Svetlana V. Khotimchenko

Polar lipids and fatty acids of some marine macrophytes from the yellow sea

Polar lipid and fatty acid compositions of 26 species of marine macrophytes collected in the Yellow Sea during winter were determined. Each division of seaweeds and seagrasses have distinguishing lipid and fatty acid profiles which have a chemotaxonomic value for marine plants. Algal habitat conditions affect quantitative characteristics of the fatty acids but its influence was not the same for different species. The content of polyunsaturated fatty acids in Chinese algae, in comparison with the same or related species from other regions, was found to be noticeably higher for most of the algal species examined. Members of the genera Rhodomela, Gracilaria, Sargassum, Ulva, Enteromorpha (except E. linza) and Zostera had the same ratios of the principal fatty acids as those for related species from other regions. The draining period during low tides affected lipid content and ratio of polyunsaturated fatty acids in algae but it did not influence the polar lipid and fatty acid profiles.

Fatty acids of brown algae from the Russian far east

Abstract Twenty species of brown algae belonging to the Chordariales, Ralfsiales, Dictyosiphonales, Scytosiphonales, Desmarestiales, Laminariales and Fucales orders were investigated for their fatty acid composition by capillary gas chromatography. Polyunsaturated fatty acids (PUFAs) with 18 and 20 carbon atoms, palmitic and oleic acids were major components. No correlation between the taxonomic position of the brown algal species and the distribution of these acids was found. Peculiarities of fatty acid composition were shown for members of the Fucaceae only, which contained the highest percentages of 14:0 and 18:1(n–9), the lowest amounts of (n–3) PUFAs and had a C20 non-methylene interrupted acid. Agarum cribrosum had fatty acid patterns unique for the Phaeophyta. The occurrence of the rare C16 PUFAs, 18:2(n–4) and a high content of 22:5(n–3) were a characteristic feature of this alga. Fatty acid composition of brown algae depends on different factors and the extent of their influence is species-specific.

Response of prostaglandin content in the red alga Gracilaria verrucosa to season and solar irradiance

The influence of solar irradiance and seasons on prostaglandin (PG) and arachidonic acid (AA) content in the marine red alga Gracilaria verrucosa (Huds.) Papenf. (unattached form) was investigated. PGA(2), PGE(2), PGF(2), and 15-keto-PGE(2) were isolated from the alga, quantitatively analyzed as 4-methyl-7-methoxycoumarin esters by high-performance liquid chromatography, and their chemical structures were confirmed by 1H NMR. In June-September, the PG content in the alga was relatively stable (420 microg/g of dry wt. of PGE(2)+PGF(2); 40 microg/g of PGA(2)) and it increased 1.5 times in October. The highest level of PGs was detected in November (2500 microg/g of PGE(2)+PGF(2); 74 microg/g of PGA(2)) when water temperature was fairly low (5-10 degrees C). Algae grown for five months at 50% of incident photosynthetic active radiation (PAR(0)) contained two times less PGE(2) and PGF(2) than algae grown under natural conditions, but the amount of these PG in algae grown at 5% of PAR(0) was close to the normal level. On the contrary, when algae were grown at 5% of PAR(0) the content of PGA(2) increased up to 4 times compared to algae cultivated at 100% PAR(0). In June-November, the amount of AA in total algal lipids slightly varied from 48.9 to 56.7% and did not virtually depend on the light intensity. The probable reasons of the PG content variation in response to environmental factors are discussed.

Identification of diacylglycero-4′-O-(N,N,N-trimethyl)homoserine in mushrooms

An unusual polar lipid component was found in some mushrooms and was isolated fromBoletus edulis. It has been identified as diacylglycero-4′-O-(N,N,N-trimethyl)-homoserine (DGTS) by its thin-layer chromatography (TLC) mobilities and staining behavior as well as by means of infrared (IR) and nuclear magnetic resonance (1H NMR) spectroscopy and mass spectrometry. Identification of this lipid in mushrooms indicated that DGTS is widely distributed among a diverse group of lower plants and may have chemotaxonomic significance for fungi. It is interesting that DGTS is a component of some edible mushrooms commonly consumed in food.

Effect of solar irradiance on lipids of the green alga Ulva fenestrata Postels et Ruprecht

Abstract We examined variations in lipid composition of the marine green alga Ulva fenestrata grown under different irradiance conditions (80% of incident photosynthetically active radiation [PAR] and 24% PAR). The ratio of storage lipids (triacylglycerol) to major structural chloroplast lipids (glycolipids and phosphatidylglycerol) was influenced considerably by the irradiance. Triacylglycerol predominated in U. fenestrata exposed to 80% PAR (58.7±1.7% of total lipids). In contrast, when the alga was grown at 24% PAR, the amount of monogalactosyldiacylglycerol, sulfoquinovosyldiacylglycerol and phosphatidylglycerol increased two to three and a half times compared to algae cultivated at 80% PAR. The content of digalactosyldiacylglycerol and betaine lipid in U. fenestrata showed little dependence on light intensity. Each lipid class had a characteristic fatty acid composition. However, the relative proportions of fatty acids present in triacylglycerol, monogalactosyldiacylglycerol and sulfoquinovosyldiacylglycerol did not depend on irradiance conditions. The variation in fatty acid composition of digalactosyldiacylglycerol and phosphatidylglycerol and changes in the amounts of lipids were responsible for the differences in total fatty acid composition of U. fenestrata among light intensities. The most sensitive to the change in quantity of incident light were the 16:4n-3 and 16:0 acids. The highest level of 16:4n-3 acid was detected in algae grown under 24% PAR, whereas 16:0 acid was highest at 80% PAR. However, the total lipid content in the algae was relatively constant at different light intensities (5.0±1.0 mg/g fresh weight at 80% PAR and 5.2±1.1 mg/g at 24% PAR). These results suggest that changes in lipid composition of U. fenestrata can be considered as a mechanism of adaptation and survival of thalli subjected to variations in solar irradiance.

Variations in lipid composition among different developmental stages of Gracilaria verrucosa (Rhodophyta)

Abstract Variation in the lipid composition of the marine red alga Gracilaria verrucosa at different developmental stages was examined. Shoots, juveniles and mature tetrasporophytes, male and female gametophytes had similar qualitative lipid composition (glycolipids, phospholipids and neutral lipids). However, the ratio of these lipid groups and the content of individual lipid components depended on the developmental stage. Phospholipids were the main lipid group in shoots, due to the highest concentration of phosphatidylcholine. Glycolipids predominated in juvenile thalli as well as in tetrasporophytes, and male and female gametophytes. The content of storage lipids, i.e., triacylglycerols was 2–3 times lower in shoots and young algae compared to mature thalli. Comparison of these results with the literature on G. verrucosa thallus ultrastructure suggests that differences in lipid ratio are related to the formation and the structural alteration of cells or photosynthetic apparatus.

Distribution of diacylglycerotrimethylhomoserine and phosphatidylcholine in mushrooms

Abstract Fifty-eight species of mushrooms from different orders of Basidiomycetes were examined by HPTLC for the presence of 1,2-diacylglycero- O -4′-( N , N , N ,-trimethyl)homoserine(DGTS) and phosphatidylcholine (PC). It was found that DGTS was one of the main polar lipids in all species investigated from the orders Boletales and Hygrophorales. This lipid was detected as a minor component in a few species from Aphyllophorales and the family Tricholomataceae. The presence of DGTS does not depend on the stage of the development of fruit bodies and place of collection of these mushrooms. Phosphatidylcholine was the major phospholipid in all species investigated except for Leccinum scabrum, L. variocolar and Hygrophorus hypothejus in which this lipid was virtually absent. Possible biosynthetic mechanisms resulting in absence of PC are discussed.

Uncommon 16:1 (n-5) acid from Dictyota dichotoma and fatty acids of some brown algae of dictyotaceae

Abstract The detailed fatty acid composition of the brown algae, Dictyota dichotoma, Dictyopteris divaricata and Dictyota cervicornis are reported. About 35 fatty acids were identified, of which 16:0, 18:4 (n-3), 18:1(n-9), 14:0 and 20:4(n-6) predominated in each sample. A high content of an uncommon 16:1(n-5) and the occurrence of C 22 polyunsaturated fatty acids in minute amounts are characteristic features of algae from the genus Dictyota and Dictyopteris divaricata . The structure of 16:1(n-5) was confirmed by GC and mass spectrometry of its derivatives. The distribution of fatty acids among the polar lipids of Dictyota dichotoma are reported. The 16:1(n-5) acid was identified in glycolipids and betaine lipid.

Distribution of an amino acid-containing phospholipid in brown algae

The phospholipid composition of 30 species of brown algae belonging to eight different orders has been analysed by TLC. A new amino acid-containing phospholipid was detected in members of the orders, Ectocarpales, Chordariales, Dictyotales, Desmarestiales, Scytosiphonales, Laminariales and Fucales. The occurrence of this new amino acid-containing phospholipid has chemotaxonomic value for brown algae.