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Malcolm Potts - One of the best experts on this subject based on the ideXlab platform.
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uv irradiation and desiccation modulate the three dimensional extracellular matrix of Nostoc Commune cyanobacteria
Journal of Biological Chemistry, 2005Co-Authors: Deborah J Wright, Sue C Smith, Vinita Joardar, Jody Jervis, Andrew Warren, Siegfried Scherer, Richard F Helm, Malcolm PottsAbstract:Abstract Cyanobacterium Nostoc Commune can tolerate the simultaneous stresses of desiccation, UV irradiation, and oxidation. Acidic WspA, of ∼33.6 kDa, is secreted to the three-dimensional extracellular matrix and accounts for greater than 70% of the total soluble protein. The wspA gene of N. Commune strain DRH1 was cloned and found in a single genomic copy, in a monocistronic operon. Transcription of wspA and sodF (superoxide dismutase), and synthesis and secretion of WspA, were induced upon desiccation or UV-A/B irradiation of cells. Recombinant WspA binds the UV-A/B absorbing pigment scytonemin through non-covalent interactions. WspA peptide polymorphism, and heterogeneity of multiple wspA sequences within cells of a single colony, account for distinct WspA isoforms. WspA has no similarity to entries in the sequence databases and wspA, a possible xenolog, is restricted to a subset of strains in the “form species” N. Commune characterized through group I intron phylogeny. We hypothesize that WspA plays a central role in the global stress response of N. Commune through modulation of the structure and function of the three-dimensional extracellular matrix, particularly the transport, distribution, and/or macromolecular architecture of mycosporine and scytonemin UV-A/B absorbing pigment complexes.
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unusual water flux in the extracellular polysaccharide of the cyanobacterium Nostoc Commune
Applied and Environmental Microbiology, 2003Co-Authors: Eric Shaw, Richard F Helm, Donna R Hill, Nicole Brittain, Debbie J Wright, Uwe C Tauber, Herve Marand, Malcolm PottsAbstract:The speed of water uptake by desiccated Nostoc Commune was found to depend upon the duration of desiccation. The rehydration of desiccated colonies led to marked, time-dependent changes in structure and ultrastructure and fluctuations in the composition of the transcriptome. Physical evaporative water loss is an active process that was influenced by inhibitors of transcription and translation.
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form species Nostoc Commune cyanobacteria
International Journal of Systematic and Evolutionary Microbiology, 2001Co-Authors: Deborah J Wright, Richard F Helm, Todd Prickett, Malcolm PottsAbstract:The form species concept for the Cyanobacteria was evaluated using a comprehensive set of Nostoc samples that were collected during the past two centuries, from all continents, including regions from the Tropics to the Poles. Phylogenies were constructed based upon the conserved regions of tRNALeu (UAA) group I intron DNA sequences. Thirty-four forms contained a tRNALeu (UAA) intron of 284 nt. These 284-nt introns contained 200 nt of conserved sequence that, in most cases, shared 100% sequence identity, they had three variable regions (I, II and III) amounting to 84 nt, contained no hypervariable region and formed a discrete cluster in phylogenetic analysis. These forms represented 31 independent populations in both hemispheres and constitute examples of form species Nostoc Commune. Multiple introns were obtained from several of the populations. Ten populations contained introns of 287-340 nt with a hypervariable region, 8 to 59 nt in length, located between variable regions I and II. Alignments identified 15 examples where 5'-AAAAUCC-3' occurred at the hypervariable region-variable region II boundary; this sequence is identical to the conserved sequence at the 3' intron-exon boundary (splice site) within the tRNALeu (UAA) gene. The possibility that hypervariable regions were removed from the primary intron through secondary splicing was tested in vitro but proved to be negative under the experimental conditions used. Shared morphologies of genetically different strains, dissimilar morphologies in strains that share identical genetic markers, incorrect naming of culture collection strains and genetic drift in cultured strains emphasize that the successful delineation of cyanobacterial species requires the application of multiple taxonomic criteria.
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structural characterization of the released polysaccharide of desiccation tolerant Nostoc Commune drh 1
Journal of Bacteriology, 2000Co-Authors: Richard F Helm, Zebo Huang, Devin Edwards, Heidi Leeson, William Peery, Malcolm PottsAbstract:The structure of the viscous extracellular polysaccharide (glycan) of desiccation-tolerant Nostoc Commune DRH-1 was determined through chromatographic and spectroscopic methods. The polysaccharide is novel in that it possesses a 1-4-linked xylogalactoglucan backbone with d-ribofuranose and 3-O-[(R)-1-carboxyethyl]-d-glucuronic acid (nosturonic acid) pendant groups. The presence of d-ribose and nosturonic acid as peripheral groups is unusual, and their potential roles in modulating the rheological properties of the glycan are discussed. Nosturonic acid was present in the glycans of N. Commune from diverse geographic locations, suggesting that this uronic acid is an integral component of this cosmopolitan anhydrophile.
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extracellular polysaccharide of Nostoc Commune cyanobacteria inhibits fusion of membrane vesicles during desiccation
Journal of Applied Phycology, 1997Co-Authors: Donna R Hill, Malcolm Potts, Richard F Helm, Thomas W Keenan, Lois M Crowe, John H CroweAbstract:Cells of the cyanobacterium Nostoc Commune secrete a complex, high molecular weight, extracellular polysaccharide (EPS) which accumulates to more than 60% of the dry weight of colonies. The EPS was purified from the clonal isolate N. Commune DRH1. The midpoint of the membrane phase transition (Tm) of desiccated cells of N. Commune CHEN was low (Tm dry = 8 °C) and was comparable to the Tm of rehydrated cells((Tm)H20 = 6 °C). The EPS was not responsible for the depression of Tm. However, the EPS, at low concentrations, inhibited specifically the fusion of phosphatidylcholine membrane vesicles when they were dried in vitro at0% relative humidity (−400 MPa). Low concentrations of a trehalose:sucrose mixture, in a molar ratio which corresponded with that present in cells in vivo, together with small amounts of the EPS, were efficient in preventing leakage of carboxyfloroscein (CF) from membrane vesicles. Freeze-fracture electron microscopy resolved complex changes in the structure of the EPS and the outer membrane in response to rehydration of desiccated cells. The capacity of the EPS to prevent membrane fusion, the maintenance of a low Tm dry in desiccated cells, and the changes in rheological properties of the EPS in response to water availability, constitute what are likely important mechanisms for desiccation tolerance in this cyanobacterium.
Toshio Sakamoto - One of the best experts on this subject based on the ideXlab platform.
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characterization of mycosporine like amino acids in the edible cyanobacterium Nostoc Commune di pi cai from china
Journal of General and Applied Microbiology, 2021Co-Authors: Yang Wei, Takumi Nishiuchi, Toshio SakamotoAbstract:The terrestrial cyanobacterium Nostoc Commune has a cosmopolitan distribution. It is edible, and dry thalli are sold as a food in China under the name of Di Pi Cai. The pigment composition and the genotypes were characterized to identify the cyanobacterium Di Pi Cai from China as N. Commune. Myxol glycosides and ketocarotenoids were detected, as expected in Nostoc sp., but β-carotene and hydroxylated carotenoids were not detected. Nostoc-756, mycosporine-2-(4-deoxygadusoyl-ornitine), was found to be a main mycosporine-like amino acid, which indicates that Di Pi Cai belongs to the N. Commune chemotype C. However, the 16S rRNA gene and the petH gene encoding ferredoxin-NADP+ oxidoreductase of Di Pi Cai did not exactly match those of genotype C found in Japan. These results suggest the unique molecular genetic features of Di Pi Cai and the global diversity of N. Commune.
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characterization of extracellular matrix components from the desiccation tolerant cyanobacterium Nostoc Commune
Journal of General and Applied Microbiology, 2017Co-Authors: Kaori Inouesakamoto, Minami Yamaba, Tomoya Asano, Takumi Nishiuchi, Yasunori Tanji, Takumi Natsume, Takuya Masaura, Toshio SakamotoAbstract:The terrestrial cyanobacterium Nostoc Commune forms macroscopic colonies in its natural habitats, and these colonies consist of both cellular filaments and massive extracellular matrixes. In this study, the biochemical features of the extracellular matrix components were investigated. Naturally growing N. Commune was tolerant to desiccation, and produced massive extracellular polysaccharides that contained both neutral sugars and glucuronic acid as constituent monosaccharides. The extracellular polysaccharide contents and desiccation tolerance were compared in laboratory culture strains of Nostoc species. The laboratory culture of N. Commune strain KU002 was sensitive to desiccation and produced smaller amounts of extracellular polysaccharides, unlike the field-isolated naturally growing colonies. Nostoc punctiforme strain M-15, which is genetically closed to N. Commune, was able to tolerate desiccation, although the other Nostoc strains were desiccation-sensitive. A laboratory culture strain of the aquatic cyanobacterium Nostoc sphaericum produced massive extracellular polysaccharides but was sensitive to desiccation, suggesting that extracellular matrix production is not enough to make this strain tolerant to desiccation. WspA (water stress protein) and SodF (superoxide dismutase) were found to be characteristic protein components of the extracellular matrix of N. Commune. Because the WspA proteins were heterogeneous, the wspA genes were highly diverse among the different genotypes of N. Commune, although the sodF gene was rather conservative. The heterogeneity of the WspA proteins suggests their complex roles in the environmental adaptation mechanism in N. Commune.
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characterization of the chemical diversity of glycosylated mycosporine like amino acids in the terrestrial cyanobacterium Nostoc Commune
Journal of Photochemistry and Photobiology B-biology, 2015Co-Authors: Ehsan Nazifi, Naoki Wada, Seiichi Matsugo, Tomoya Asano, Takumi Nishiuchi, Yoshiaki Iwamuro, Satoshi Chinaka, Toshio SakamotoAbstract:Abstract Mycosporine-like amino acids (MAAs) are UV-absorbing pigments, and structurally unique glycosylated MAAs are found in the terrestrial cyanobacterium Nostoc Commune. In this study, we examined two genotypes of N. Commune colonies with different water extract UV-absorption spectra. We found structurally distinct MAAs in each genotype. The water extract from genotype A showed a UV-absorbing spectrum with an absorption maximum at 335 nm. The extract contained the following compounds: 7-O-(β-arabinopyranosyl)-porphyra-334 (478 Da), pentose-bound shinorine (464 Da), hexose-bound porphyra-334 (508 Da) and porphyra-334 (346 Da). The water extract from genotype B showed a characteristic UV-absorbing spectrum with double absorption maxima at 312 and 340 nm. The extract contained hybrid MAAs (1050 Da and 880 Da) with two distinct chromophores of 3-aminocyclohexen-1-one and 1,3-diaminocyclohexen linked to 2-O-(β-xylopyranosyl)-β-galactopyranoside. A novel 273-Da MAA with an absorption maximum at 310 nm was also identified in genotype B. The MAA consisted of a 3-aminocyclohexen-1-one linked to a γ-aminobutyric acid chain. These MAAs had potent radical scavenging activities in vitro and the results confirmed that the MAAs have multiple roles as a UV protectant and an antioxidant relevant to anhydrobiosis in N. Commune. The two genotypes of N. Commune exclusively produced their own characteristic glycosylated MAAs, which supports that MAA composition could be a chemotaxonomic marker for the classification of N. Commune.
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glycosylated porphyra 334 and palythine threonine from the terrestrial cyanobacterium Nostoc Commune
Marine Drugs, 2013Co-Authors: Ehsan Nazifi, Naoki Wada, Seiichi Matsugo, Minami Yamaba, Tomoya Asano, Takumi Nishiuchi, Toshio SakamotoAbstract:Mycosporine-like amino acids (MAAs) are water-soluble UV-absorbing pigments, and structurally different MAAs have been identified in eukaryotic algae and cyanobacteria. In this study novel glycosylated MAAs were found in the terrestrial cyanobacterium Nostoc Commune (N. Commune). An MAA with an absorption maximum at 334 nm was identified as a hexose-bound porphyra-334 derivative with a molecular mass of 508 Da. Another MAA with an absorption maximum at 322 nm was identified as a two hexose-bound palythine-threonine derivative with a molecular mass of 612 Da. These purified MAAs have radical scavenging activities in vitro, which suggests multifunctional roles as sunscreens and antioxidants. The 612-Da MAA accounted for approximately 60% of the total MAAs and contributed approximately 20% of the total radical scavenging activities in a water extract, indicating that it is the major water-soluble UV-protectant and radical scavenger component. The hexose-bound porphyra-334 derivative and the glycosylated palythine-threonine derivatives were found in a specific genotype of N. Commune, suggesting that glycosylated MAA patterns could be a chemotaxonomic marker for the characterization of the morphologically indistinguishable N. Commune. The glycosylation of porphyra-334 and palythine-threonine in N. Commune suggests a unique adaptation for terrestrial environments that are drastically fluctuating in comparison to stable aquatic environments.
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novel glycosylated mycosporine like amino acids with radical scavenging activity from the cyanobacterium Nostoc Commune
Journal of Photochemistry and Photobiology B-biology, 2011Co-Authors: Kei Matsui, Ehsan Nazifi, Shinpei Kunita, Naoki Wada, Seiichi Matsugo, Toshio SakamotoAbstract:Abstract Mycosporine-like amino acids (MAAs) are UV absorbing pigments, and structurally distinct MAAs have been identified in taxonomically diverse organisms. Two novel MAAs were purified from the cyanobacterium Nostoc Commune, and their chemical structures were characterized. An MAA with an absorption maximum at 335 nm was identified as a pentose-bound porphyra-334 derivative with a molecular mass of 478 Da. Another identified MAA had double absorption maxima at 312 and 340 nm and a molecular mass of 1050 Da. Its unique structure consisted of two distinct chromophores of 3-aminocyclohexen-1-one and 1,3-diaminocyclohexen and two pentose and hexose sugars. These MAAs had radical scavenging activity in vitro; the 1050-Da MAA contributed approximately 27% of the total radical scavenging activities in a water extract of N. Commune. These results suggest that these glycosylated MAAs have multiple roles as a UV protectant and an antioxidant relevant to anhydrobiosis in N. Commune.
García Bartra, Sweeney Kahomy - One of the best experts on this subject based on the ideXlab platform.
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Efecto de la sustitución parcial de grenetina por harina de cushuro (Nostoc Commune vauch) sobre las características nutricionales y físicas de gomitas comestibles a base de arándano (Vaccinium myrtillus)
'Universidad Cesar Vallejo', 2020Co-Authors: García Bartra, Sweeney KahomyAbstract:El presente trabajo de investigación tuvo por objetivo la evaluación del efecto de la sustitución parcial de grenetina por harina de cushuro (Nostoc Commune vauch) sobre las características nutricionales y físicas de gomitas comestibles a base de arándano (Vaccinium myrtillus). Se realizaron 3 porcentajes de sustitución teniendo como T1 al 35 %, T2 al 45% y T3 al 55% de sustitución de harina de cushuro al cual se le realizó las características nutricionales dando como resultado un 3.1433 % de proteínas, 0.146 % de cenizas, 10.026 % de grasa, 74.442 % de carbohidratos, aportando 400.584 Kcal por cada 100 g, con un aporte de antioxidantes en un 54.616%, para el tratamiento 1, un 3.180 % de proteínas, 0.0780 % de cenizas, 4.884 % de grasa, 78.422 % de carbohidratos, aportando 320.371 Kcal por cada 100 g, con un aporte de antioxidantes en un 58.951%, para el tratamiento 2, un 3.457 % de proteínas, 0.398 % de cenizas, 3.709 % de grasa, 82.284 % de carbohidratos, aportando 376.35 Kcal por cada 100 g, con un gran aporte de antioxidantes en un 66.646%, para el tratamiento 3, en cuanto a las características físicas se obtuvo para el tratamiento 1: 0.801 N de fuerza a la compresión, con una humedad de 12.24 % y en cuanto a color con una luminosidad de L* 33.706, a*0.8467, b*0.01, c*0.8467 y ΔE de 1.845, en el tratamiento 2: 0.464 N de fuerza a la compresión, con un porcentaje de humedad en 13.434 % y en cuanto a color con una luminosidad de L* 33.713, a*0.446, b*0.116, c*0.463y ΔE de 1.432 y por último para el tratamiento 3: 0.316 N de fuerza a la compresión, con un porcentaje de humedad en 10.150 % siendo este el más bajo y en cuanto a color presenta una luminosidad de L* 28.48, a*0.7, b*0.773, c*1.0433 y ΔE de 2.2435. En conclusión, se obtuvieron mejores características fisicoquímicas con el tercer tratamiento (55%) en las gomitas comestibles a base de cushuro (Nostoc Commune vauch) y arándano (Vaccinium myrtillus), por otro lado, el tratamiento 1 (35%) presentó mejores resultados en cuanto a características físicas
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Efecto de la sustitución parcial de grenetina por harina de cushuro (Nostoc Commune vauch) sobre las características nutricionales y físicas de gomitas comestibles a base de arándano (Vaccinium myrtillus)
'Universidad Cesar Vallejo', 2020Co-Authors: García Bartra, Sweeney KahomyAbstract:TesisTrujilloEscuela Académico Profesional de Ingeniería AgroindustialProcesos AgroindustrialesEl presente trabajo de investigación tuvo por objetivo la evaluación del efecto de la sustitución parcial de grenetina por harina de cushuro (Nostoc Commune vauch) sobre las características nutricionales y físicas de gomitas comestibles a base de arándano (Vaccinium myrtillus). Se realizaron 3 porcentajes de sustitución teniendo como T1 al 35 %, T2 al 45% y T3 al 55% de sustitución de harina de cushuro al cual se le realizó las características nutricionales dando como resultado un 3.1433 % de proteínas, 0.146 % de cenizas, 10.026 % de grasa, 74.442 % de carbohidratos, aportando 400.584 Kcal por cada 100 g, con un aporte de antioxidantes en un 54.616%, para el tratamiento 1, un 3.180 % de proteínas, 0.0780 % de cenizas, 4.884 % de grasa, 78.422 % de carbohidratos, aportando 320.371 Kcal por cada 100 g, con un aporte de antioxidantes en un 58.951%, para el tratamiento 2, un 3.457 % de proteínas, 0.398 % de cenizas, 3.709 % de grasa, 82.284 % de carbohidratos, aportando 376.35 Kcal por cada 100 g, con un gran aporte de antioxidantes en un 66.646%, para el tratamiento 3, en cuanto a las características físicas se obtuvo para el tratamiento 1: 0.801 N de fuerza a la compresión, con una humedad de 12.24 % y en cuanto a color con una luminosidad de L* 33.706, a*0.8467, b*0.01, c*0.8467 y ΔE de 1.845, en el tratamiento 2: 0.464 N de fuerza a la compresión, con un porcentaje de humedad en 13.434 % y en cuanto a color con una luminosidad de L* 33.713, a*0.446, b*0.116, c*0.463y ΔE de 1.432 y por último para el tratamiento 3: 0.316 N de fuerza a la compresión, con un porcentaje de humedad en 10.150 % siendo este el más bajo y en cuanto a color presenta una luminosidad de L* 28.48, a*0.7, b*0.773, c*1.0433 y ΔE de 2.2435. En conclusión, se obtuvieron mejores características fisicoquímicas con el tercer tratamiento (55%) en las gomitas comestibles a base de cushuro (Nostoc Commune vauch) y arándano (Vaccinium myrtillus), por otro lado, el tratamiento 1 (35%) presentó mejores resultados en cuanto a características físicas
Youngki Park - One of the best experts on this subject based on the ideXlab platform.
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in vitro and in vivo safety assessment of edible blue green algae Nostoc Commune var sphaeroides kutzing and spirulina plantensis
Food and Chemical Toxicology, 2011Co-Authors: Yue Yang, Youngki Park, David A Cassada, Daniel D Snow, Douglas G RogersAbstract:Abstract Blue-green algae (BGA) have been consumed as food and herbal medicine for centuries. However, safety for their consumption has not been well investigated. This study was undertaken to evaluate in vitro and in vivo toxicity of cultivated Nostoc Commune var. sphaeroides Kutzing (NO) and Spirulina platensis (SP). Neither NO nor SP contained detectable levels of microcystin (MC)-LA, MC-RR, MC-LW and MC-LR by LC/MS/MS. Cell viability remained ∼70–80% when HepG2 cells were incubated with 0–500 μg/ml of hexane, chloroform, methanol and water-extractable fractions of NO and SP. Four-week-old male and female C57BL/6J mice were fed an AIN-93G/M diet supplemented with 0%, 2.5% or 5% of NO and SP (wt/wt) for 6 months. For both genders, BGA-rich diets did not induce noticeable abnormality in weight gain and plasma alanine aminotransferase (ALT) and aspartate aminotransferase concentrations except a significant increase in plasma ALT levels by 2.5% NO supplementation in male mice at 6 month. Histopathological analysis of livers, however, indicated that BGA did not cause significant liver damage compared with controls. In conclusion, our results suggest that NO and SP are free of MC and the long-term dietary supplementation of up to 5% of the BGA may be consumed without evident toxic side-effects.
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hypocholesterolemic effect of Nostoc Commune var sphaeroides kutzing an edible blue green alga
European Journal of Nutrition, 2009Co-Authors: Heather E Rasmussen, Kara R Blobaum, Elliot D Jesch, Youngki Park, Timothy P Carr, Jiyoung LeeAbstract:Intake of an edible blue-green alga Nostoc Commune var. sphaeroides Kutzing (N. Commune) has been shown to lower plasma total cholesterol concentration, but the mechanisms behind the hypocholesterolemic effect have not been elucidated. To elucidate the mechanisms underlying the cholesterol-lowering effect of N. Commune in mice. Male C57BL/6J mice were fed the AIN-93 M diet supplemented with 0 or 5% (wt/wt) dried N. Commune for 4 weeks. Lipid levels in the plasma and liver, intestinal cholesterol absorption and fecal sterol excretion were measured. Expression of hepatic and intestinal genes involved in cholesterol metabolism was evaluated by quantitative realtime PCR. N. Commune supplementation significantly reduced total plasma cholesterol and triglyceride concentrations by ~ 20% compared to controls. Intestinal cholesterol absorption was significantly decreased, while fecal neutral sterol output was significantly increased in N. Commune-fed mice. mRNA levels of the cholesterol transporters such as Niemann Pick C1 Like 1, scavenger receptor class B type 1, ATP-binding cassette transporters G5 and A1 in small intestine were not significantly different between two groups. Hepatic lipid contents including total cholesterol, triglyceride and free cholesterol in N. Commune-fed mice were not significantly altered. However, the expression of cholesterol modulating genes including sterol regulatory element binding protein-2 and 3-hydroxy-3-methylglutaryl coenzyme A reductase were significantly increased in mice fed N. Commune. N. Commune supplementation exerted a hypocholesterolemic effect in mice, largely in part, by reducing intestinal cholesterol absorption and promoting fecal neutral sterol excretion.
Douglas G Rogers - One of the best experts on this subject based on the ideXlab platform.
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in vitro and in vivo safety assessment of edible blue green algae Nostoc Commune var sphaeroides kutzing and spirulina plantensis
Food and Chemical Toxicology, 2011Co-Authors: Yue Yang, Youngki Park, David A Cassada, Daniel D Snow, Douglas G RogersAbstract:Abstract Blue-green algae (BGA) have been consumed as food and herbal medicine for centuries. However, safety for their consumption has not been well investigated. This study was undertaken to evaluate in vitro and in vivo toxicity of cultivated Nostoc Commune var. sphaeroides Kutzing (NO) and Spirulina platensis (SP). Neither NO nor SP contained detectable levels of microcystin (MC)-LA, MC-RR, MC-LW and MC-LR by LC/MS/MS. Cell viability remained ∼70–80% when HepG2 cells were incubated with 0–500 μg/ml of hexane, chloroform, methanol and water-extractable fractions of NO and SP. Four-week-old male and female C57BL/6J mice were fed an AIN-93G/M diet supplemented with 0%, 2.5% or 5% of NO and SP (wt/wt) for 6 months. For both genders, BGA-rich diets did not induce noticeable abnormality in weight gain and plasma alanine aminotransferase (ALT) and aspartate aminotransferase concentrations except a significant increase in plasma ALT levels by 2.5% NO supplementation in male mice at 6 month. Histopathological analysis of livers, however, indicated that BGA did not cause significant liver damage compared with controls. In conclusion, our results suggest that NO and SP are free of MC and the long-term dietary supplementation of up to 5% of the BGA may be consumed without evident toxic side-effects.
