Blue-green Alga Aphanizomenon Flos-aquae Research Articles

Physiological and morphological response of Aphanizomenon flos-aquae to watermelon (Citrullus lanatus) peel aqueous extract

Natural algaecides are more likely to be specific and biodegradable, and may offer an environmentally friendly method for control of cyanobacterial blooms. We explored, for the first time, the potential for watermelon peel aqueous extract (WMPAE) to control the growth of the harmful blue-green alga Aphanizomenon flos-aquae. The growth inhibition and several physiological parameters of A. flos-aquae, in response to WMPAE, were analyzed. Results showed that WMPAE significantly inhibited the growth of A. flos-aquae in a concentration-dependent way. The highest inhibition reached 94 % after 3 days’ treatment with 6 g L−1 of WMPAE and a significant effect was obtained with lower doses and shorter times as well. The cell viability decreased quickly, cell shape changed, and intracellular structural damage occurred. At the same time, the antioxidant enzymes (superoxide dismutase SOD, catalase CAT and peroxidase POD) and malondialdehyde (MDA) levels all increased significantly, indicating that WMPAE between 2–6 g L−1 induced severe oxidative stress and damage to A. flos-aquae. Moreover, production of the four pigments chlorophyll a (Chl a), carotenoids, phycocyanin (PC), and allophycocyanin (APC) were all stimulated, though photosynthesis of A. flos-aquae was clearly inhibited. The maximum quantum yield of photosystem II (Fv/Fm) and the effective quantum yield of photosystem II ( Fv'/Fm') declined sharply, suggesting the decreased photosystem capacity of A. flos-aquae to convert light energy into chemical energy. In addition, non-photochemical quenching (NPQ) of A. flos-aquae increased after a very short time exposure to WMPAE, and decreased significantly with prolonged exposure time, which indicated the failure of photo protection mechanisms. These results suggest that the loss of cell viability, and increases in oxidative stress, and damage to intracellular structure and photosynthetic systems might be the mechanisms for the inhibitory effects. Our results suggested that WMPAE could be a novel and effective approach for controlling the growth of A. flos-aquae in aquatic environments.

In vitro antioxidant, anti-glycation and immunomodulation activities of fermented blue-green algae Aphanizomenon flos-aquae.

To clarify the antioxidant, anti-glycation and immunomodulatory capacities of fermented blue-green algae Aphanizomenon flos-aquae (AFA), hot aqueous extract suspensions made from 10% AFA were fermented by Lactobacillus plantarum AN7 and Lactococcus lactis subsp. lactis Kushiro-L2 strains isolated from a coastal region of Japan. The DPPH and O2- radical scavenging capacities and Fe-reducing power were increased in the fermented AFA. The increased DPPH radical scavenging capacity of the fermented AFA was fractionated to mainly < 3kDa and 30-100kDa. The increased O2- radical scavenging capacities were fractionated to mainly < 3kDa. Anti-glycation activity in BSA-fructose model rather than BSA-methylglyoxal model was increased by the fermentation. The increased anti-glycation activity was fractionated to mainly 30-100kDa. The NO concentration in the murine macrophage RAW264.7 culture media was high with the fermented AFA. The increased immunomodulation capacity was also fractionated to mainly 30-100kDa. These results suggest that the fermented AFA is a more useful material for health foods and supplements.

Subchronic toxicity (90 days) of StemEnhance&amp;trade; in Wistar rats

Subchronic toxicity (90 days) of StemEnhance&trade; in Wistar rats Levent Dirikolu1, Thushara Chakkath1, Susan Ball-Kell2, Christy Elamma2, David J Schaeffer11Department of Comparative Biosciences, 2Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Illinois at Urbana-Champaign, Urbana, IL, USAAbstract: This study evaluated the subchronic toxicity of StemEnhance&trade;, an extract of the blue-green alga Aphanizomenon flos-aquae that is used as a health supplement. Groups of 12 rats of each sex were given either 5% glycerin in water (control) or 200 mg/kg of StemEnhance prepared in 5% glycerin in water for 90 days by oral gavage. The administration of StemEnhance had no effect on behavior, food and water intake, growth, or survival. Values at the end of dosing and observation periods did not reveal differences between treated and control groups for hematology and clinical chemistry. There were no significant differences in the gross and histopathology of the reproductive organs in either males or females. Sperm motility parameters were similar for control and treated males. Our results show that StemEnhance at doses ~7 times the maximum label-recommended daily dose did not produce adverse effects in Wistar rats after subchronic treatment.Keywords: algal toxicology, blue-green algae, cyanobacteria, Aphanizomenon flos-aquae

Subacute toxicity study in Wistar rats fed with StemEnhanceTM, an extract from Aphanizomenon flos-aquae

correspondence: Levent Dirikolu Department of comparative Biosciences, college of Veterinary Medicine, University of illinois at Urbanachampaign, 3830 VMBSB, 2001 South Lincoln Avenue, Urbana, iL 61802, USA Tel +1 217 244 4439 Fax +1 217 244 1652 email dirikolu@illinois.edu Abstract: This study evaluated the safety (absence of toxicity) of StemEnhanceTM, an extract of the blue-green alga Aphanizomenon flos-aquae that is used as a health supplement. Groups of 12 rats of each sex were given either 5% glycerin in water (control) or 600 mg/kg of StemEnhance prepared in 5% glycerin in water for 2 weeks by oral gavage followed by 2 weeks of observation. The administration of StemEnhance had no effect on behavior, food and water intake, growth, or survival. Values at the end of dosing and observation periods did not reveal differences between treated and control groups for hematology and clinical chemistry. There were no significant differences in the gross and histopathology of the reproductive organs in either males or females. Sperm motility parameters were similar for control and treated males. Our results show that StemEnhance at doses ∼20 times the maximum label-recommended daily dose did not produce adverse effects in Wistar rats after subacute treatment.

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 [2,2′-Azobis (2-amidinopropane) dihydrochloride, AAPH] were significantly lowered by the AFA extract in a time- and dose-dependent manner; at the same time, the depletion of cytosolic glutathione was delayed. In plasma samples, the natural extract inhibited the extent of lipid oxidation induced by the pro-oxidant agent cupric chloride (CuCl 2); a concomitant increase of plasma resistance to oxidation was observed as evaluated by conjugated diene formation. The involvement of PC in the antioxidant protection of the AFA extract against the oxidative damage was demonstrated by investigating the spectral changes of PC induced by AAPH or CuCl 2. The incubation of the extract with the oxidizing agents led to a significant decrease in the absorption of PC at 620 nm accompanied with disappearance of its blue color, thus indicating a rapid oxidation of the protein. In the light of these in vitro results, the potential clinical applications of this natural compound are under investigation.

A New Route to (-)-Aphanorphine Using a Dioxabicyclo[3.2.1]octane Chiral Building Block

A new stereocontrolled route to (-)-aphanorphine, isolated from the fresh-water blue-green algae Aphanizomenon flos-aquae has been developed by using a chiral building block having a dioxabicyclo[3.2. 1]octane framework and originally designed for the construction of the aldohexose molecules.

Aphanorphine, a novel tricyclic alkaloid from the blue-green alga Aphanizomenon flos-aquae

An alkaloid with a benzazepine skeleton, aphanorphine ( 1) was isolated from the blue-green alga, Aphanizomenon flos-aquae together with its previously known constituents neosaxitoxin and saxitoxin.

Zur Ökologie der planktischen BlaualgeAphanizomenon flosaquae in Alpenrandseen

With help of field data from several alpine lakes and results from culture studies [54] an attempt was made to describe the conditions necessary for the occurrence of the blue-green algaAphanizomenon flosaquae in a lake. Special attention was paid to temperature, phosphorus, nitrogen and light.

Blue-green algae in the sediment of the Lake Brielse Meer

It was demonstrated that the blue-green algaeAphanizomenon flosaquae, Microcystis aeruginosa, Oscillatoria agardhii andO. tenuis are present throughout the year in the sediment of an eutrophic dutch lake.Anabaena flos-aquae does not have a benthic phase.

Purification of Aphanizomenon flos-aquae toxin and its chemical and physiological properties

A toxin in chromatographically pure form has been isolated from natural blooms of the blue-green alga Aphanizomenon flos-aquae. The toxin is a strongly basic substance, which gives a positive ninhydrin reaction and appears to be a guanidine derivative. A dose of 2·7 μg injected intraperitoneally into 20 g mice caused death in 4·9 min. The purified toxin reversibly blocks action potentials and tension development in amphibian nerve-muscle preparations without alteration of the resting potential. The toxin differs from saxitoxin in some of its chemical and physical properties, and some of its effects on neuromuscular systems.

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.

Observations on the Growth and Colony Habits of Ten Strains of Aphanizomenon flos-aquae

Ten strains of the blue-green alga Aphanizomenon flos-aquae were obtained in unialgal culture by isolating single colonies from samples of waterbloom collected in south central Saskatchewan and eastern Ontario. Two strains from Saskatchewan produced large, ribbon-like colonies up to 30 mm long and 5 to 6 mm wide in a medium containing two different preparations of soil extract. Both strains produced typical small colonies in medium without soil extract or with other soil extract preparations. The large colonies produced by these strains were similar to those observed in plankton from south central Saskatchewan, Oregon, southern Germany, and Russia. Eight strains from Ontario produced only typical small colonies under identical or comparable conditions. After a prolonged period of growth in soil extract medium, all strains became partially or completely non-colonial. Soil extract was not essential for growth. Differences in the colony habit of the 10 strains in soil extract medium or of colonies observed in plankton samples could not be correlated with differences in cellular dimensions or appearance. Colony habit appears to depend on genetic and nutritional factors which may involve the associated bacterial flora as well as the alga.