The fatty acid composition of a Vibrio alginolyticus associated with the alga Cladophora coelothrix. Identification of the novel 9-methyl-10-hexadecenoic acid.

The fatty acid composition of a new strain of Vibrio alginolyticus, found in the alga Cladophora coelothrix, was studied. Among 38 different fatty acids, a new fatty acid, 9-methyl-10-hexadecenoic acid and the unusual 11-methyl-12-octadecenoic acid, were identified. Linear alkylbenzene fatty acids, such as 10-phenyldecanoic acid, 12-phenyldodecanoic acid and 14-phenyltetradecanoic acid, were also found in V. alginolyticus. The alga contained 43% saturated fatty acids, and 28% C16-C20 polyunsaturated fatty acids of the n-3 and n-6 families.

Antiinfluenza virus effect of extracts from marine algae and invertebrates.

Sixty products, derived from marine organisms, typical of the Bulgarian Black Sea coast, were examined for inhibitory activity on the reproduction of influenza viruses in tissue cultures. The antiviral effect was investigated by the reduction of virus infectivity. Using representative strains of influenza virus it was shown that apparently the inhibitory effect was strain-specific. The most effective products were further studied in fertile hen's eggs and in experimental influenza infection in white mice.

Chemical composition and biological activities of the Black Sea algae Polysiphonia denudata (Dillw.) Kutz. and Polysiphonia denudata f. fragilis (Sperk) Woronich.

The two investigated algae had almost identical sterol composition, but there were significant differences in the composition of the polar components and especially in the composition of the volatiles. P. denudata f. fragilis extracts possessed a stronger biological activity (antibacterial, antifungal and toxicity against Artemia salina). Despite the minute morphological differences between the two algae, we recommend P. denudata f. fragilis to be regarded as P. denudata subsp. fragilis.

[Polar components of Black sea seaweed Colpomenia peregrina (Sauv.) Hamel]. / Poliarnye komonenty chernomorskoi buroi vodorosli Colpomenia peregrina (Sauv.) Hamel.

GC-MS of trimethylsilyl derivatives of the compounds present in the butanolic extract of biomass of brown seaweed Colpomenia peregrina from the Black Sea aided in identification of 24 components, including aliphatic hydroxy and keto and aromatic acids, glycerol, mannitol, floridoside, and monosaccharides. The polysaccharide composition of the biomass was also studied, with high sodium alginate and laminaran contents and a comparatively low level of fucoidan being revealed. The polysaccharides were isolated from the biomass by fractional extraction and purified by precipitation or ion exchange chromatography. The structures of alginic acid and laminaran were deduced from 13C NMR spectra and confirmed, in the case of laminaran, by methylation analysis. The sodium alginate was shown to contain more guluronic (G) than mannuronic acid (M) residues, the M/G ratio being 0.48. Laminaran was demonstrated to be a beta-glucan with 1-->3 linkages in its backbone and 1-->6 linkages in its branching points, which is characteristic of brown algae. Fucoidan turned out to be a complex heteropolysaccharide containing, in addition to fucose and sulfate, other neutral monosaccharides and uronic acids. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 2; see also http://www.maik.ru