[Comprehensive study of the composition of fish fat extracts and quantitative criteria for distinguishing standardized omega-3 polyunsaturated fatty acids extracts].

Background Effects of drugs and biologically active supplements based on omega-3 polyunsaturated fatty acids (ω3 PUFA) considerably depend on the standardized content of eicosatetraenoic acid (EPA), docosahexaenoic acid (DHA), and other fatty acids in the extracts.Material and methods In this study, we comprehensively examined the composition of 10 ω3 PUFA samples with chromatographic measurement of more than 40 metabolites of fatty acids and other compounds. The data on extract composition were analyzed with current methods of intelligent data analysis (metric condensation method; multidimensional scaling; principal component analysis with axis identification; topology-metrical approach to recognition).Results Quantitative markers were obtained, which allowed separating the standardized ω3 PUFA-based samples (Omacor, Solgar omega-3 700, Femibion Natalker-2, Omega-3 concentrate, Omegamama) from less standardized ones (Fish oil-Teva, Omegatrin, Omeganol, etc.) based on results of a chromatographic analysis of fatty acid composition in the studied samples (EPA+DHA marker, ω6+ω11 marker, and standardization coefficient showing conformity of measured ω3 PUFA levels with the content stated by the manufacturer).Conclusions Among the studied samples, the pharmaceutical product Omacor showed the best values of standardization indexes.

Role of lipid components in formation and reactivation of Mycobacterium smegmatis "nonculturable" cells.

We have found that transition of actively dividing Mycobacterium smegmatis cells into the dormant "nonculturable" state is accompanied by increase in the protein/lipid ratio and disappearance of one of the main lipid components of the mycobacterial cells, trehalose monomycolate. In this case, oleic acid is accumulated in the culture medium due to its secretion by the mycobacterial cells. Addition of lipids of different classes to "nonculturable" M. smegmatis cells induces their resuscitation. The lipid reactivating effect is evidently caused by the presence of fatty acids in their composition, because free fatty acids also exhibited reactivation effect. Oleic acid in concentration of 0.05-3 µg/ml exhibited maximal effect, and that allows us to draw a conclusion concerning its signal role in the transition of dormant cells into active state.

The polar-lipid composition of the sphingolipid-producing bacterium Flectobacillus major.

Polar lipids comprise about 90% of the total chloroform-methanol extractable lipids of the Gram-negative, fresh-water, ring-forming bacterium Flectobacillus major FM and consist of at least 10 constituents. These are aminophosphosphingolipids, 2-N-(2'-D-hydroxy-13'-methyltetradecanoyl)-15-methyl-4(E)-hexad ecasph ingenyl-1-phosphoethanolamine (36.8% of the total polar lipids) and its 2'-deoxy derivative (3.7%); sulfonic-acid analogues of ceramide, 2-D-(2'-D-hydroxy-13'-methyltetradecanoyl)amino-3-D-hydroxy-15-met hyl hexadecane-1-sulfonic acid (18.1%) and its 2'-deoxy derivative (3. 5%); a lipoamino acid, N-[3-D-(15'-methylhexadecanoyloxy)-15-methylhexadecanoyl]-gl ycine (3. 7%); a lipodipeptide, N-¿N'-[3"-D-(15"'-methylhexadecanoyloxy)-15"-methylhexadecanoyl ]glycy l¿-L-serine (7.8%); 1,2-diacyl-sn-glycero-3-phosphoethanolamine (7. 7%), 1,2-diacyl-3-alpha-D-galactopyranosyl-sn-glycerol (2.9%); ceramide phospho-myo-inositol (4.9%), and a previously described unusual glycosphingolipid, 7-deoxy-7-amino-D-manno-heptulosonopyranosyl (1-hydroxycarbonyl-6-deoxy-6-amino-alpha-D-mannopyranosyl) ceramide (10.9%); the last two lipids contain only 15-methyl-4(E)-hexadecasphingenine as a long-chain base. The sole structural type of amide-bound fatty acids in the sphingolipids, including the sulfonic-acid analogues, is iso-15:0, either non-hydroxylated or hydroxylated at 2-C, whereas 15-methylhexadecanoic acid is the major ester-bound fatty acid in the remaining lipids.

A novel sulfonic-acid analogue of ceramide is the major extractable lipid of the gram-negative marine bacterium Cyclobacterium marinus WH.

The extractable lipids of the gram-negative, sea-water bacterium Cyclobacterium marinus strain WH contain about 94% of polar components which consist of two phospholipids, phosphatidylethanolamine (29% of the total lipids) and phosphatidylcholine (7%), and two phosphorus-free lipids. One of the latter has been shown to be a novel sulfonic-acid analogue of ceramide, 2-D-(2'-D-hydroxy-13'-methyltetradecanoyl) amino-3-D-hydroxy-15-methylhexadec-4 (E)-en-1-sulfonic acid (48%), and other is a lipodipeptide, N-[3-d-(13'-methyltetradecanoyloxy)-15-methylhexadecanoyl] glycyl-L-serine (11%), which has so far been found only in a Flavobacterium sp. strain. The dominant fatty acid residues of the phospholipids are iso-15:0, n-16:0, 16:1 and 18:1, the acyl residues linked to the sn-1 carbon of the glycerol moiety being somewhat more saturated as compared with those located at the sn-2 position. A new procedure for determination of the absolute configuration of 2- and 3-hydroxy fatty acids is briefly described.

Unusual lipid composition of the gram-negative, freshwater, stalked bacterium Caulobacter bacteroides NP-105.

The extractable lipids of the gram-negative, stalked, freshwater bacterium Caulobacter bacteroides NP-105 account for about 9.5% by weight of dry cells, polar lipids comprising up to 95% of the total. The polar lipids consist of five glycolipids, namely, 1,2-diacyl-3-alpha-D-glucopyranosyl-sn-glycerol (I) (34% of the total), 1,2-diacyl-3-alpha-D-[6'-(1",2"-diacyl-sn-glycero-3-phospho)]glucopyranosyl-sn-glycerol (II) (7%), 1,2-diacyl-3-a-D-glucuronopyranosyl-sn-glycerol (III) (17%), 1,2-diacyl-3-alpha-D-(6'-sulfo)quinovopyranosyl-sn-glycerol (V) (9%), and 1,2-diacyl-3-alpha-D-[4'-(alpha-D-glucopyranosyl)] glucuronopyranosyl-sn-glycerol (VI) (28%), and one glycerophospholipid, 1,2-diacyl-sn-glycero-3-phosphoglycerol (IV) (5%). The main fatty acyls of the lipids are n-16:0, cis-18:1 omega7, and cis-11,12-methyleneoctadecanoic (lactobacillic) acid residue. Of the 6 lipids listed, only 3 (I, IV, and V) can be treated as widely encountered. However, sulfonic glycolipid V is a characteristic lipid component of photosynthetic organisms rather than non-photosynthetic ones. Phosphatidyl derivatives of glycosyldiacylglycerols of type II normally occur in gram-positive bacteria, among gram-negative bacteria they have been revealed only in two species of the Pseudomonas genus. Glucuronosyl and alpha-glucosyl-a-glucuronosyl diacylglycerols such as III and VI, respectively, are very rare lipids, the latter being found so far only in a Streptomyces strain.