, spectrophotometrical quantification at 665 and 750 nm), spectrofluorometry (reader for 96 wells, excitation 410 nm, emission 670 nm), and a submersible fluorescence probe for in situ phytoplankton quantification (excitation 410, 525, 570, 590, and 610 nm, emission 685 nm) were compared in different freshwater environments-reservoirs and rivers. the iso method is accepted as a standard method but requires sample handli ... | 2004 | 14723919 |
| viability changes in human neutrophils and monocytes following exposure to toxin extracted from aphanizomenon flos-aquae. | an in vitro method for detecting toxin produced by aphanizomenon flos-aquae is described. this procedure is more sensitive than the mouse toxicity test and is based on viability changes in human leukocytes. | 1980 | 6773647 |
| species variation in kinetic properties of ribulose 1,5-bisphosphate carboxylase/oxygenase. | several kinetic parameters of ribulose-1,5-bisphosphate (rubp) carboxylase/oxygenase from different species were measured and compared. the co2/o2 specificity (vcko/vokc) was found to be about 80 in the enzymes from several c3 species and two c4 species. specificity values of 58 and 70, respectively, were found in enzymes from the c4 plants setaria italica and sorghum bicolor. two enzymes from cyanobacteria had values of about 50. substitution of mn2+ for mg2+ reduced the co2/o2 specificity by a ... | 1983 | 6582802 |
| instability and variable toxicity of hbp-tx, a toxin in the cyanobacterium microcystis aeruginosa. | it was found that autoxidative degradation is responsible for the inactivation of the unstable microcystis toxin hbp-tx. the purified toxin was similar in its properties to the "fast-death-factor" in microcystis, described as a cyclic peptide in the literature. the apparent presence of an entirely different toxin was simulated by the partially inactivated hbp-tx. a number of associated fluorescent compounds were identified as the non-toxic degradation products of the toxin. as a consequence, as ... | 1984 | 6426092 |
| structure and heme environment of ferrocytochrome c553 from 1h nmr studies. | cytochrome c553 is a photosynthetic electron transport protein found in algae and cyanobacteria. we have purified cytochromes c553 from five cyanobacteria and studied the structures of the ferrocytochromes by 1h nmr spectroscopy at 360 and 470 mhz. using standard nmr techniques and by comparing the amino acid sequences of four cytochromes c553 with their 1h nmr spectra, we have assigned in the spectrum of the aphanizomenon flos-aquae protein 18 resonances to specific amino acid residues and 12 r ... | 1982 | 6286617 |
| the amino acid sequence of low-potential cytochrome c550 from the cyanobacterium microcystis aeruginosa. | the low-potential cytochrome c550 has been purified from the cyanobacterium microcystis aeruginosa and its amino acid sequence has been determined. the protein contains 135 amino acid residues with the cys-x-x-cys-his heme binding site at residues 37 to 41. the sequence from residue 28 to 45 shows similarity to cytochrome c553 residues 1 to 18 when the heme binding sites are aligned. another region of similarity is in the carboxyl-terminal regions of these two proteins. the two aligning regions ... | 1989 | 2539046 |
| warmer winters: are planktonic algal populations in sweden's largest lakes affected? | winters in sweden have become warmer in the 1990s, and as a consequence the timing of ice break-up and the growth and decline of spring phytoplankton has shifted, starting earlier. even spring temperatures have become warmer, leading to an earlier beginning of the summer phytoplankton growth. the spring-ward shift in phytoplankton population growth has resulted in an extension of the growing season by at least one month. although mean total phytoplankton biomass from may to october has not incre ... | 2001 | 11878032 |
| development of a universal microarray based on the ligation detection reaction and 16s rrna gene polymorphism to target diversity of cyanobacteria. | the cyanobacteria are photosynthetic prokaryotes of significant ecological and biotechnological interest, since they strongly contribute to primary production and are a rich source of bioactive compounds. in eutrophic fresh and brackish waters, their mass occurrences (water blooms) are often toxic and constitute a high potential risk for human health. therefore, rapid and reliable identification of cyanobacterial species in complex environmental samples is important. here we describe the develop ... | 2004 | 15574913 |
| phylogenetic and morphological evaluation of the genera anabaena, aphanizomenon, trichormus and nostoc (nostocales, cyanobacteria). | the heterocytous cyanobacteria form a monophyletic group according to 16s rrna gene sequence data. within this group, phylogenetic and morphological studies have shown that genera such as anabaena and aphanizomenon are intermixed. moreover, the phylogeny of the genus trichormus, which was recently separated from anabaena, has not been investigated. the aim was to study the taxonomy of the genera anabaena, aphanizomenon, nostoc and trichormus belonging to the family nostocaceae (subsection iv.i) ... | 2005 | 15653847 |
| a novel gene encoding amidinotransferase in the cylindrospermopsin producing cyanobacterium aphanizomenon ovalisporum. | the hepatotoxin cylindrospermopsin is produced by several cyanobacteria species, which may flourish in tropical and sub-tropical lakes. biosynthesis of cylindrospermopsin is poorly understood but its chemical nature, and feeding experiments with stable isotopes, suggested that guanidinoacetic acid is the starter unit and indicated involvement of a polyketide synthase. we have identified a gene encoding an amidinotransferase from the cylindrospermopsin producing cyanobacterium aphanizomenon ovali ... | 2002 | 12007659 |
| toxic cyanobacteria and microcystin concentrations in a public water supply reservoir in the brazilian amazonia region. | toxic cyanobacteria in public water supply reservoirs represent a serious health risk as they can release potent cyanotoxins into the water. in the present study we analyzed surface water collected from the utinga reservoir, the main source of drinking water for the city of belem-pa, in order to characterize the reservoir's cyanobacterial biota and to determine the toxicity of these organisms and the concentration of microcystins in raw and treated water. the cyanobacterial biota included potent ... | 2005 | 15904685 |
| seasonal variation of microcystin concentrations in the saint-caprais reservoir (france) and their removal in a small full-scale treatment plant. | at the saint-caprais reservoir (france), a mono-specific bloom of aphanizomenon flos-aquae occurs every year in the autumn months. levels of microcystin-lr (mcyst-lr) in this reservoir were evaluated by protein phosphatase type 2a (pp2a) inhibition test as mcyst-lr equivalents in both raw and drinking water. analysis by hplc of the crude extract of the mono-specific bloom of a. flos-aquae revealed the presence of mcyst-lr with a low concentration of 270.3 +/- 20.4 ng/g wet weight. mcyst-lr equiv ... | 2002 | 12146878 |
| phylogenetic comparison of the cyanobacterial genera anabaena and aphanizomenon. | morphological analysis and sequencing of the 165 rrna gene, the spacer region of the ribosomal operon (its1) and the rbclx (rubisco) region was performed on 26 anabaena strains and 14 aphanizomenon strains isolated from several lakes in denmark, finland and france. based on their morphology, anabaena strains differed from strains of aphanizomenon: the vegetative cells, heterocysts and akinetes were significantly wider in anabaena than in aphanizomenon. phylogenetic trees based on the 16s rdna, i ... | 2002 | 12361299 |
| purification and characterization of phycocyanin from the blue-green alga aphanizomenon flos-aquae. | aphanizomenon flos-aquae (afa) is a blue-green alga and represents a nutrient-dense food source. in this study the presence of phycocyanin (pc), a blue protein belonging to the photosynthetic apparatus, has been demonstrated in afa. an efficient method for its separation has been set up: pc can be purified by a simple single step chromatographic run using a hydroxyapatite column (ratio a620/a280 of 4.78), allowing its usage for health-enhancing properties while eliminating other aspecific algal ... | 2006 | 16266834 |
| dicarboxylic and fatty acid compositions of cyanobacteria of the genus aphanizomenon. | the occurrence of dioic, hydroxy, branched, and unsaturated fatty acids in cyanobacteria of the genus aphanizomenon growing in different freshwater lakes has been studied. unusual dicarboxylic (from 4.52 to 7.14%) and other fatty acids were identified by gas chromatography/mass spectrometry (gc/ms). | 2001 | 11240396 |
| uracil moiety is required for toxicity of the cyanobacterial hepatotoxin cylindrospermopsin. | a new natural derivative of the sulfated guanidinium zwitterionic toxin cylindrospermopsin, 7-epi-cylindrospermopsin, was recently isolated from the cyanobacterium aphanizomenon ovalisporum (forti). the toxicity of the molecule (ld50 ip 5 d), estimated by mouse bioassay, was 200 microg/kg mouse, a value similar to that of cylindrospermopsin. treatment of cylindrospermopsin with chlorine solution or chlorine-related oxidants produced two new derivatives. the chemical structure of these products w ... | 2001 | 11245397 |
| effects of toxic and non-toxic cyanobacteria on grazing, zooplanktivory and survival of the mysid shrimp mysis mixta. | we measured the effect of toxic and non-toxic cyanobacteria strains on grazing, predation rates and survival of the mysid shrimp mysis mixta by means of laboratory experiments. juvenile and adult m. mixta fed most actively on the non-toxic strains aphanizomenon flos-aquae and nodularia sphaerocarpa as on high quality food, the green flagellate brachiomonas submarina, whereas grazing on the toxic n. spumigena was significantly lower than on the other strains. the mysids showed normal functional r ... | 2001 | 11245880 |
| radioreceptor assays for sensitive detection and quantitation of saxitoxin and its analogues from strains of the freshwater cyanobacterium, anabaena circinalis. | toxic freshwater cyanobacteria can contaminate water supplies and adversely effect humans, agricultural livestock, and wildlife. toxicity is strain-specific so morphological observations alone cannot predict the hazard level. two microtiter plate based bioassays have emerged for measuring saxitoxin (stx) and its derivatives, commonly found in the freshwater cyanobacteria anabaena and aphanizomenon. they use radioactively labeled stx binding by sodium channels, stx's pharmacological target, or an ... | 2001 | 11348083 |
| the history of cyanobacterial blooms in the baltic sea. | long-term information on possible changes in cyanobacterial blooms in the baltic sea, formed mainly by nodularia spumigena and aphanizomenon sp., was sought in published records in historical (years 1887-1938) and modern (years 1974-1998) phytoplankton data sets. old and new sampling methods and fixatives were tested to improve the comparison of data that had been collected and analyzed in different ways. a hundred years ago, plankton was mainly of interest as a source of fish food; eutrophicati ... | 2001 | 11697246 |
| dynamics of the volatile organic substances associated with cyanobacteria and algae in a eutrophic shallow lake. | the volatile substances present in a eutrophic shallow lake were determined qualitatively and quantitatively during the growing season, allowing a first-time analysis of the dynamics of these compounds in a water body. the major compounds found were beta-cyclocitral, alpha-cyclocitral, beta-ionone, 1,3,3-trimethylcyclohexene, 2,2,6-trimethylcyclohexanone, 2,6,6-trimethylcyclohex-2-en-1-one, eucalyptol, geosmin, two argosmin isomers, pent-1-en-3-ol, pent-1-en-3-one, heptadec-1-ene, heptadec-cis 5 ... | 1984 | 16346520 |
| evidence for bacterial chemotaxis to cyanobacteria from a radioassay technique. | lyngbya birgei and aphanizomenon flos-aquae elicited a significant chemotactic attraction of aeromonas hydrophila compared with controls lacking cyanobacteria. there was a positive exponential relationship between biomass (chlorophyll a) of l. birgei and a. flos-aquae and chemotactic attraction of a. hydrophila. the assay equipment was simple and reliable and could be used to study bacterial chemotaxis in other species in situ. | 1991 | 16348544 |
| isolation of three high molecular weight polysaccharide preparations with potent immunostimulatory activity from spirulina platensis, aphanizomenon flos-aquae and chlorella pyrenoidosa. | this research describes the identification of three new high molecular weight polysaccharide preparations isolated from food-grade microalgae that are potent activators of human monocytes/macrophages: "immulina" from spirulina platensis, "immunon" from aphanizomenon flos-aquae, and "immurella" from chlorella pyrenoidosa. these polysaccharides are structurally complex and have estimated molecular weights above ten million daltons. all three polysaccharides are highly water soluble and comprise be ... | 2001 | 11731916 |
| allergenic (sensitization, skin and eye irritation) effects of freshwater cyanobacteria--experimental evidence. | many studies have been published on the human health effects of cyanobacterial toxicity. as a public health concern, we have to mention that the development of contact dermatitis, asthmalike symptoms, and symptoms resembling hay fever during bathing in cyanobacterial blooms have been also described. microcystis aeruginosa, anabaena flos-aquae, aphanizomenon flos-aquae, and cylindrospermopsis raciborskii are the most common species found in hungarian freshwaters. a sensitization test on albino gu ... | 2001 | 11769249 |
| characterization of human monocyte activation by a water soluble preparation of aphanizomenon flos-aquae. | aphanizomenon flos-aquae (afa) is a fresh-water microalgae that is consumed as a nutrient-dense food source and for its health-enhancing properties. the current research characterizes the effect of a water soluble preparation from afa on human monocyte/macrophage function and compares the effect of afa with responses from known agents that modulate the immune system. at 0.5 pg/ml the afa extract robustly activated nuclear factor kappa b (nf-kappa b) directed luciferase expression in thp-1 human ... | 2001 | 11824519 |
| porphyra-334, a potential natural source for uva protective sunscreens. | the mycosporine-like amino acid (maa), porphyra-334 (lambda(max) = 334 nm; epsilon = 42,300 m(-1) cm(-1)), was isolated from the aquatic cyanobacterium aphanizomenon flos-aquae (afa) and its structure was verified by spectroscopic methods. the uva absorption properties of the crude methanolic extract were determined against two commercial sun care products in terms of mean critical wavelength, mean uva/uvb ratios and uva protection category (boots the chemists, ltd.). the crude methanolic extrac ... | 2006 | 16583025 |
| feeding characteristics of an amoeba (lobosea: naegleria) grazing upon cyanobacteria: food selection, ingestion and digestion progress. | bacterivory by heterotrophic nanoflagellates and ciliates has been widely studied in aquatic environments, but data on the grazing of amoebae, are still scarce. from the water samples of dianchi lake (kunming, yunnan province, china), we isolated an amoeba, designated as naegleria sp. strain w2, which had potent grazing effects on some kind of cyanobacteria. the food selection mechanism and the digestion process of the amoeba were investigated in batch experiments. predation experiments showed t ... | 2006 | 16598635 |
| rdna analyses of planktonic heterocystous cyanobacteria, including members of the genera anabaenopsis and cyanospira. | the taxonomic coherence and phylogenetic relationships of 11 planktonic heterocystous cyanobacterial isolates were examined by investigating two areas of the rrna operon, the 16s rrna gene (rrns) and the internal transcribed spacer (its) located between the 16s rrna and 23s rrna genes. the rrns sequences were determined for five strains, including representatives of anabaena flos-aquae, aphanizomenon flos-aquae, nodularia sp. and two alkaliphilic planktonic members of the genera anabaenopsis and ... | 2002 | 11832512 |
| capillary electrophoretic assay and purification of cylindrospermopsin, a cyanobacterial toxin from aphanizomenon ovalisporum, by plant test (blue-green sinapis test). | toxic cyanobacteria are known to produce cyanotoxins, toxic secondary metabolites. in recent years the cylindrospermopsin (tricyclic guanidinyl hydroxymethyluracil)-producing organisms aphanizomenon ovalisporum, cylindrospermopsis raciborskii, and umezakia natans have been inhabiting polluted fresh waters. cylindrospermopsin, a potent hepatotoxic cyanotoxin, has been implicated in cases of human poisoning as well. this study describes the isolation and purification of cylindrospermopsin from a. ... | 2002 | 11846381 |
| molecular characterization of cyanobacterial diversity in a shallow eutrophic lake. | we have studied the diversity of pelagic cyanobacteria in lake loosdrecht, the netherlands, through recovery and analysis of small subunit ribosomal rna gene sequences from lake samples and cyanobacterial isolates. we used an adapted protocol for specific amplification of cyanobacterial rdna for denaturing gradient gel electrophoresis (dgge) analysis. this protocol enabled direct comparison of cyanobacterial community profiles with overall bacterial profiles. the theoretical amplification specif ... | 2005 | 15683397 |
| alteration of cylindrospermopsin production in sulfate- or phosphate-starved cyanobacterium aphanizomenon ovalisporum. | the effect of sulfate and phosphate deprivation on cell growth and cylindrospermopsin level was studied in aphanizomenon ovalisporum ilc-164. sulfate starvation induced a characteristic reduction of cylindrospermopsin pool size on the basis of cell number and unit of dry mass of culture. phosphorous starvation of a. ovalisporum cultures induced a lesser reduction of cylindrospermopsin pool size. this divergence in the pool size of cylindrospermopsin may be the consequence of different growth rat ... | 2006 | 16734794 |
| detection of microcystin synthetase genes in health food supplements containing the freshwater cyanobacterium aphanizomenon flos-aquae. | in this study we investigated the presence of toxin-producing cyanobacterial contaminants in food supplements manufactured from blooms of the non-toxic freshwater cyanobacterium aphanizomenon flos-aquae. previous reports investigating the contamination of health food supplements with toxin-producing cyanobacteria have used chemical and or biochemical methods such as hplc, elisa and protein phosphatase assays. whilst these studies have drawn attention to the presence of hepatotoxic microcystins i ... | 2005 | 16098554 |
| hepatotoxic cyanobacterial blooms in the lakes of northern poland. | the lakes of northern poland are among the recreational sites most valued by polish and german holiday makers. given the socioeconomic importance of these lakes, water quality should be maintained at high levels for such intensive recreational purposes. in 2002 studies of species composition, biomass, and toxin production by phytoplankton and the attendant physicochemical variables were performed in order to assess the risk of cyanobacterial blooms in selected northern lakes: lakes jeziorak, jag ... | 2005 | 16161103 |
| metabolites produced by cyanobacteria belonging to several species of the family nostocaceae. | this paper provides a comprehensive overview of metabolites, including lipids and lipid-like compounds, nitrogen metabolites, oligopeptides and amino acid derivatives, produced by cyanobacteria of the genera anabaenopsis, aphanizomenon, aulosira, cylindrospermopsis, cylindrospermum, nodularia, and richelia of the family nostocaceae. | 2006 | 17004647 |
| phylogenetic analyses of nitrogen-fixing cyanobacteria from the baltic sea reveal sequence anomalies in the phycocyanin operon. | the examination of molecular phylogenies of cyanobacteria and other micro-organisms is increasing dramatically. the use of a single locus in these studies leaves the resulting phylogenies unconfirmed. in this study, the partial sequences of two loci containing segments of protein-encoding genes, the hetr and the phycocyanin locus (pc-igs), were examined. laboratory strains and natural populations of the heterocyst-forming cyanobacteria anabaena, aphanizomenon and nodularia from the baltic sea we ... | 2002 | 12148656 |
| oral toxicity of the cyanobacterial toxin cylindrospermopsin in mice: long-term exposure to low doses. | the hepatotoxin cylindrospermopsin, a sulfated-guanidinium alkaloid with substituted dioxypyrimidine (uracil) moiety, was isolated from several cyanobacteria species. the acute toxicity of cylindrospermopsin was well established based on intraperitoneal and oral exposure; however, only a few long-term subacute exposure studies were performed to permit a reliable guideline value for cylindrospermopsin in drinking water. in the study reported herein, female and male mice were exposed to cylindrosp ... | 2006 | 17091501 |
| toxicity of complex cyanobacterial samples and their fractions in xenopus laevis embryos and the role of microcystins. | this work evaluated the effects of various cyanobacterial fractions in frog embryo teratogenesis assay xenopus (fetax) with african clawed frog embryos. fractions were prepared from five biomasses with different dominant genera (microcystis, aphanizomenon, anabaena, planktothrix) and different microcystin content. effects of following fractions were investigated: (i) homogenate of complex cyanobacterial biomass, (ii) cell debris (pellet) after centrifugation of complex biomass, (iii) supernatant ... | 2006 | 17092578 |
| phosphorus-limited growth dynamics in two baltic sea cyanobacteria, nodularia sp. and aphanizomenon sp. | rates of carbon (c) specific growth and nitrogen (n2) fixation were monitored in cultures of baltic sea nodularia and aphanizomenon exposed to gradual limitation by inorganic phosphorus (p). both cyanobacteria responded by decreased cellular p content followed by lowered rates of growth and n2 fixation. c-specific growth and cellular n content changed faster in aphanizomenon both when inorganic p was lowered as well as during reintroduction of p. aphanizomenon also showed a more rapid increase i ... | 2006 | 17117977 |
| first report of aphantoxins in china--waterblooms of toxigenic aphanizomenon flos-aquae in lake dianchi. | the oligohaline cyanobacterium aphanizomenon flos-aquae (l.) ralfs (a. flos-aquae) has been reported in several countries to produce paralytic shellfish poisons (psps) or protracted toxic effects. in the past years, a. flos-aquae blooms have occurred annually in the eutrophic lake dianchi (300 km(2) in area, located in southwestern china). material from natural blooms dominated by a. flos-aquae was collected and lyophilized. acute toxicity testing was performed by mouse bioassay using extracts f ... | 2006 | 16289338 |
| effect of different cyanobacterial biomasses and their fractions with variable microcystin content on embryonal development of carp (cyprinus carpio l.). | while numerous studies focused on the effects of microcystins, the role of other components of complex cyanobacterial water blooms in toxicity is poorly understood. in this study we have evaluated effects of various fractions of cyanobacterial biomass with different composition and microcystin content on embryolarval development of carp (cyprinus carpio). the following samples (fractions) of four natural water blooms were prepared and tested: complex cyanobacterial biomass, crude aqueous extract ... | 2007 | 17280727 |
| occurrence of the cyanobacterial toxin cylindrospermopsin in northeast germany. | the frequent occurrence of the cyanobacterial toxin cylindrospermopsin (cyn) in the (sub)tropics has been largely associated with cyanobacteria of the order nostocales of tropical origin, in particular cylindrospermopsis raciborskii. c. raciborskii is currently observed to spread northwards into temperate climatic zones. in addition, further cyanobacteria of the order nostocales typically inhabiting water bodies in temperate regions are being identified as cyn-producers. therefore, data on the d ... | 2007 | 17295278 |
| multiplex pcr assay for cylindrospermopsis raciborskii and cylindrospermopsin-producing cyanobacteria. | water bodies are routinely monitored for the presence of potentially toxic cyanobacteria; however, the methodology for confirming toxicity is currently complex and expensive. here we describe the application of gene-based technology to rapidly identify cylindrospermopsin-producing cyanobacteria, specifically, cylindrospermopsis raciborskii. a multiplex polymerase chain reaction (pcr) test was developed that simultaneously identified polyketide synthase (pks) and peptide synthetase (ps) determina ... | 2003 | 12635100 |
| harmful freshwater algal blooms, with an emphasis on cyanobacteria. | suspended algae, or phytoplankton, are the prime source of organic matter supporting food webs in freshwater ecosystems. phytoplankton productivity is reliant on adequate nutrient supplies; however, increasing rates of nutrient supply, much of it manmade, fuels accelerating primary production or eutrophication. an obvious and problematic symptom of eutrophication is rapid growth and accumulations of phytoplankton, leading to discoloration of affected waters. these events are termed blooms. bloom ... | 2001 | 12805693 |
| isolation and endotoxin activities of lipopolysaccharides from cyanobacterial cultures and complex water blooms and comparison with the effects of heterotrophic bacteria and green alga. | massive cyanobacterial water blooms are serious environmental and health problems worldwide. while some cyanobacterial toxins such as peptide microcystins have been investigated extensively, other toxic components of cyanobacteria (e.g. lipopolysaccharides, lps) are poorly understood. the present study characterized endotoxin activities of lps isolated from (i) laboratory cyanobacterial cultures, (ii) cyanobacterial water bloom samples dominated by microcystis sp., planktothrix sp., aphanizomeno ... | 2008 | 17461433 |
| [effect of aphanizomenon flos-aquae toxins on some blood physiological parameters in mice]. | in order to study the toxic effect of stx on mouse's blood with time lapse, stx from aphanizomenon flosaquae was collected and the effect of toxins on physiological parameters of blood was measured by analyzing changes in cells and components in blood. results showed that the blood parameters in mice changed after 0.5, 6, 12 and 24 hours respectively when mice were exposed to 0.5 mu/ml saxitoxin (stx). the numbers of red blood cell, hemoglobin and platelet had little changed, while the number of ... | 2003 | 12914277 |
| associations of cyanobacterial toxin, nodularin, with environmental factors and zooplankton in the baltic sea. | concentrations of a cyanobacterial toxin, nodularin, were measured in the baltic sea in 1998 and 1999. statistical associations of nodularin concentrations with environmental factors were tested by multiple regression analysis. to reveal the toxin-producing organism, colonies of aphanizomenon and filaments of nodularia were picked and analyzed for peptide toxins. it was also investigated whether there was an association with zooplankton and nodularia. all the measured seston samples contained no ... | 2004 | 14681737 |
| direct evidence for production of microcystins by anabaena strains from the baltic sea. | anabaena is a filamentous, n(2)-fixing, and morphologically diverse genus of cyanobacteria found in freshwater and brackish water environments worldwide. it contributes to the formation of toxic blooms in freshwater bodies through the production of a range of hepatotoxins or neurotoxins. in the baltic sea, anabaena spp. form late summer blooms, together with nodularia spumigena and aphanizomenon flos-aquae. it has been long suspected that baltic sea anabaena may produce microcystins. the presenc ... | 2007 | 17766456 |
| accumulation and depuration of cyanobacterial paralytic shellfish toxins by the freshwater mussel anodonta cygnea. | the increasing frequency by which the production of paralytic shellfish toxins (pst) by freshwater bloom-forming cyanobacteria is being noticed world-wide raises the possibility of pst bioaccumulation by freshwater mussels. this study evaluates pst accumulation and depuration by the freshwater mussel anodonta cygnea exposed over a 14-day period to high densities (mean = 1.4 x 10(9) cells1(-1), s.d. = 0.29 x 10(9) cellsl(-1)) of the toxic cyanobacterium aphanizomenon issatschenkoi (corresponding ... | 2004 | 15177951 |
| natural killer cell activation and modulation of chemokine receptor profile in vitro by an extract from the cyanophyta aphanizomenon flos-aquae. | the present research was designed to study the effects of an extract from the edible cyanophyta aphanizomenon flos-aquae on human natural killer (nk) cells. we have previously shown, using a double-blind randomized placebo-controlled crossover design, that ingestion of 1.5 g of dried whole a. flos-aquae resulted in a transient reduction in peripheral blood nk cells in 21 healthy human volunteers, suggesting increased nk cell homing into tissue. we have now identified an extract from a. flos-aqua ... | 2007 | 17887936 |
| activation of autoimmunity following use of immunostimulatory herbal supplements. | evidence for the scientific basis of purported therapeutic effects and adverse effects of herbal supplements continues to grow. many herbal supplements are touted for their immunostimulatory properties, and both in vitro and in vivo experiments have supported this claim. although this explains their beneficial effects in preventing or curtailing disease, to our knowledge, no immunostimulatory herbal supplements have been reported to exacerbate disorders of immune system overactivity. | 2004 | 15210464 |
| antioxidant properties of a novel phycocyanin extract from the blue-green alga aphanizomenon flos-aquae. | aphanizomenon flos-aquae (afa) is a fresh water unicellular blue-green alga (cyanophyta) rich in phycocyanin (pc), a photosynthetic pigment with antioxidant and anti-inflammatory properties. the purpose of this study was to evaluate the ability of a novel natural extract from afa enriched with pc to protect normal human erythrocytes and plasma samples against oxidative damage in vitro. in red blood cells, oxidative hemolysis and lipid peroxidation induced by the aqueous peroxyl radical generator ... | 2004 | 15350832 |
| accumulation of paralytic shellfish toxins (pst) from the cyanobacterium aphanizomenon issatschenkoi by the cladoceran daphnia magna. | in order to access the effects of paralytic shellfish toxins (pst) in freshwater environment, the accumulation of pst produced by the cyanobacteria aphanizomenon issatschenkoi in juvenile daphnia magna was investigated. d. magna was exposed to a. issatschenkoi cells (1.2 x 10(6) cells ml(-1)) for 6, 8, 12, 24 and 30 h and also to lyophilised material (1 mg ml(-1)) for 24h. survival and somatic growth of the juvenile d. magna was investigated, as was the activity of the biotransformation enzyme s ... | 2004 | 15500853 |
| toxic cyanobacteria strains isolated from blooms in the guadiana river (southwestern spain). | this paper describes the occurrence of toxic cyanobacteria along the guadiana river over its course between mérida and badajoz (extremadura, spain). water sampling for phytoplankton quantification and toxin analysis was carried out regularly between 1999 and 2001 in six different locations, including two shallow, slow-flowing river sites, two streamed river sites and two drinking water reservoirs. the cyanobacterial community differed significantly between these locations, especially during the ... | 2004 | 15515966 |
| testing of primers for the study of cyanobacterial molecular diversity by dgge. | denaturing gradient gel electrophoresis (dgge) is a pcr-based technique which is widely used in the study of microbial communities. here, the use of the three specific 16s rrna cyanobacterial specific primers cya359f, cya781r(a) and cya781r(b) on the assessment of the molecular diversity of cyanobacterial communities is examined. assignments of the reverse primers cya781r(a) and cya781r(b) with cyanobacterial strain sequences showed that the former preferentially targets filamentous cyanobacteri ... | 2006 | 16290299 |
| alternative remedies may activate autoimmune disorders. | | 2004 | 15551470 |
| selection on protein-coding genes of natural cyanobacterial populations. | we examined the distribution of synonymous and non-synonymous changes in 12 protein-coding genes of natural populations of cyanobacteria to infer changes in gene functionality. by comparing mutation distributions within and across species using the mcdonald-kreitman test, we found data sets to contain evidence for purifying selection (hetr of trichodesmium, nifh of cylindrospermopsis raceborskii and rpoc1 of anabaena lemmermannii) and positive selection (kaic of microcoleus chthonoplastes and rb ... | 2006 | 16913914 |
| multiplex pcr for the detection of toxigenic cyanobacteria in dietary supplements produced for human consumption. | the production of food supplements containing cyanobacteria is a growing worldwide industry. while there have been several reports of health benefits that can be gained from the consumption of these supplements, there have also been a growing number of studies showing the presence of toxins some of which (for example microcystins) are known to affect human health. in this paper, we report a multiplex polymerase chain reaction (pcr) technique that can be used to identify microcystin contamination ... | 2007 | 17001477 |
| effects of cylindrospermopsis raciborskii and aphanizomenon ovalisporum (cyanobacteria) ingestion on daphnia magna midgut and associated diverticula epithelium. | this article reports a light and electron microscopy investigation of the effects of cylindrospermopsis raciborskii and aphanizomenon ovalisporum ingestion on midgut and associated digestive diverticula of daphnia magna. additionally, survivorship and growth effects caused by feeding on cyanobacteria were assessed. three cyanobacteria were used in the experiments: cylindrospermopsin (cyn)-producing c. raciborskii, cyn-producing a. ovalisporum and non-cyn-producing c. raciborskii. in order to dis ... | 2006 | 17010452 |
| purification and characterization of a corrinoid-compound in an edible cyanobacterium aphanizomenon flos-aquae as a nutritional supplementary food. | the vitamin b12 concentration of the dried cells of aphanizomenon flos-aquae was determined by both microbiological method with lactobacillus delbrueckeii atcc7830 and chemiluminescence method with intrinsic factor. the aphanizomenon cells contained 616.3 +/- 30.3 micro g (n = 4) of vitamin b12 per 100 g of the dried cells by the microbiological method. the values determined with the chemiluminescence method, however, were only about 5.3% of the values determined by the microbiological method. a ... | 2006 | 17147452 |