The Experts below are selected from a list of 132 Experts worldwide ranked by ideXlab platform
Eric Deslandes - One of the best experts on this subject based on the ideXlab platform.
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Isethionic Acid and floridoside isolated from the red alga grateloupia turuturu inhibit settlement of balanus amphitrite cyprid larvae
Biofouling, 2004Co-Authors: Claire Hellio, Christelle Simoncolin, Anthony S Clare, Eric DeslandesAbstract:Isethionic Acid (2-hydroxyethane sulfonic Acid) and floridoside (2-O-α-D-galactopyranosylglycerol) were extracted from the red alga, Grateloupia turuturu, and tested for anti-settlement activity against cyprid larvae of the tropical barnacle, Balanus amphitrite and for their toxicity to nauplius larvae. Isethionic Acid was active for anti-settlement but had the disadvantage of being toxic to nauplius larvae. Floridoside was a potent inhibitor of cyprid settlement at non-toxic concentrations to nauplii (0.01 mg ml−1).
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NMR 13C-isotopic enrichment experiments to study carbon-partitioning into organic solutes in the red alga Grateloupia doryphora
Plant Physiology and Biochemistry, 2004Co-Authors: Christelle Simon-colin, Roger Pichon, Nelly Kervarec, Eric DeslandesAbstract:Abstract The red alga Grateloupia doryphora Montagne (Howe) (Cryptonemiales, Halymeniaceae) was used as a model to investigate the effects of changes in seawater salinity on the intracellular low-molecular-weight organic compounds. Carbon-partitioning into major organic solutes was followed by 13 C nuclear magnetic resonance (NMR) spectroscopy on living algae incubated in NaH 13 CO 3 -enriched seawater, and by high resolution 1 H and 13 C NMR experiments performed on 13 C-enriched algal extracts. NMR and high performance liquid chromatography (HPLC) analyses both demonstrated that floridoside level was the most affected by changes in salinity: it rose under the hypersaline treatment and decreased under hyposaline one. Moreover, at low salinity, the high labeling of floridoside (45.3% 13 C-enrichment for C1) together with its low concentrations both provided evidence of great increase in the de novo biosynthesis and turnover rate. Our experiments also demonstrated a high incorporation of photosynthetic carbon into amino Acids, especially glutamate, under hypoosmotic conditions. On the other hand, Isethionic Acid and N -methyl-methionine sulfoxide were only partly labeled, which indicates they do not directly derive from carbon photoassimilation. In algae exposed to high salinity, elevated concentrations of floridoside coupled to a low labeling (9.4%) were observed. These results suggest that hyperosmotic conditions stimulated floridoside biosynthesis from endogen storage products rather than from carbon assimilation through photosynthesis.
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characterization of n methyl l methionine sulfoxide and Isethionic Acid from the red alga grateloupia doryphora
Phycological Research, 2002Co-Authors: Christelle Simoncolin, Nelly Kervarec, Roger Pichon, Marieanne Bessieres, Eric DeslandesAbstract:SUMMARY Isethionic Acid (2-hydroxyethane sulfonic Acid) and N-methyl-L-methionine sulfoxide (4-methane sulfinyl-2-methylamino butyric Acid) were isolated from the red alga Grateloupia doryphora (Cryptonemiales) collected from Brittany (France); they were identified as major organic solutes together with floridoside (α-D-galacto-pyranosyl-(1–2)-glycerol). The presence of Isethionic Acid has recently been reported in certain red algae, however, the occurrence of N-methyl-L-methionine sulfoxide is still very rare. This report deals with the first isolation of Isethionic Acid and N-methyl-L-methionine sulfoxide from G. doryphora and their subsequent NMR characterization.
Sunghoon Park - One of the best experts on this subject based on the ideXlab platform.
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The effects of betonicine, floridoside, and Isethionic Acid from the red alga Ahnfeltiopsis flabelliformis on quorum-sensing activity
Biotechnology and Bioprocess Engineering, 2008Co-Authors: Sunghoon ParkAbstract:A mixture of three compounds (betonicine, floridoside, and Isethionic Acid) purified from the red alga Ahnfeltiopsis flabelliformis , was reported to have an inhibition activity on bacterial quorum sensing mechanism mediated by Noctanoyl- dl -homoserine lactone (OHL) and the TraR transcriptional activator protein. We subsequently conducted a more detailed investigation of the three compounds using chemically synthesized (betonicine and floridoside) or commercially available (Isethionic Acid) compounds, individually or in various combinations. When tested alone, none of the three compounds inhibited OHL, but a mixture of floridoside and Isethionic Acid exhibited a dose-dependent inhibitory effect on the function of OHL. In contrast, betonicine or its isomer exhibited a dose-dependent stimulatory effect, similar to OHL, at concentrations between 10^−3 and 10^−6 M. These three compounds will be useful for elucidating the interaction between OHL and TraR, and for developing novel bacterial quorum-sensing inhibitors.
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Quorum sensing inhibitors from the red alga,Ahnfeltiopsis flabelliformis
Biotechnology and Bioprocess Engineering, 2007Co-Authors: Sunghoon ParkAbstract:Three new acylhomoserine lactone (AHL) inhibitors have been isolated from the Korean red alga. Ahnfeltiopsis flabelliformis , via bioactivity-guided fractionation using the recombinant Agrobacterium tumefaciens liquid culture bioassay. Unlike the majority of AHL inhibitors reported to date, these compounds were α- d -galactopyranosyl-(1→2)-glycerol (floridoside) (1), betonicine (2), and Isethionic Acid (3), all of which are structurally unrelated to AHLs.
Christelle Simoncolin - One of the best experts on this subject based on the ideXlab platform.
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Isethionic Acid and floridoside isolated from the red alga grateloupia turuturu inhibit settlement of balanus amphitrite cyprid larvae
Biofouling, 2004Co-Authors: Claire Hellio, Christelle Simoncolin, Anthony S Clare, Eric DeslandesAbstract:Isethionic Acid (2-hydroxyethane sulfonic Acid) and floridoside (2-O-α-D-galactopyranosylglycerol) were extracted from the red alga, Grateloupia turuturu, and tested for anti-settlement activity against cyprid larvae of the tropical barnacle, Balanus amphitrite and for their toxicity to nauplius larvae. Isethionic Acid was active for anti-settlement but had the disadvantage of being toxic to nauplius larvae. Floridoside was a potent inhibitor of cyprid settlement at non-toxic concentrations to nauplii (0.01 mg ml−1).
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characterization of n methyl l methionine sulfoxide and Isethionic Acid from the red alga grateloupia doryphora
Phycological Research, 2002Co-Authors: Christelle Simoncolin, Nelly Kervarec, Roger Pichon, Marieanne Bessieres, Eric DeslandesAbstract:SUMMARY Isethionic Acid (2-hydroxyethane sulfonic Acid) and N-methyl-L-methionine sulfoxide (4-methane sulfinyl-2-methylamino butyric Acid) were isolated from the red alga Grateloupia doryphora (Cryptonemiales) collected from Brittany (France); they were identified as major organic solutes together with floridoside (α-D-galacto-pyranosyl-(1–2)-glycerol). The presence of Isethionic Acid has recently been reported in certain red algae, however, the occurrence of N-methyl-L-methionine sulfoxide is still very rare. This report deals with the first isolation of Isethionic Acid and N-methyl-L-methionine sulfoxide from G. doryphora and their subsequent NMR characterization.
A. Singh - One of the best experts on this subject based on the ideXlab platform.
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Isethionate in certain red algae
Journal of Applied Phycology, 1994Co-Authors: P. B. Holst, K. S. Bisht, D. B. Sahoo, V.s. Parmar, Uffe Anthoni, S.e. Nielsen, P H Nielsen, Carsten Christophersen, S. Gupta, A. SinghAbstract:Isethionic Acid (2-hydroxyethanesulfonic Acid) was isolated as salts from a methanolic extract of Hypnea musciformis collected in the Indian Ocean and identified by comparison (nuclear magnetic resonance, infrared and mass spectrometry) with an authentic sample. The compound has not previously been reported from plants. Investigations of 13 other species of red algae showed that only some samples of species of the families Gigartinaceae, Hypnaceae and Solieriaceae (all of order Gigartinales) contained isethionates.
Claire Hellio - One of the best experts on this subject based on the ideXlab platform.
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Isethionic Acid and floridoside isolated from the red alga grateloupia turuturu inhibit settlement of balanus amphitrite cyprid larvae
Biofouling, 2004Co-Authors: Claire Hellio, Christelle Simoncolin, Anthony S Clare, Eric DeslandesAbstract:Isethionic Acid (2-hydroxyethane sulfonic Acid) and floridoside (2-O-α-D-galactopyranosylglycerol) were extracted from the red alga, Grateloupia turuturu, and tested for anti-settlement activity against cyprid larvae of the tropical barnacle, Balanus amphitrite and for their toxicity to nauplius larvae. Isethionic Acid was active for anti-settlement but had the disadvantage of being toxic to nauplius larvae. Floridoside was a potent inhibitor of cyprid settlement at non-toxic concentrations to nauplii (0.01 mg ml−1).
