A fucose-containing, sulfated polysaccharide ascophyllan was isolated from the brown alga Ascophyllum nodosum. Composition analysis demonstrated that ascophyllan mainly contains uronic acid, xylose, fucose, and sulfate half ester in approximately equimolecular proportions, which are evidently distinct from those of alginate and fucoidan. Ascophyllan inhibited the proliferation of U937 cells in ...

Inspired by the remarkable adhesive capabilities to wet surfaces of the secretes of the brown alga Fucus serratus, novel glues have been designed and characterized. Formulations composed of phloroglucinol, alginate, and calcium ions are capable of adhering to a variety of surfaces. Rheological data show that the presence of phloroglucinol lowers the amount of Ca(2+) ions required for sol-gel tr...

Microcalorimetry was used to show that transition-temperature ranges of phospho- and glycolipids of the brown marine alga Laminaria japonica were similar (from -62 to -47 degrees C up to 62-65 degrees C), except for monogalactosyldiacylglycerol, the low-temperature limit of which was shifted to -78 degrees C. As was shown by polarizing microscopy, the low-enthalpy peaks at temperatures of appro...

A metagenomic library was constructed from microorganisms associated with the brown alga Ascophyllum nodosum. Functional screening of this library revealed 13 novel putative esterase loci and two glycoside hydrolase loci. Sequence and gene cluster analysis showed the wide diversity of the identified enzymes and gave an idea of the microbial populations present during the sample collection perio...

The functioning of carotenoids in photosynthesis is discussed in relation to the reaction mechanism. The energy transfer process from the allenic carotenoid, fucoxanthin, to chl a was intensively investigated in the newly isolated fucoxanthin-chl a / c protein assembly (FCPA) from a brown alga Dictyota dichotoma. The transfer time was shorter than 3 ps at 15°C. The energy level responsible for ...

Five glycerol derivatives (1-5) and three sterols (6-8) were isolated from the EtOH extraction of the brown alga of Sargassum parvivesiculosum. On the basis of spectroscopic methods, their structures were elucidated as 1,3-di-O-[2',2'-di-(p-phenylene) isopropylidene] glycerol (1), (2S)-1-O-heptatriacontanoyl glycerol (2), (2S)-1,2-di-O-palmitoyl-3-O-(6-sulpho-alpha-D-quinovopyranosyl) glycerol ...

Inducible resistance in plants is a defense strategy for avoiding the negative consequences of herbivory on plant fitness. Since resistance is costly, the induction of resistance may depend on resource availability. Resource-based plant–herbivore hypotheses predict that the cost of producing carbon-based defensive metabolites will be higher when an excess of nutrients is available for growth. W...

Three new diterpenes Amijiol acetate (3), dolabellane, Dolabellatrienol (4), and dolastane, Amijiol-7, 10-diacetate (9) were isolated together with the previously described Pachydictyol A (1), Isopachydictyol A (2), 8β-hydroxypachydictyol A (5), Amijiol (6), Isodictyohemiacetal (7) and Dictyol C (8) from the Red Sea brown alga Dictyota dichotoma var. implexa. The structures and relative stereoc...

Mineral composition of algal biomass from Fucus vesiculosus (the Baltic Sea, Estonia) is rich in light elements (Mg, K, Ca, Na) and halogens (Br, I). Arsenic content is also high (over 300 ppm); the content of other toxic elements (Hg, Sb, Se, etc.) is extremely low. Mineralization of the algal whole biomass does not depend on seasonal varieties. The content of α-L-guluronic acid residues, and ...

Four new plastoquinones, together with two known compounds, sargahydroquinoic acid and sargaquinoic acid, were isolated from the brown alga, Sargassum yezoense collected from the eastern coast of Korea. The structures of these compounds were elucidated based on spectroscopic analyses including NMR and MS. Their structures designated as meroterphenol A (1), B (2), C (3) and D (4) were characteri...