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Procedures for preparing 4,4-dimethyloxazoline (DMOX) and pyrrolidine derivatives from fatty acid methyl esters (FAMEs) were modified to provide milder and simpler conditions for the derivatization reactions widely used in the mass spectrometric analysis of fatty acids. DMOX and pyrrolidine derivatives were obtained overnight at room temperature in the presence of sodium borohydride. The proposed method, involving a low-temperature condensation-cyclization of FAME to DMOX, allows for the direct preparation of DMOX derivatives from non-hydroxy, 2- and 3-hydroxy acid methyl esters. The described simple one-pot procedures are “mild” alternatives to existing methods, which require the use of elevated temperatures.

Young fronds of ferns are consumed as a vegetable in many countries. The aim of this study was to analyze three fern species that are available for sale in the Russian Far East as dietary sources in terms of fatty acids that are important for human physiology: arachidonic acid (20:4n-6, ARA), eicosapentaenoic acid (20:5n-3, EPA) and other valuable long-chain polyunsaturated fatty acids. The content of ARA and EPA was 5.5 and 0.5 mg/g dry weight, respectively, in Pteridium aquilinum, 4.1 and 1.1 in Matteuccia struthiopteris, and 2.2 and 0.8 in Osmundastrum asiaticum. Salted fronds of P. aquilinum contained less these fatty acids than the raw fronds, with a decrease of up to 49% for ARA and 65% for EPA. These losses were less pronounced or even insignificant in dried fronds. Cooked ferns preserved significant portions of the long-chain polyunsaturated fatty acids: cooked P. aquilinum contained 4.4 mg/g dry weight ARA and 0.3 mg/g dry weight EPA. The ferns may provide a supplemental dietary source of these valuable long-chain polyunsaturated fatty acids, especially for vegetarian diets.

Fatty acids (FA) of two species of abyssal Echinodermata-the sea star (Asteroidea) Eremicaster vicinus and the sea urchin (Echinoidea) Kamptosoma abyssale-from the Kuril-Kamchatka Trench, collected at depths of 5210 and 6183 m, were analyzed. Lipids of these deposit-feeding animals showed similar FA compositions: 20.05-16.08% saturated, 42.20-39.50% monoenoic, and 37.75-44.42% polyunsaturated FA, respectively. The contents of odd- and branched-chain FA were 17.35% and 8.80%, respectively. A significant part of FA was represented by uncommon FA such as 21:4(n-7), 22:4(n-8), 22:5(n-5), and 23:4(n-9), earlier discovered in deep-sea foraminifera. Also, the newly found acid, related to the ω2 family, Δ5,8,11,14,17,20-22:6(n-2), amounted 1.60% and 0.33% of total FA, respectively, for the two species. Such unusual FA composition of these abyssal species can be explained by the transfer and modification of FA from consumed foraminifera, which in turn, feed on bacteria.

The lipid content and fatty acid (FA) composition of seeds from the Asian ginseng Panax ginseng growing naturally in taiga forests of the Russian Far East and seeds from cultivated ginseng were studied in this work. The total lipid content of seeds from both wild and cultivated plants was 9–12 % of fresh weight. FA were analyzed as isopropyl esters on a polar capillary column BD-225, which allows good separation of petroselinic and oleic acids. The structure of FAs was confirmed using GC–MS of fatty acid methyl ester (FAME) and 4,4-dimethyloxazoline derivatives. In all the seed samples, the major FA was petroselinic acid 18:1(n-12) which comprised more than 60 %; the contents of oleic and linoleic acids were lower (15–17 and 15–16 %, respectively). Earlier, a higher level (>80 %) of oleic acid had been reported for ginseng seeds. This discrepancy can be explained by an insufficient separation of these acids on standard columns used for GC of FAME. In general, seeds of wild and cultivated ginseng are very similar in lipid content and FA composition.

Ferns are known to contain long chain polyunsaturated fatty acids which may provide health benefits. The objective of this study was to investigate ferns of Pacific temperate regions (Far East of Russia and New Zealand) as sources of valuable fatty acids: arachidonic (20:4n-6) and eicosapentaenoic (20:5n-3). Fatty acids were analyzed in fronds of 23 fern species from 12 families. Major fatty acids include: 18:3n-3 (6-68% of total fatty acids), 16:0 (6-33%), 18:2n-6 (5-46%), 18:1n-9 (1-60%), 20:4n-6 (1-16%). Polyunsaturated fatty acids of fern fronds belong to the omega-6 (16:2n-6, 18:2n-6, 18:3n-6, 20:2n-6, 20:3n-6, 20:4n-6) and omega-3 (16:3n-3, 18:3n-3, 18:4n-3, 20:3n-3, 20:4n-3, 20:5n-3) families. For the first time, Δ5-unsaturated polymethylene-interrupted fatty acids were reported for ferns: sciadonic (5,11,14-20:3) and juniperonic (5,11,14,17-20:4) acids (up to 1.9% and 0.4%, respectively). Fatty acid profiles in fern fronds were unrelated to fern taxonomy, but affected by spore presence: fronds with sporangia/spores contained more 18:1n-9 and/or 18:2n-6. The absolute content of 20:4n-6 was found to be relatively constant for a species in different seasons. 20:5n-3 was a minor fatty acid (traces-5%) which accumulates during the vegetation period. Young fronds of the New Zealand ferns Phymatosorus pustulatus and Pteridium esculentum were enriched in 20:4n-6, while aged fronds of Cyathea dealbata had the highest level of 20:5n-3. The mature fronds of the Far Eastern ferns Phegopteris connectilis, Dryopteris expansa, and Athyrium sinense were also enriched in 20:5n-3.

The soft corals of the genus Xenia are common for Indo-Pacific reef ecosystems. Lipid class, fatty acid (FA), phospho- and phosphonolipid molecular species compositions were identified for the first time in the soft coral Xenia sp. from Vietnam. Total lipids consisted predominantly of waxes, monoalkyl diacylglycerols, triacylglycerols, sterols, and polar lipids (21.4, 7.7, 14.2, 10.5, and 36.7 %, respectively). Sesquiterpene alcohol, valerenenol, was found. Acids 16:0, 18:3n-6, 20:4n-6, and 20:5n-3 dominated in total FA. The markers of zooxanthellae (18:4n-3 and 18:5n-3) and octocorals (24:5n-6 and 24:6n-3) were detected. Acids 18:5n-3, 20:4n-6, 22:4n-6, and 24:5n-6 concentrated in FA of polar lipids, whereas 14:0, 16:0, 16:1n-7, 18:2n-6, and 18:3n-6 were the major FA of neutral lipids. ChoGpl, EtnGpl, SerGpl, CAEP, PtdIns, and lyso ChoGpl constituted 39.5, 20.8, 20.5, 9.7, 4.3, and 5.3 %, respectively, of the sum of phospho- and phosphonolipids. Thirty-two molecular species of phospholipids and ceramide aminoethylphosphonate (CAEP) were determined by high resolution tandem mass spectrometry. Lyso 18:0e PakCho (4.1 %), 18:0e/20:4 PakCho (20.5 %), 18:1e/20:4 PlsEtn (18.0 %), 18:0e/24:5 PakSer (14.0 %), and 16:0 CAEP (9.6 %) were the major molecular species. EtnGpl and PtdIns mainly consisted of alkenyl acyl and diacyl forms, respectively. Alkyl acyl forms predominated in ChoGpl and SerGpl. Acid 24:5n-6 was a principal FA in SerGpl, whereas 20:4n-6 was more abundant in ChoGpl and EtnGpl. PtdIns contained various C20-24 PUFA. In the context of chemotaxonomy of corals, Xenia sp. has the lipid composition typical for soft corals and the FA profile similar to that of alcyonarians with the high level of 18:3n-6.

Fatty acids (FA) of agglutinating foraminifera of two genera, Bathysiphon and Rhabdammina, collected from a depth of 3307-3377 m in the Kuril Basin, Sea of Okhotsk, and adjacent deep-sea waters of the Pacific Ocean, were analyzed. In lipids of two Bathysiphon species, in addition to common FA typical for marine organisms, the uncommon ∆4 and ∆7 monoenoic acids and ∆4,7-dienoic acid were found in noticeable amounts. FA of two Rhabdammina species included also such uncommon acids as ∆5,8,11,14-21:4, ∆5,8,11,14-22:4, and ∆5,8,11,14-23:4, which are homologues to arachidonic acid. High levels of cis-vaccenic and arachidonic acids were typical for lipids of all the studied species. At the same time, we observed a substantial difference in FA composition between members of these two genera. Using GC and GC-MS of FAME, pyrrolidide and DMOX derivatives, the structures of 10 new FA were confirmed: ∆4-i-16:1 (1.1-0.6%), ∆7-i-21:1 (0.4%), ∆7-ai-21:1 (0.3-0.8%), ∆4,11-18:2 (0.3-0.9%), ∆4,7-20:2 (8.8%), ∆7,12-20:2 (0.4-0.6%), ∆4,7-21:2 (0.6%), ∆7,12-22:2 (6.4-2.1%); ∆5,8,11,14-22:4 (1.2-2.0%), and ∆5,8,11,14-23:4 (1.7-2.3%). The origin of the new FA and the role of foraminifera FA in deep-sea communities are discussed.

The taxonomic study of two Gram-negative, aerobic, non-pigmented bacteria KMM 9010(T) and KMM 9023(T) isolated from a sandy sediment sample collected from the Sea of Japan seashore was performed. On the basis of the nearly complete 16S rRNA gene sequences, strains KMM 9010(T) and KMM 9023(T) clustered with the Roseobacter lineage (class Alphaproteobacteria) forming a distinct phylogenetic line adjacent to the genus Donghicola. Novel strains shared the highest sequence similarity of 96.4% to each other and lower than 96.1% similarities to other validly named genera of the class Alphaproteobacteria. In both strains, ubiquinone Q-10 was found to be the major respiratory quinone; phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidic acid, and an unknown aminolipid were the major polar lipids and C(18:1)ω7c and 11-methyl C(18:1)ω7c were predominant fatty acids. The DNA G+C content was 60.5 mol% (KMM 9010(T)) and 65.4 mol% (KMM 9023(T)). Based on phenotypic properties and phylogenetic evidence, strains KMM 9010(T) and KMM 9023(T) should be classified as two novel species in a new genus, Poseidonocella gen. nov., with Poseidonocella pacifica sp. nov., the type species with the type strain KMM 9010(T) (= NRIC 0794(T) = JCM 17310(T)), and Poseidonocella sedimentorum sp. nov. as the second species with the type strain KMM 9023(T) (= NRIC 0796(T) = JCM 17311(T)).

Two Gram-negative, aerobic, non-pigmented, non-motile, rod-shaped bacteria, strains KMM 9015 and KMM 9018T, were isolated from a sample of shallow sediment collected from the Sea of Japan. An analysis of the nearly complete 16S rRNA gene sequences showed that the isolates were very close to each other phylogenetically (99.9 % sequence similarity) and their close relatives wereMarinovum algicolaFF3T(95.8 and 95.9 %, respectively) and members of the generaLeisingera(95.7–95.1 and 95.8–95.2 %),Phaeobacter(95.0–94.2 and 95.1–94.2 %) andThalassobius(96.3–94.8 and 96.2–94.7 %) of the classAlphaproteobacteria. In phylogenetic trees based on 16S rRNA gene sequences, strains KMM 9015 and KMM 9018Twere positioned as a distinct phylogenetic line adjacent toMarinovum algicola. The major isoprenoid quinone was Q-10, the polar lipids consisted of phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unknown lipid and the major fatty acid was C18 : 1ω7c, followed by 11-methyl C18 : 1ω7c, in both strains. The DNA G+C contents of strains KMM 9015 and KMM 9018Twere 60.2 and 61.9 mol%, respectively. Based on distinctive phenotypic characteristics and phylogenetic analysis, strains KMM 9015 and KMM 9018Trepresent a novel species in a novel genus, for which the namePrimorskyibacter sedentariusgen. nov., sp. nov. is proposed. The type strain ofPrimorskyibacter sedentariusis strain KMM 9018T( = NRIC 0784T = JCM 16874T).

Analyses of lipids and fatty acids in muscles and hepatopancreas of five commercially exploited crabs inhabiting the Sea of Japan and the Okhotsk Sea, namely Paralithodes camtschaticus , Paralithodes platypus , Chionoecetes opilio, Chionoecetes angulatus and Chionoecetes japonicus , have been carried out. The total lipid level (TL) in muscles ranged from 0.53% of wet weight (ww) to 1.57% of ww and the amount of phospholipids exceeded that of triglycerides. The TL contents in the hepatopancreas of all crabs were higher than in muscles and varied between 10.2% ww in C. angulatus and 19.8% ww in P. platypus , the major class of lipids being triglycerides. The main polar lipids in the hepatopancreas and muscles were phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Among polyunsaturated fatty acids (PUFAs), the n -3 fatty acids have dominated; 16:0, 18:1 n -9, 20:5 n -3 and 22:6 n -3 were the main fatty acids contained in the tissues studied. In all the crabs, excluding C. angulatus , the PUFAs n -3/ n -6 ratio in muscles varied between 7.02 and 10.3 while, in the hepatopancreas, the ratio varied between 4.00 and 6.62.

New cerebrosides containing N-acetylglucosamine were isolated from the marine sponge Oceanapia sp. Some of them contain n-and iso-C18-and iso-C19-phytosphingosines N-acylated by n-C16:0, n-C17:0, and n-C18:0 fatty acids, some other are derivatives of iso-and anteiso-C17-,-C18-, and-C19-phytosphingosines N-acylated by long-chain (C24-C28) α-hydroxy acids. The structures of these compounds were determined by NMR spectroscopy, MALDI-TOF mass spectrometry, and by chemical transformations.

Significant amounts of polyunsaturated fatty acids (PUFA) with a chain length of 26 carbon atoms were detected in lipids of five deep water species of Ophiuroidea besides common fatty acids with chain lengths between 14 and 24. By means of hydrogenation, GC–MS of the methyl esters, and 4,4-dimethyloxazoline (DMOX) derivatives of these C26 acids were characterized as 5,8,11,14,17,20,23-hexacosaheptaenoic [26:7(n-3)]; 8,11,14,17,20,23-hexacosahexaenoic [26:6(n-3)]; 5,8,11,14,17,20- hexacosahexaenoic [26:6(n-6)]; and 11,14,17,20,23-hexacosapentaenoic [26:5(n-3)]. Concentrations of these acids varied from 0.3 to 4.5 mol% of the total FA. In all the samples investigated, the main component of C26PUFA was hexacosaheptaenoic acid 26:7(n-3). These C26PUFA are localized mainly in polar lipids. The presence of the possible biosynthesis precursors suggests that the C26PUFA are produced by the brittle stars, and are not accumulated from food sources. This finding can also explain the presence of small amounts of the 26:7(n-3) acid detected earlier in flesh lipids of the roughscale sole Clidoderma asperrimum, which feeds on deep water brittle stars. We suggest a possible scheme of the biosynthesis of C26 PUFA.

During gas chromatography (GC) analysis of fatty acid (FA) composition of the dinoflagellate Gymnodinium kowalevskii, we found unex-pectedly low and irreproducible content of all-cis-3,6,9,12,15-octadecapentaenoic acid (18:5n-3), which is an important chemotaxonomic marker of several classes of microalgae. We compared chromatographic behavior of 18:5n-3 methyl ester and other GC derivatives obtained using different conventional methods of derivatization. The use of methods based on saponification or base-catalyzed transesterification resulted in a mixture of double-bond positional isomers of 18:5. On a SUPELCOWAX 10 column, the equivalent chain length (ECL) value for authentic 18:5n-3 methyl ester was 20.22, whereas the main component after base-catalyzed methylation had ECL 20.88. Attempts to prepare N-acyl pyrrolidides or 4,4-dimethyloxazoline (DMOX) derivatives of 18:5n-3 also gave inadequate results. These derivatives also showed a main peak corresponding to isomerized 18:5. Mass spectra for both DMOX and pyrrolidide derivatives of this compound showed the base peak at m/z 139, probably corresponding to 2,6,9,12,15-18:5 acid. Of all methods tested for methylation, only derivatization with 5% HCl or 1% sulphuric acid in methanol gave satisfactory results. Therefore, GC or GC-mass spectrometry analyses of algal lipids containing 18:5n-3 may be inaccurate when base-catalyzed methods of FA derivatization are applied. The best and simplest way to avoid incorrect GC results is to use standard acid-catalyzed methylation.

A mild and convenient method has been developed for preparing 4,4-dimethyloxazoline (DMOX) derivatives of fatty acids for GC-MS analysis. First, fatty acid methyl esters are converted to corresponding amides by incubation overnight at room temperature with 2-amino-2-methyl-1-propanol and a catalytic amount of sodium methoxide. The resulting 2-(methylpropanol) amides were isolated by partition between hexane-diethyl ether and water, and then converted to 4,4-dimethyloxazoline derivatives by treatment with trifluoroacetic anhydride under mild conditions (50 °C for 45 min). Structures of 2-methylpropanol amide and a DMOX derivative of oleic acid were confirmed by GC-MS. This method was applied to different FAME prepared from animal, plant or microbial lipids. The suggested method is most suitable for structure analysis of polyunsaturated fatty acids (PUFA) and for acids with double bonds in close to terminal positions. Application of the method is illustrated with spectra of the DMOX derivatives of 16:1(n-13), 24:5(n-6) and 24:6(n-3) acids.

A taxonomic study of three aerobic, Gram-negative, non-pigmented, non-motile rod-shaped bacterial strains, designated KMM 9008, KMM 9017, and KMM 9024T, which were isolated from a sandy sediment sample collected from the Sea of Japan seashore, was undertaken. The DNA–DNA hybridization values of 88–96% obtained between novel strains confirm their assignment to the same species. An analysis of the nearly complete 16S rRNA gene sequences showed that the novel isolates were closely related to each other (99.6–100% sequence similarity) and shared highest sequence similarities to the described genera Celeribacter (96.2–95.9%), Pseudoruegeria (95.6–94.3%), and Thalassobacter (95.2–93.1%) within the class Alphaproteobacteria. The major isoprenoid quinone was Q-10, polar lipids were phosphatidylcholine, phosphatidylglycerol, phosphatidic acid, an unknown aminolipid and an unknown lipid as prevalent, and phosphatidylethanolamine was a minor component, and major fatty acids were C18:1 ω7c , followed by 11-Methyl C18:1 ω7c, C12:1 and C10:0 3-OH in all strains. The DNA G+C content of strains KMM 9008, KMM 9017, and KMM 9024T was in the range of 56.7–60 mol%. Based on distinctive phenotypic characteristics and phylogenetic distance, strain KMM 9024T (=NRIC 0787T = JCM 17190T) represents the type strain of a novel species in a novel genus, for which the name Vadicella arenosi gen. nov., sp. nov. is proposed.

An aerobic, Gram-stain-negative, non-pigmented, non-motile bacterium, strain KMM 9031T, was isolated from a sandy sediment sample collected from the shore of the Sea of Japan and subjected to phenotypic and phylogenetic analysis. Based on comparative 16S rRNA gene sequence analysis, strain KMM 9031Tconstituted a separate phylogenetic line within theRoseobacterclade of the classAlphaproteobacteria, sharing highest sequence similarities with members of the generaRoseovarius(92.7–95.3 %),Pseudoruegeria(94.5 %),Sulfitobacter(92.7–94.4 %) andThalassobacter(94.2–94.3 %). The predominant fatty acid of strain KMM 9031Twas C18 : 1ω7c, with C16 : 0, C10 : 03-OH and C12 : 13-OH present in lesser amounts. The DNA G+C content of the isolate was 52.6 mol%. The major isoprenoid quinone was Q-10 and polar lipids comprised phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol and two unknown lipids. On the basis of phylogenetic analysis and physiological and biochemical characterization, strain KMM 9031Trepresents a novel species in a new genus, for which the namePacificibacter maritimusgen. nov., sp. nov. is proposed; the type strain is KMM 9031T( = NRIC 0785T = JCM 17096T).