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1.
  • 1.1. Histochemical, thin layer and gas-liquid chromatographic studies were done on neutral lipids, sterols and carotenes in the digestive gland-gonad (DGG) complex of Helisoma trivolvis infected with Echinostoma trivolvis vs uninfected DGG.
  • 2.2. Hitochemical Oil Red O staining showed the presence of neutral lipids in the redial body wall and in the digestive cells of the DGG.
  • 3.3. TLC showed that free sterols and triacylglycerols were major neutral lipid fractions along with lesser amounts of steryl esters and free fatty acids in the DGG of both populations. The percentage composition of all neutral lipid fractions was greater in infected than uninfected DGG.
  • 4.4. Infected DGG contained more carotenoid fractions than uninfected DGG, but only beta-carotene was identified from both.
  • 5.5. GLC studies showed that the major sterol present in snail DGG was cholesterol (about 70%) along with lesser amounts of stigmasterol, campesterol, beta-sitosterol and desmosterol. No clear cut distinction was seen in sterols from infected vs uninfected DGG.
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2.
  • 1.1. The lipid and fatty acid composition from the plasma and hemocytes in Octopus tehuelchus at different stages of sexual development, was determined.
  • 2.2. The highest content of lipids was found in females engaged in egg development, and the lowest in post-spawning and brooding females. Highest levels occurred during the autumn season in both sexes.
  • 3.3. Changes were mainly due to triacylglycerols and diacylglyceryl ethers.
  • 4.4. The plasma fatty acid composition did not demonstrate significant changes at different stages of maturation. The arachidonic acid (20:4 ω 6) was present at surprisingly high levels.
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3.
  • 1.1. The winter distribution of fatty acids in the fore and hind limb of the desert bighorn, Ovis canadensis cremnobates, increased in unsaturation distally over the length of the leg; the greatest change occurred at the level of the radius and tibia.
  • 2.2. Summer fatty acid marrow composition decreased significantly in unsaturation distally when compared to winter values. The greatest changes occurred at the metacarpus (metatarsus)-phalanges.
  • 3.3. The summer distribution of distally accumulated saturated fatty acids could be an adaptation to maintain the limbs as heat dissipators by insulating against conductive heat gain from a hot environment and protecting cell membranes of heterothermic tissues against thermal denaturation.
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4.
  • 1.1. Digestive gland and mantle fatty acids were studied in spring and summer in the bivalve Macoma balthica off the southern coast of Finland. The presence of lipids was also examined histochemically in various clam tissues.
  • 2.2. the neutral lipid content of the digestive gland increased ca 4.5-fold during the annual growth period.
  • 3.3. Neutral lipid fatty acids of the digestive gland, of which palmitoleic, eicosapentaenoic and palmitic acids were predominant, were clearly distinguished from phospho- and glycolipid fatty acids.
  • 4.4. The degree of unsaturation of phospholipid fatty acids was higher in the cold season both in the digestive gland and mantle, mainly due to the titer of eicosapentaenoic acid.
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5.
  • 1.1. Females, copepodid stages V and IV of Calanus finmarchicus were collected in Fram Strait area of the Arctic and in the northern North Sea to compare their lipid composition.
  • 2.2. For the comparison only copepods were considered which contained more than 8% of 18:4 fatty acid and high amounts of wax esters to exclude seasonal and spatial variabilities and different reproductive status of females.
  • 3.3. Animals are heavier in the Fram Strait area than in the North Sea with similar lipid proportion of dry weight and wax ester proportion of total lipid.
  • 4.4. Only some statistical significant differences exist between the fatty acid and alcohol compositions. The levels of 16:0 acid and alcohol and of 22:1 alcohol are higher and of 20:1 acid and alcohol are lower in the North Sea than in the Arctic.
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6.
  • 1.1. Three common species of North Atlantic krill, Meganyctiphanes norvegica (M. Sars), Thysanoessa inermis (Krøyer) and T. raschii (M. Sars), have been stored at 0°C post mortem, and the lipolytic activity followed by measuring changes in the lipid composition during storage.
  • 2.2. Both phosphoglycerides and triacylglycerols were subjected to extensive hydrolysis with the formation of free fatty acids in all krill species examined, whereas wax esters, constituting a considerable proportion of the lipids in the Thysanoessa species, were not hydrolysed at all.
  • 3.3. In M. norvegica the triacylglycerols and phosphoglycerides were hydrolysed at similar rates, whereas in T. inermis and T. raschii the phosphoglycerides were hydrolysed most rapidly.
  • 4.4. For all krill species examined, the rate of production of free fatty acids was nearly constant during the initial phase of storage, and subsequently declined on prolonged storage.
  • 5.5. At the end of the storage period of 16–24 days, the free fatty acids constituted about 35% of the total lipid in M. norvegica, and about 50% in the Thysanoessa species.
  • 6.6. The rate of production of free fatty acids was about the same in all the three species of krill and seemed to be independent of the total lipid content.
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7.
  • 1.1. The surface lipids of M. bivittatus, M. femurrubrum and M. dawsoni are similar to one another and similar to other Melanoplus previously studied.
  • 2.2. Secondary alcohol wax esters are among the major components of the cuticular lipids of these Melanoplus.
  • 3.3. Cast skins of M. bivittatus contain extractable triacylglycerols, free fatty acids, sterols, primary alcohols and secondary alcohols.
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8.
  • 1.1. Rhizostoma pulmo, Aurelia aurita and Actinia equina, the most widespread representatives of Coelenterata in Black Sea have been analysed and the occurrence of 20 sterols has been found.
  • 2.2. Dinosterol and demethyldinosterol as well as a number of short side chain sterols have been found in Scyphozoa for the first time.
  • 3.3. The occurrence of coprostanol in marine invertebrates has been shown for the first time.
  • 4.4. Five groups of sterol esters were found, containing fatty acids with different polarity.
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9.
  • 1.1. The quantitative and qualitative fatty acid composition of five Palythoa from the Senegalese coast and their associated organisms: Zooxanthellae symbiont or decapoda commensal have been determined by capillary G.C.
  • 2.2. The fatty acid compositiion of each associated organism, host and symbiont or commensal, presents enough characteristic differences to think that each of them synthesizes de novo its own fatty acids.
  • 3.3. These results suggest to us that the fatty acid composition of Palythoa and of Zooxanthellae might be a better and more useful tool for the taxonomic classification of these two families than sterol composition.
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10.
  • 1.1. Marabou feather lipids differ significantly from those of the uropygial gland secretion by the presence of sterols, sterol esters, di- and monoglycerides and free fatty acids.
  • 2.2. Triglycerides are converted into di- and monoglycerides in the plumage.
  • 3.3. The feather “bloom” during the nesting period consists of keratinous material, not lipid.
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11.
  • 1.1. The main purpose of the study was to describe and to compare the effect of different dietary fatty acids introduced at different levels into the diet on the positional distribution of fatty acids in rat body triacylglycerols. Only distribution between sn-2 (internal) and sn-1 + sn-3 (external) positions was considered in this study.
  • 2.2. The positional distribution of fatty acids was first determined for controls fed on a low fat diet (1% D.M.). The same study was then carried out with 11 different dietary treatments and results were systematically compared with controls. The effects of four main molecules were tested: linoleic acid, oleic acid, lauric acid and capric acid.
  • 3.3. Different alterations of the positional distribution of fatty acids in body triacylglycerols were obtained. They are graphically described and discussed.
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12.
  • 1.1. The ciliary membrane lipid composition and electrophysiology of the behavioral mutant of Paramecium tetraurelia, barium A (d4–592), were previously shown to differ from those of wild-type 51S when both strains were grown in low sterol medium.
  • 2.2. In this study, the phospholipid fatty acid composition of the two strains was shown to differ regardless of the level of sterol supplementation or culture age (growth phase).
  • 3.3. The ratio of linoleic to γ-linolenic acid, 18:2(9,12)/18:3(6,9,12), was consistently higher in baA compared to wild-type phospholipids, largely because of a dramatic shift in the ratio of these two fatty acids esterified at the 2 position of 1-alkyl-2-acyl-sn-glycero-3-phosphorylcholine (GPC).
  • 4.4. These data support the hypothesis that a specific Δ6 fatty-acyl desaturase, which directly desaturates phospholipid and shows a preference for GPC as its substrate, is impaired as a result of the barium A mutation.
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13.
  • 1.1. The fatty acid composition of the triglyceride fraction of mink milk sampled during mid-lactation (day 28 post partum) from two nursing mink was compared to that of plasma samples and to the fatty acid composition of the feed rations used.
  • 2.2. Chemical analysis of the triglyceride composition of mink milk demonstrated only minute concentrations of fatty acids with a chain length below C14.
  • 3.3. The saturated C16:0- and C18:0-unit fatty acids in mink milk made up for 24–40% of the total amount of fatty acids extracted, the remainder being represented by mono and polyunsaturated long-chain (C16-C24) fatty acids.
  • 4.4. Preliminary in vitro experiments proved the incorporation of14C-labelled glucose, acetate or palmitate into triacylglycerols in cultures of mink mammary tissue to be linear for at least 2 hr.
  • 5.5. The in vitro capacity for de novo fatty acid synthesis in mink mammary tissue using 14C-labelled glucose or acetate was low, i.e. ranging from 0.096–0.109 nmol/g (fresh tissue)/min, and amounted to only about 5% of that obtained in the case of [14C]palmitic acid incubation.
  • 6.6. Following 14C-labeIled acetic or palmitic acid incubation of mink mammary tissue neither desaturation nor chain elongation was observed.
  • 7.7. In response to long-term feeding on rations with two different sources of animal fat (F = fish oil or L = lard) the influence of compositional changes in dietary neutral lipids on the fatty acid composition of the lipids of mink milk is discussed.
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14.
  • 1.1. Influence of the biochemical composition of food (four species of micro-algae and one mixture) on the biochemical composition of gonads and larvae of O. edulis (total protein, lipid, carbohydrate, ash content, neutral and polar lipid class composition, amino acid composition and fatty acid composition of total, neutral and polar lipids) and the size of newly released larvae have been investigated.
  • 2.2. Precentage of total lipids and triacylglycerols in gonads depends on that in algae (r = 0.52 and 0.69 accordingly).
  • 3.3. Gonads rich in lipids had a higher level of triacylglycerols, phospholipids, polar lipids and a lower value of the ratio phosphatidylethanolamine/phosphatidylcholine (PE/PC) than gonads with a low lipid content.
  • 4.4. Amino acid composition of gonads depends on that of food, in this case, essential acids are preferentially accumulated (Asp acid, Ser, Ala, Cys, Tyr and Pro) and two non-essential (Thr and Lys).
  • 5.5. Fatty acid composition of total lipids of gonads was rather stable; except for the two essential acids 20:523 and 22:6w3, their percentage depends on that of food r = 0.65 and 0.65 accordingly). Fatty acid composition of neutral lipids was more diverse (in number and degree of variety) as compared to polar lipids.
  • 6.6. Larvae released from oysters with gonads rich in lipids had a higher percentage of lipids, triacylglycerols, size and a lower ash percentage and value of ratio PE/PC, as compared to larvae from gonads with low lipid content. Total lipid and triacylglycerol contents in gonads correlate rather well with those in larvae (r = 0.77 and 0.47 accordingly).
  • 7.7. Phospholipid class composition of larvae strongly depends on that of gonads. All the correlations are high and positive in character (except for phosphatidylinositol).
  • 8.8. Amino acid composition of larvae depends on that of gonads and, as in the case with gonads, the same essential acids are accumulated in the first place.
  • 9.9. Fatty acid composition of total lipids of newly released larvae was rather stable and independent on that of gonads except for total polyunsaturated acids (r = 0.70) and 20:5w3 (r = 0.65). Fatty acid composition of neutral lipids was lesser diverse (in number and degree of variation) as compared to polar lipids.
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15.
  • 1.1. The levels of non-esterified fatty acids (NEFA) in the plasma of a variety of animals have been estimated.
  • 2.2. Only one of seven elasmobranchs contained detectable levels of NEFA.
  • 3.3. The two crustaceans examined contained very low levels.
  • 4.4. All the other animals contained circulating levels of a variety of NEFA ranging from 14 to 24 carbon atoms.
  • 5.5. The elasmobranchs are unique in that they also do not possess proteins in the serum which bind fatty acids.
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16.
  • 1.1. Babesia hylomysci has an aminopeptidase and an acid endoprotease
  • 2.2. The amino-peptidase has properties very similar to the aminopeptidase in Plasmodium yoelii nigeriensis and P. chabaudi.
  • 3.3. The acid endoprotease is specific towards haemoglobin and practically has no action on bovine serum albumin.
  • 4.4. In mouse normal red blood cells we find an acid protease having physico-chemical properties similar to the enzyme present in B. hylomysci extracts.
  • 5.5. The similarity of electrophoretic velocity between acid protease in B. hylomysci and non-infected red blood cells leads us to think that the acid protease of parasitic extracts comes from the host-cell.
  • 6.6. The proteolytic system of Babesia and Plasmodium are similar.
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17.
  • 1.1. The wide-spread Black Sea mussels Mytilus galloprovincialis, Donax julianae, Cardium edule, Venus gallina, Mya arenaria and Tapes rugatus (Pelecypoda) as well as the snails Rapana thomasiana, Gibulla divaricata and Tritia reticulata (Gastropoda) were investigated for the presence of free sterols, sterol esters and epidioxisterols.
  • 2.2. The influence of some ecological factors upon the sterol composition, as well as some food-chains were studied.
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18.
  • 1.1. Cod, 2.6–3.4 kg. were fed a mixed diet of sprat, capelin oil and wheat flour.
  • 2.2. Lipids from the feed, stomach and four intestinal segments were separated into tri-, di- and monoglycerides and free fatty acids and analysed by GLC.
  • 3.3. All lipolytic products were concentrated in 14:0, 16:0 and 18:0, up to 60% and extremely low in the ω-3 fatty acids.
  • 4.4. Residual triglycerides contained 80% of saturated and monoenoic fatty acids.
  • 5.5. Linoleic acid increased from 2% in feed TG to 10% in TG of the rectum.
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19.
  • 1.1. Fatty acids were isolated from bacteria of the family Beggiatoaceae and closely related to the genus Thiothrix. These bacteria are symbionts that live in the gut of Echinocardium cordatum.
  • 2.2. Ten pronounced chromatographic peaks were observed that correspond to 14:0, 15:0, 15:0, 16:0, 16:1, 17:0, 18:0, 18:1, 18:3 and 19:0 fatty acids.
  • 3.3. The fatty acid 18:3 had a retention time and mass spectrum identical to those of linolenic acid.
  • 4.4. The presence of an essential fatty acid has never before been reported in a non-photosynthetic organism. This essential fatty acid in the symbiotic bacteria could be of nutritional importance for their echinoid host.
  • 5.5. The presence of this essential fatty acid supports a phylogenetic affinity between Beggiatoaceae and Cyanobacteria that are the only bacteria known to synthetize linolenic polyunsaturated fatty acid (PUFA).
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20.
  • 1.1. Four members of the genus Macoma: M. Balthica, M. irus, M.;incongrua; and M. contabulata from the Japan Sea were investigated for their sterol composition.
  • 2.2. Cholest-5-en-3β-ol was the most abundant sterol in all investigated animals; the other major sterols were common constituents of bivalves.
  • 3.3. The observed similarity in sterol composition of the studied clams seems to be an indication of greater influence of ecological than genetic factors on sterol composition.
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