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1.
Twelve marine algae of the Rhodophyta, 17 of the Phaeophyta and 5 of the Chlorophyta were analysed for their fatty acid content. It is possible that the fatty acid distribution may be useful for taxonomic purposes. It is found, that, as in higher plants, there are specific fatty acid distributions in the galactosyl diglycerides, e.g. the ω3 acids with the highest unsaturation are concentrated in the monogalactosyl diglycerides.  相似文献   

2.
ABSTRACT

Eight taxa of the Dipsacaceae family were examined for their fatty acid and sterol composition. Separation and identification of the lipid fraction was achieved by gas chromatography and gas chromatography-mass spectrometry. The phenotypic differences among taxa were established by cluster analysis. Correlation coefficients were obtained to investigate numerical relationships among constituents of the fatty acids. The results showed many significant correlations between different constituents, as well as four clusters of taxa using two linkage types of clustering.  相似文献   

3.
Abstract Fatty acids were identified in the submerged mycelium of Claviceps purpurea, Claviceps paspali, Claviceps fusiformis and Claviceps sp. SD-58 by gas chromatography-mass spectrometry (GC-MS) and used for a chemotaxonomical study. A close relatedness was found between Claviceps sp. SD-58 and C. fusiformis . The composition of fatty acids in high-production mutants differed substantially from that of the parent strains. Fatty acid analysis is thus probably only applicable in the taxonomy of non-mutated isolates of Claviceps cultured under standard conditions.  相似文献   

4.
Isoprenoid quinones and fatty acids ofZoogloea   总被引:1,自引:0,他引:1  
NineZoogloea strains including the type strain ofZ. ramigera (IAM 12136=ATCC 19544=N.C. Dondero 106) and newly isolated strains were investigated for isoprenoid quinone composition and whole-cell fatty acid profiles. Seven of the tested strains, having phenotypic properties typical ofZoogloea, were characterized by their production of both ubiquinone-8 and rhodoquinone-8 as major quinones, whereas the remaining two strains,Z. ramigera IAM 12669 (=K. Crabtree I-16-M) and IAM 12670 (=P.R. Dugan 115), formed ubiquinone-10 and ubiquinone-8, respectively, as the sole quinone. All rhodoquinone-producing strains contained palmitoleic acid and 3-hydroxy-decanoic acid as the major components of nonpolar and hydroxylated fatty acids, respectively. Marked differences were noted in the fatty acid composition between the strains with and without rhodoquinones. The chemotaxonomic data suggested that the rhodoquinonelacking strains should be excluded from the genusZoogloea. Since there have been no reliable taxonomic tools forZoogloea, rhodoquinone analysis may provide a new criterion of great promise for identifyingZoogloea strains.  相似文献   

5.
Four species of Nyssa, eleven species of Cornus, and one species each of Davidia, Camptotheca, Aucuba, and Mastixia were analyzed for seed oil fatty acids. Canonical variates calculated from percentage palmitic stearic, oleic, linoleic and linolenic acids show that Nyssa biflora lies intermediate to N. sylvatica and N. aquatica in composition. Davidia involucrata should remain allied with the Nyssaceae. Many of the Cornus species from several subgenera comprise a single cluster that represents a fatty acid composition at or near the primitive condition.  相似文献   

6.
Marine organisms, in particular invertebrates, have proved to be a major source of unique fatty acid (FA) structures originating from unusual biosynthetic pathways. Among them, non-methylene-interrupted (NMI) FA occur in various molluscs in the wide ranges of concentrations (up to 20%), such as the most often encountered 20:2 Δ5,11, 20:2 Δ5,13, 22:2 Δ7,13 or 22:2 Δ7,15. Such NMI FA have also been reported from algae, echinoderms, sponges, tropical rays, and many other invertebrates. The most intriguing marine invertebrates seem to be sponges that commonly contain very long-chain Δ5,9 FA. A third double bond can occur in the NMI FA as reported in some marine organisms, such as 20:3 Δ7,13,16 or 30:3 Δ5,9,23. Lipids of invertebrates from deep-sea hydrothermal and cold-seep vents gave rise to an intense research activity including reports on unprecedented NMI polyunsaturated FA. The bivalve molluscs are able to synthesize de novo the NMI FA but their precise biological interest is presently not well-known, although structural and functional roles in biological membranes have been suggested, in particular a higher resistance to oxidative processes and microbial lipases. Biosynthetic pathways of Δ5,9 FA in sponges were demonstrated up to C26 FA structures and include particular elongation and desaturation steps. Recently, intense research effort has been conducted to investigate the biomedical potential of these unusual FA. Thus, Δ5,9 FA displayed interesting antiplasmodial activity. The most promising FA topoisomerase I inhibitors to date seem to be the long-chain Δ5,9 FA. This inhibitory activity is probably partially responsible for the toxicity displayed by some of the Δ5,9 FA towards cancer cell lines.  相似文献   

7.
The fatty acid, sterol and chlorophyll pigment compositions of the marine dinoflagellates Gymnodinium wilczeki and Prorocentrum cordatum are reported. The fatty acids of both algae show a typical dinoflagellate distribution pattern with a predominance of C18, C20 and C22 unsaturated components. The acid 18:5ω3 is present at high concentration in these two dinoflagellates. G. wilczeki contains a high proportion (93.4%) of 4-methyl-5α-stanols including 4,23,24-trimethyl-5α-cholest-22E-en-3β-ol (dinosterol), dinostanol and 4,23,24-trimethyl-5α-cholest-7-en-3β-ol reported for the first time in dinoflagellates. The role of this sterol in the biosynthesis of 5α-stanols in dinoflagellates is discussed. P. cordatum contains high concentrations of a number of δ 24(28)-sterols with dinosterol, 24-methylcholesta-5,24(28)-dien-3β-ol, 23,24-dimethylcholesta-5,22E-dien-3β-ol, 4,24-dimethyl-5α-cholest-24(28)-en-3β-ol and a sterol identified as either 4,23,24-trimethyl- or 4-methyl-24-ethyl-5α-cholest-24(28)-en-3β-ol present as the five major components. The role of marine dinoflagellates in the input of both 4-methyl- and 4-desmethyl-5α-stanols to marine sediments is discussed.  相似文献   

8.
Nine sterols, most showing Δ5- or Δ5,22-unsaturation, were identified in the marine diatom Biddulphia sinensis. One sterol, cholesta-5,22E-dien-3β-ol, comprised 70–80% of the total sterols which is the first such predominance noted in a diatom. The only Δ7-sterol detected was cholest-7-en-3β-ol and this was a very minor component. A sterol showing unusual side-chain alkylation,23,24-dimethylcholesta-5,22E-dien-3β-ol, was identified for the first time in a diatom. Total fatty acids exhibited a predominance of Δ9- 16:1, 14:0, 20:5 and 16:0, typical of diatoms, although the proportions of these acids were found to vary with culture maturity. n-Heneicosahexaene was the major hydrocarbon together with a small amount of squalene.  相似文献   

9.
The intra-and interspecific variability of fatty acid (FA) composition of soft corals was examined in the tropical alcyonarian Sarcophyton sp., tropical gorgonian Euplexaura erecta, and boreal alcyonarian Gersemia rubiformis. Characteristic significant differences in the FA composition were found between these species belonging to different taxonomic groups and habitats. We assume that the FA groups 14: 0 + 16: 0 + 18: 3n-6, 16: 2 + 20: 4n-6 + 24: 5n-6, and 18: 1n-7 + 20: 1n-7 + 20: 5n-3 + 24: 6n-3 are characteristic of Sarcophyton sp., E. erecta, and G. rubiformis respectively. There were no significant differences (p > 0.05) between the three soft coral species in the content of oleic, linoleic, and docosahexaenoic acids. The relative content of more than 45% of individual FA did not significantly differ (p > 0.05) between the pairs of species, i.e., intraspecific variations exceeded interspecific ones. The reasons for intraspecific variability of soft coral FA composition are discussed. Control of this variability is needed when using individual FA as chemotaxonomic and food markers.  相似文献   

10.
马蹄参属种子油脂肪酸的特征及其分类学意义   总被引:3,自引:0,他引:3  
用气相色谱质谱方法分析了马蹄参(DiplopanaxstachyanthusHand.Mazz.)和近缘属植物挤果树参(DendropanaxconfertusLi)、桃叶珊瑚(AucubajaponicaThunb.)、毛(CornuswalteriWanger.)、八角金盘〔Fatsiajaponica(Thunb.)Dence.etPlanch.〕的种子油脂肪酸成分。结果表明在所测定的马蹄参种子油样本中含量最高的成分是亚油酸C18∶2(9C,12C),同时含有岩芹酸C18∶1(6C)这一异常脂肪酸。种子油脂肪酸分布特征支持将马蹄参属移出五加科,改隶于广义的山茱萸科。  相似文献   

11.
Twenty-eight axenio planktonic cyanobacterial strains (10 Microcystis, three Oscillatoria, one Spirulina, one Aphanizomenon, 13 Anabaena) were investigated for their fatty acid composition by measurement of non-polar and hydroxy fatty acids. No 2-hydroxy fatty acids were detected in any strain, but 3-hydroxy fatty acids were detected in minor quantities in 24 strains. The highest portion of total fatty acids were non-polar fatty acids. Qualitative and quantitative analyses of 3-hydroxy fatty acids showed no taxonomic value in these strains, while the type of non-polar fatty acid composition was shown to be consistent within Microcystis and Anabaena strains, distinguishing them as type 4, characterized by the presence of 18:4, and type 2, characterized by 18:3 (α) of the Kenyon-Murata system. Two Oscillatoria agardhii Gomont strains were also included in the type 2 group due to the presence of 18: 3 (α), but the difference in characteristics of 16:2 and 16:3 between O. agardhii and Anabaena further divided type 2 into two subgroups: type 2A for Anabaena and type 2B for O. agardhii. A simplified unweighted pair group method with arithmetic averages (UPGMA) dendrogram demonstrated that the classification of 28 strains (Microcystis spp., Anabaena spp., Aphanizomenon flos-aquae (Lemmermann) Ralfs f. gracile (Lemmermann) Elenkin, O. agardhii and Spirullnasubsalsa Oersted ex Gomont based on numerical analysis of non-polar fatty acids corresponded to morphological species criteria, suggesting that non-polar fatty acid composition is a valuable chemical marker in the taxonomy of planktonic cyanobacteria. However, the fatty acid composition in Oscillatoria raciborskii is similar to that of Microcystis and very different from that of O. agardhii, suggesting its special position in Oscillatoria and the chemical diversity in the genus Oscillatoria.  相似文献   

12.
13.
Abstract The polar lipids of 5 species of Thiobacillus were extracted and purified. An analysis of the fatty acid composition of the polar lipids documented the presence of methoxy, cyclopropyl, monounsaturated and hydroxycyclopropyl fatty acids of sufficiently unusual structure to serve as 'signatures' for the presence of these organisms in environmental samples. The structures of the unusual fatty acids of the polar lipids were confirmed by mass spectrometry (MS) after isolation by capillary gas chromatography (GC).  相似文献   

14.
Fatty acid compositions of the lipids isolated from the pinnae of four fern species show that they differ from those of the lipids in leaves of higher plants in having C-20 polyunsaturated acids, mainly arachidonic acid. As in higher plants, the ω-3 polyunsaturated acids are concentrated in the monogalactosyl diglycerides. Variations are found both in the fatty acid compositions and in the monogalactosyl/digalactosyl diglyceride ratio during the growing season.  相似文献   

15.
Summary Radioiodinated free fatty acids have been developed to study myocardial metabolism non-invasively in man. In the present study the distribution of radiolabeled lipids in the myocardium and in arterial and coronary sinus blood was evaluated following injection of three commonly used iodinated fatty acids in fasted (n = 5) and lactate loaded (n = 3) dogs. Five minutes after simultaneous i.v. injection of radioiodinated 17-I-heptadecanoic acid (IHDA),15-(p-I-phenyl) pentadecanoic acid (IPPA) and 15-(p-I-phenyl)-3,3-dimethylpentadecanoic acid (DMIPPA) a biopsy specimen and samples of arterial and coronary sinus blood were taken. After extraction and TLC the relative distribution of radioactivity in the aqueous phase (containing the oxidation products), pellet and organic phase was calculated. The organic phase was further divided into phospholipids, diglycerides, free fatty acids, triglycerides and cholesterolesters. Seventy two percent of IHDA was oxidized, 36% of IPPA and 7% of DMIPPA. The organic phase consisted primarily of triglycerides and phospholipids. The ratios of triglycerides to phospholipids were about the same for IHDA, IPPA and DMIPPA (0.58, 0.65 and 0.50, respectively). Free IHDA in tissue samples was low (4%) and elevated for IPPA and DMIPPA, (17% and 37%). During lactate loading triglycerides were higher for all three fatty acids. For IHDA and IPPA this increase was paralleled by a decrease in the aqueous phase, in case of DMIPPA the aqueous phase remained the same. Five minutes after injection most of the organic phase of both arterial and coronary sinus blood consisted of the injected fatty acids, the aqueous phase contained oxidation products. There were only minor differences during lactate loading. During the evaluation of scintigraphic patterns of the radioiodinated fatty acids under normal conditions (eg at rest) and during elevated lactate levels (eg during exercise) the differences in distribution must therefore be considered.  相似文献   

16.
The sterol and fatty acid compositions of fresh leaves of the seagrasses Cymodocea serrulata, Enhalus acoroides, Halodule uninervis, Halophila ovalis, H. ovata, H. spinulosa and Thalassia hemprichii are reported. The major fatty acids were palmitic acid, linoleic acid and linolenic acid as expected. H. ovalis and H. ovata were characterized by the relatively high abundance (ca 5%) of the acid hexadeca-7,10,13-trienoic acid (16:3<7 > ). The sterol compositions were typical of higher plants, with sitosterol and stigmasterol accounting for 60–90% of the observed sterols. 28-Isofucosterol was a major sterol (20–30%) only in the Halophila spp. Cluster analysis of the sterol composition data clearly separated the Halophila spp. from the other seagrasses and enabled the distinction of Enhalus sp. from Cymodocea, Halodule and Thalassia spp. The seagrass species were clearly separated into five chemical groups using the combined fatty acid and sterol composition data and the need for a reappraisal of the taxonomic position of Halophila was indicated.  相似文献   

17.
The experimental criteria, principally GLC behaviour and spectroscopic data, by which ω-cycloalkyl fatty acids (cyclobutyl to cycloheptyl, C14 to C21) can be identified, are described.  相似文献   

18.
The fatty acid composition of the biotrophic white rust species A. amaranthi, A. candida and A. tragopogonis was identified by means of GC and GC/MS analysis. Besides the common saturated fatty acids of C14 to C22 chain length, several unusual monounsaturated and polyunsaturated fatty acids were present in significant amounts in the lipid profiles of the three species. Each taxon revealed its own characteristic pattern which was uniform among populations of different geographic origin and independent from the host species. Fatty acids were obtained from minute amounts of sporangia collected from the surface of desiccated host plants. Comparison of herbarium specimens revealed a decrease of polyunsaturated compounds after storage for 30 months at room temperature, but still allowed unquestionable species differentiation.  相似文献   

19.
Fatty acid composition of the total lipids isolated from the fresh-water green alga Ulothrix aequalis shows that they resemble marine green algal lipids in having a high proportion of 16:4 ω-3 but differ in having only trace amounts of 18:4 ω-3. The distribution of ω-3 acids in the MGDG and DGDG fractions resembles that in green seaweeds and higher plants with the 16:4 ω-3 distribution in the Ulothrix fractions resemblmg that of 18:4 ω-3 in the corresponding fractions of the seaweeds.  相似文献   

20.
Oxygen free radicals damage cells through peroxidation of membrane lipids. Gastrointestinal mucosal membranes were found to be resistant to in vitro lipid peroxidation as judged by malonaldehyde and conjugated diene production and arachidonic acid depletion. The factor responsible for this in this membrane was isolated and chemically characterised as the nonesterified fatty acids (NEFA), specifically monounsaturated fatty acid, oleic acid. Authentic fatty acids when tested in vitro using liver microsomes showed similar inhibition. The possible mechanism by which NEFA inhibit peroxidation is through iron chelation and iron-fatty acid complex is incapable of inducing peroxidation. Free radicals generated independent of iron was found to induce peroxidaton of mucosal membranes. Gastrointestinal mucosal membranes were found to contain unusually large amount of NEFA. Circulating albumin is known to contain NEFA which was found to inhibit iron induced peroxidation whereas fatty acid free albumin did not have any effect. Addition of individual fatty acids to this albumin restored its inhibitory capacity among which monounsaturated fatty acids were more effective. These studies have shown that iron induced lipid peroxidation damage is prevented by the presence of nonesterified fatty acids.  相似文献   

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