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1.
The fatty acid (FA) composition of vacuolar membrane lipids from the storage tissues of parsnip (Pastinaca sativa L.), parsley (Petroselinum crispum L.), and carrot (Daucus carota L.) was studied by gasliquid chromatography, and possible pathways of the biosynthesis of these acids are considered. A high level of unsaturated FAs (up to 78% of the total FA amount) was characteristic of these membrane lipids with the predominance of linoleic acid, which content in vacuolar lipids of parsnip, parsley, and carrot was 53.5, 55.1, and 54.4%, respectively. A high content of hexadienoic acid (C16:2ω6) was characteristic of the vacuolar lipids of parsnip and parsley (8.0 and 4.6%. respectively); the content of α-linolenic acid in the vacuolar lipids of these plants was 4.4–7.3%. Palmitic acid predominated among the saturated FAs (18.0–20.4%).  相似文献   

2.
Fatty acid composition and structure in total lipids from the green above-ground parts of four alpine plants, Oxygraphis glacialis, Primula macrophylla, Rhodiola pamiroalaica, and Swertia marginata, were established by GC and GC-MS. A total of 55 fatty acids was detected, and 48 of them were identified. Ubiquitous palmitate, linoleate, and linolenate predominated in the lipids accounting for about 72-90% of the total fatty acids. At the same time, the latter contained numerous species, which were unusual for higher plants and included saturated odd-numbered n-acids (six C15-C25 species, 0.26-1.40%), saturated even-numbered very-long-chain n-acids (six C20-C30 species, 1.00-2.49%), iso-acids (nine C15-C26 species, 0.64-1.53%), anteiso-acids (four C15-C20 species, 0.08-1.57%), certain uncommon mono- and dienoic acids, as well as 16:3omega3, 18:3omega6, and 18:4omega3 acids that are absent from the most higher plants. Nine fatty acids were found here for the first time in higher plants and two may be new to science. The evidence on the unusual fatty acids is discussed with respect to their distribution in living organisms, pathways of biosynthesis, and chemotaxonomic role.  相似文献   

3.
Diet and postnatal age effect the fatty acid composition of plasma and tissue lipids. This work was designed as a transversal study to evaluate the changes in the fatty acid composition of plasma phospholipids, cholesteryl esters, triglycerides and free fatty acids in preterm infants (28-35 weeks gestational age), fed human milk (HM) and milk formula (MF) from birth to 1 month of life. Sixteen blood samples were obtained from cord, and 19 at 6-8 h after birth, 14 at 1 week and 9 at 4 weeks from HM-fed infants and 18 at 1 week and 14 at 4 weeks from MF-fed ones. Groups had similar mean birth weight, gestational age and sex ratio. The MF provided 69 kcal/dl and contained 16% of linoleic acid and 1.3% of alpha-linolenic acid on the total fat. Plasma lipid fractions were extracted and separated by thin-layer chromatography and fatty acid methyl esters were quantitated by gas liquid chromatography. In plasma phospholipids, linoleic acid (18:2 omega 6) continuously increased from birth to 1 month of age, but no changes were seen as related to type of diet; polyunsaturated fatty acids greater than 18 carbon atoms of both the omega 6 and omega 3 series (PUFA omega 6 greater than 18 C and omega 3 greater than 18 C) dropped from birth to 1 week and continued to decrease in MF-fed infants until 1 month; eicosatrienoic (20:3 omega 6), arachidonic (20:4 omega 6) and docosahexaenoic (22:6 omega 3) were the fatty acids implicated. In cholesteryl esters palmitoleic (16:1 omega 7) and oleic (18:1 omega 9) acids decreased from birth to 1 month and linoleic acid increased and arachidonic acid dropped, especially in MF fed infants. In triglycerides, palmitic, palmitoleic and stearic acid (18:0) decreased during the first month of life; oleic acid remained constant and linoleic acid increased in all infants, but arachidonic acid decreased only in those fed formula. Free fatty acids showed a similar behavior in fatty acids and in plasma triglycerides. Preterm neonates seem to have special requirements of long-chain PUFA and adapted MF should contain these fatty acids in similar amounts to those of HM to allow the maintenance of an adequate tissue structure and physiology.  相似文献   

4.
We have hypothesized that among algae of alpine environment there could be strains particularly rich in long chain polyunsaturated fatty acids (LC-PUFA). Indeed, the chlorophyte (Trebuxiophyceae) Parietochloris incisa isolated from Mt. Tateyama, Japan, was found to be the richest plant source of the pharmaceutically valuable LC-PUFA, arachidonic acid (AA, 20:4omega6). The alga is also extremely rich in triacylglycerols (TAG), which reaches 43% (of total fatty acids) in the logarithmic phase and up to 77% in the stationary phase. In contrast to most algae whose TAG are made of mainly saturated and monounsaturated fatty acids, TAG of P. incisa are the major lipid class where AA is deposited, reaching up to 47% in the stationary phase. Except for the presence of AA, the PUFA composition of the chloroplastic lipids resembled that of green algae, consisting predominantly of C(16) and C(18) PUFAs. The composition of the extrachloroplastic lipids is rare, including phosphatidylcholine (PC), phosphatidylethanolamine (PE) as well as diacylglyceryltrimethylhomoserine (DGTS). PC and PE are particularly rich in AA and are also the major depots of the presumed precursors of AA, l8:3omega6 and 20:3omega6, respectively.  相似文献   

5.
The changes of children myocardium lipid composition were studied for the first time during surgical intervention under cold crystalloid cardioplegia. The surgical intervention was performed as a result of congenital heart disease--atrial septal defect. It was shown that the quantity of short chain fatty acids decreased and the amount of long chain fatty acids increased in the content of phospholipid fraction. Simultaneously the amount of linoleic (C18:2 omega 6), of docosahexaenoic (C22:6 omega 3) and of some other fatty acids decreased in the content of cholesterol esthers. The accumulation of free linoleic (C18:2 omega:6), (C18:2 omega:4) and linolenic (C18:3 omega:6) acids was found. Reperfusion caused the additional changes of myocardium lipid composition. The amount of palmitic (C16:0) acid decreased by 30%. The quantity of some other saturated free fatty acids also diminished. Simultaneously the content of free oleic (C18:1 omega 9) also decreased as a consequence of lipid peroxidative processes activation. The ratio of omega 6/omega 3 increased during the few first minutes of reperfusion in the fraction of free fatty acids and cholesterol esthers.  相似文献   

6.
The vitamin composition of representatives of green (Chlorella vulgaris, Platimonas viridis), blue-green (Synechococcus elongatus, Coccopedia, Spirulina platensis, Cyanidium caldarium), red (Porphyridium cruentum) unicellular algae and higher plants (wheat, chufa, beet, carrot, turnip, radish, cucumber, dill, Welsh onion, potato) grown under artificial conditions was examined. The content of B complex vitamins (thiamine, riboflavine, nicotinic and folic acids), ascorbic acid and carotene was measured. Among the algae studied Chlorella vulgaris and Spirulina platensis showed the highest vitamin activity. The red alga Porphyridium cruentum contained the lowest quantity of thiamine, riboflavine and carotene and larger amounts of nicotinic acid. Comparison of the content of vitamins C, B1, B2, PP, folic acid and carotene in unicellular algae and higher plants, that are natural and traditional sources of the vitamins, demonstrated that the above green and blue-green algae contain greater than higher plants amounts of thiamine, riboflavine, folic acid and carotene, when calculated per g dry matter. All algae, except for Platimonas viridis and Cyanidium caldarium, are superior to beet and carrot in their content of ascorbic acid and inferior to green vegetables (radish, cabbage, dill and Welsh onion) in that parameter.  相似文献   

7.
The polyunsaturated fatty acid composition of Brugia malayi microfilariae was analyzed by gas chromatography and compared to that of sera from B. malayi-infected jirds. The essential fatty acid, linoleic acid (18:2 omega 6), was the most abundant fatty acid present in both microfilarial total lipids and phospholipids as well as in jird sera. In contrast, arachidonic acid (20:4 omega 6), as well as the 18:3 omega 6, 20:2 omega 6, and 20:3 omega 6 intermediates that are formed in the enzymatic conversion of linoleic acid to arachidonic acid, were proportionally more abundant in microfilariae than in jird sera. To assess the capacity of microfilariae to transform linoleic acid into arachidonic acid, B. malayi microfilariae were incubated with [14C]linoleic acid. Microfilarial lipids were extracted and resolved by high-pressure liquid chromatography and thin-layer chromatography. A portion of [14C]linoleic acid incorporated by microfilariae was converted to [14C]arachidonic acid. Thus, microfilariae can not only incorporate exogenous arachidonic acid, as previously demonstrated, but can also synthesize arachidonic acid from exogenous linoleic acid. The capacity of microfilariae to utilize specific host polyunsaturated fatty acids raises the possibility that intravascular filarial parasites may synthesize eicosanoid metabolites of arachidonic acid that could mediate filarial-host cell interactions.  相似文献   

8.
Studies were conducted to characterize the metabolism of the unusual fatty acid petroselinic acid (18:1cis[delta]6) in developing endosperm of the Umbelliferae species coriander (Coriandrum sativum L.) and carrot (Daucus carota L.). Analyses of fatty acid compositions of glycerolipids of these tissues revealed a dissimilar distribution of petroselinic acid in triacylglycerols (TAG) and the major polar lipids phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Petroselinic acid comprised 70 to 75 mol% of the fatty acids of TAG but only 9 to 20 mol% of the fatty acids of PC and PE. Although such data appeared to suggest that petroselinic acid is at least partially excluded from polar lipids, results of [1-14C]acetate radiolabeling experiments gave a much different picture of the metabolism of this fatty acid. In time-course labeling of carrot endosperm, [1-14C]acetate was rapidly incorporated into PC in high levels. Through 30 min, radiolabel was most concentrated in PC, and of this, 80 to 85% was in the form of petroselinic acid. One explanation for the large disparity in amounts of petroselinic acid in PC as determined by fatty acid mass analyses and 14C radiolabeling is that turnover of these lipids or the fatty acids of these lipids results in relatively low accumulation of petroselinic acid mass. Consistent with this, the kinetics of [1-14C]acetate time-course labeling of carrot endosperm and "pulse-chase" labeling of coriander endosperm suggested a possible flux of fatty acids from PC into TAG. In time-course experiments, radiolabel initially entered PC at the highest rates but accumulated in TAG at later time points. Similarly, in pulse-chase studies, losses in absolute amounts of radioactivity from PC were accompanied by significant increases of radiolabel in TAG. In addition, stereospecific analyses of unlabeled and [1-14C]acetate-labeled PC of coriander endosperm indicated that petroselinic acid can be readily incorporated into both the sn-1 and sn-2 positions of this lipid. Because petroselinic acid is neither synthesized nor further modified on polar lipids, the apparent metabolism of this fatty acid through PC (and possibly through other polar lipids) may define a function of PC in TAG assembly apart from its involvement in fatty acid modification reactions.  相似文献   

9.
Lipid content and fatty acid composition were determined in three species of edible fish caught in Senegalese waters during the upwelling season (January, 1993). Sardinella maderensis and Sardinella aurita are fat fish containing more than 5% (fresh wt.) of lipids, whereas Cephalopholis taeniops is a lean fish with approximately 1% of lipids. Skin, liver and muscle were studied for each fish species. About 40 fatty acids were identified by GC and GC/MS as methyl esters and N-acyl pyrrolidides. Palmitic acid was the main acid in the muscle and skin of all samples studied (20-33% of total fatty acids). Oleic acid was the main fatty acid in the liver of S. maderensis (27.2%+/-0.1) and S. aurita (44.7%+/-0.1). Arachidonic acid was a minor component in all samples. The flesh (muscle) of the three fish species contained high concentrations of omega3 polyunsaturated fatty acids (PUFA), ranging from 16.0 to 29.1% and including 20:5 omega3 (eicosapentaenoic acid, EPA) and 22:6 omega3 (docosahexaenoic acid, DHA) acids as major components. These two acids together accounted for 24.7%+/-0.1 and 12.9%+/-0.1 of total acids in the skin of S. maderensis and S. aurita, respectively. The percentages of PUFA found in the fish studied were very similar to those in fish used commercially as sources of PUFA. Muscle sterols, which accounted for 9-11% of total lipids, consisted mainly of cholesterol (up to 97% of total sterols).  相似文献   

10.
1. [1-14C]linolenic acid was injected into the rainbow trout, Salmo gairdnerii, ayu, Plecoglossus altivelis, eel, Anguilla japonica, red sea bream, Chrysophrys major, rockfish, Sebastiscus marmoratus, globefish, Fugu rubripes rubripes and prawn, Penaeus japonicus (molting stage D"1-D2), and the bioconversion of linolenic acid (18:3 omega 3) to highly unsaturated fatty acids such as eicosapentaenoic (20:5 omega 3) and docosahexaenoic (22:6 omega 3) acids was investigated. 2. Linolenic acid was converted to 20:5 omega 3 and 22:6 omega 3 intensively in the rainbow trout, moderately in the ayu, eel and prawn, but slightly in the red sea bream, rockfish and globefish. 3. These results were discussed in relation to the essential fatty acid requirements of the aquatic animals.  相似文献   

11.
The fatty acid composition of lipids was studied in Penicillium fungi growing in different habitats. Saturated fatty acids were represented by lauric, margaric, stearic and palmitic acids (the latter prevailed-- 18%-26%). Unsaturated monoene fatty acids were represented by acids from C16:1 to C18:1, diene and triene fatty acids by linoleic and linolenic acids. The predominance of linoleic acid was not found in all cultures of the genus. Changes in the fatty acid composition of lipids may be attributed to different ecological habitats of the Penicillium genus species.  相似文献   

12.
The freshwater green microalga Parietochloris incisa is the richest known plant source of the polyunsaturated fatty acid (PUFA), arachidonic acid (20:4omega6, AA). While many microalgae accumulate triacylglycerols (TAG) in the stationary phase or under certain stress conditions, these TAG are generally made of saturated and monounsaturated fatty acids. In contrast, most cellular AA of P. incisa resides in TAG. Using various inhibitors, we have attempted to find out if the induction of the biosynthesis of AA and the accumulation of TAG are codependent. Salicylhydroxamic acid (SHAM) affected a growth reduction that was accompanied with an increase in the content of TAG from 3.0 to 6.2% of dry weight. The proportion of 18:1 increased sharply in all lipids while that of 18:2 and its down stream products, 18:3omega6, 20:3omega6 and AA, decreased, indicating an inhibition of the Delta12 desaturation of 18:1. Treatment with the herbicide SAN 9785 significantly reduced the proportion of TAG. However, the proportion of AA in TAG, as well as in the polar lipids, increased. These findings indicate that while there is a preference for AA as a building block of TAG, the latter can be produced using other fatty acids, when the production of AA is inhibited. On the other hand, inhibiting TAG construction did not affect the production of AA. In order to elucidate the possible role of AA in TAG we have labeled exponential cultures of P. incisa kept at 25 degrees C with [1-14C]arachidonic acid and cultivated the cultures for another 12 h at 25, 12 or 4 degrees C. At the lower temperatures, labeled AA was transferred from TAG to polar lipids, indicating that TAG of P. incisa may have a role as a depot of AA that can be incorporated into the membranes, enabling the organism to quickly respond to low temperature-induced stress.  相似文献   

13.
Fatty acid (FA) composition of vacuolar membrane lipids from storage tissues of umbelliferous plants, viz., parsnip (Pastinaca sativa L.), parsley (Petroselinium crispum L.), and carrot (Daucus carota L.) is studied by gas-liquid chromatography and the FA biosynthetic pathways are considered. Vacuolar membrane lipids are characterized by high (78% of the total FA pool) content of unsaturated FA among which linoleic acid is predominant. Its content in vacuolar lipids of parsnip, parsley and carrot is 53.5, 55.1, and 54.9%, respectively. Parsnip and parsley vacuolar lipids contain large amounts of hexadecadienoic C16:2ω6 acid (8.0 and 4.6%, respectively). The content of α-linolenic acid in vacuolar lipids of tested plants varies from 4.8 to 7.3%. Palmitic acid (18.0–20.7%) predominates among saturated FA. High content of linoleic and hexadecadienoic acid in parsnip and parsley vacuolar lipids is suggestive of a crucial role of the microsomal ω6 fatty-acid desaturase fad2 gene in resistance and acclimation of plants to low temperatures.  相似文献   

14.
Incorporation of [1-14C]palmitic (16:0) and [1-14C]linoleic (18:2 omega 6) acids into microsomal membranes of proximal (jejunum) and distal (ileum) regions of rat small intestine was investigated, and the lipid composition, including fatty acid profiles of membrane phospholipids, was determined. Jejunal microsomes contained significantly higher amounts of total phospholipids, phosphatidylcholine, and phosphatidylinositol, and lower amounts of cholesterol and sphingomyelin when compared with ileal microsomes. Jejunal microsomal phospholipids contained higher levels of stearic (18:0), 18:2 omega 6, and eicosapentaenoic (20:5 omega 3) acids followed by reduced levels of oleic (18:1 omega 9), arachidonic (20:4 omega 6), and docosahexaenoic (22:6 omega 3) acids when compared with those from the ileum, except for phosphatidylinositol where no significant difference between 20:4 omega 6 content of each site was observed. In both jejunal and ileal microsomes, incorporation of [1-14C]18:2 omega 6 was significantly higher than that of [1-14C]16:0. Incorporation of both [1-14C]16:0 and [1-14C]18:2 omega 6 was significantly higher in jejunal microsomal lipid fractions (phospholipids, diacylglycerols, triacylglycerols) when compared with the ileal microsomal fraction. These data suggest that (1) jejunal and ileal microsomal membranes differ from each other in terms of lipid composition and lipid synthesis, (2) site variations in the specificity of acyltransferases for different fatty acids exist, and (3) higher delta 9-, delta 6-, delta 5-, and delta 4-desaturase activities exist in ileal compared with jejunal enterocytes.  相似文献   

15.
Fatty acid composition of lipids which copurify with band 3   总被引:1,自引:0,他引:1  
In a previous study (L. R. Maneri and P. S. Low (1988) J. Biol. Chem. 263, 16170-16178) we determined that the anion transport protein, band 3, was significantly stabilized by lipids containing saturated and/or long chain fatty acids. To determine whether this thermodynamic preference is reflected in the composition of lipids tightly associating with the anion transporter in vivo, we have analyzed the fatty acid content of phospholipids co-isolating with the purified integral domain of band 3. Our data demonstrate that although stearic acid comprises only 14% of the bulk lipid fatty acids of the red cell membrane, it constitutes -68% of the fatty acids of lipids co-isolating with band 3. Certain other long chain fatty acids were also enriched in the adherent lipids. These results suggest that the fatty acids which most effectively stabilize band 3 also have the highest affinity for the transport protein.  相似文献   

16.
Rats depleted in long-chain polyunsaturated omega3 fatty acids (omega3-depleted rats) display several features of the metabolic syndrome including hypertension and cardiac hypertrophy. This coincides with alteration of the cardiac muscle phospholipid and triacylglycerol fatty acid content and/or pattern. In the present study, the latter variables were measured in the cardiac endothelium of normal and omega3-depleted rats. Samples derived from four rats each were obtained from 16 female normal fed rats and three groups of 36-40 female fed omega3-depleted rats each aged 8-9, 15-16 and 22-23 weeks. At comparable mean age, the ratio between the square root of the total fatty acid content of phospholipids and cubic root of the total fatty acid content of triacylglycerols was lower in omega3-depleted rats than in control animals. The total fatty acid content of triacylglycerols was inversely related to their relative content in C20:4omega6. Other differences between omega3-depleted rats and control animals consisted in a lower content of long-chain polyunsaturated omega3 fatty acids in both phospholipids and triacylglycerols, higher content of long-chain polyunsaturated omega6 fatty acids in phospholipids, higher activity of delta9-desaturase (C16:0/C16:1omega7 and C18:0/C18:1omega9 ratios) and elongase [(C16:0 + C16:1omega7)/(C18:0 + C18:1omega9) and C20:4omega6/C22:4omega6 ratios], but impaired generation of C22:6omega3 from C22:5omega3 in the former rats. These findings support the view that cardiovascular perturbations previously documented in the omega3-depleted rats may involve impaired heart endothelial function.  相似文献   

17.
TLC, GLC and GC-MS methods were applied for studying the fatty acid composition of rat cerebellum phospholipids. 75 male Wistar rats had a diet without fat for 6 weeks and then a diet with linseed oil, fish oil in combination with lard and mixture of sunflower oil with lard (control group) for 3 months; PUFA omega 6/omega 3 rations were 0.27; 0.5 and 45.0. PUFA omega 3 in all fractions were represented mainly by 22:6 omega 3 (0.2-12.0%) acid and its share depends on the total PUFA omega 3 amount in the diet. The absence of 18:3, 20:5 and 22:5 omega 3 in cerebellum lipids, fed in great amount with test diets, suggested that these acids are rapidly desaturated and elongated to 22:6 omega 3 at the blood-brain barrier. Established competitive inhibition of desaturases responsible for the synthesis of tissues PUFA omega 6 and omega 3 proves the expressed regulatory effect of alimentary factor on brain lipids.  相似文献   

18.
Algae have been explored for renewable energy, nutraceuticals, and value-added products. However, low lipid yield is a significant impediment to its commercial viability. Genetic engineering can improve the fatty acid profile of algae without compromising its growth. This study introduced the diacylglycerol acyltransferase (BnDGAT) gene from Brassica napus into Chlorella sorokiniana-I, a fast-growing and thermotolerant natural strain isolated from wastewater, which increased its intracellular lipid accumulation. Hygromycin-resistant cells were selected, and enhanced green florescence protein fluorescence was used to distinguish pure transgenic cell lines from mixed cultures. Compared to the wild type, BnDGAT expression in transgenic C. sorokiniana-I caused a threefold increase in non-polar lipid and a twofold increase in polyunsaturated fatty acids. Nile red staining reaffirmed the presence of higher intracellular lipid bodies in transgenic cells. There was a substantial alteration in the fatty acid profile of transgenic alga expressing BnDGAT. The non-essential omega 9 (C18: 1) fatty acid decreased (5%–7% from 18%), while alpha-linolenic acid, an essential omega 3 fatty acid (C18: 3), was increased (23%–24% from 11%). This study substantiates a valuable strategy for enhancing essential omega-3 fatty acids and neutral lipids to improve its nutritional value for animal feed. The increased lipid productivity should reduce the cost of producing fatty acid methyl esters (FAME). Improved FAME quality should address the clouding issues in cold regions.  相似文献   

19.
Total lipids were extracted from 22 species of Malaysian fish and the constituent fatty acids were analysed by gas chromatography. Malaysian fish generally contained high levels of saturated fatty acids (range 36-55% total fatty acids) and contained variable amounts of monounsaturates, chiefly palmitic and stearic acids, but only trace levels of 20:1 and 22:1. Unlike fish caught in colder northern hemisphere waters, Malaysian fish were found to contain arachidonic acid (20:4 omega 6, range 2-12%) in addition to the expected eicosapentaenoic acid (20:5 omega 3, range 1-13%) and docosahexaenoic acid (22:6 omega 3, range 6.6-40.4%).  相似文献   

20.
Matured females of two Lake Baikal endemic fish species, Comephorus baicalensis and Comephorus dybowski, have been investigated for lipid of the whole body and specific tissues (liver, muscles, ovaries), phospholipid classes and fatty acids of neutral and polar lipids. Total lipid in the body (38.9% fresh weight), liver (23.5%) and muscles (14.5%) of C. baicalensis were greater than those of C. dybowski (4.7, 8.7 and 2.6%, respectively); only their ovaries were similar (5.3 and 5.6% lipid, respectively). In both species, phosphatidylcholine and phosphatidylethanolamine were the major phospholipids, ranging from 60.7 to 75.1% of total phospholipid and 14.5–25.7%, respectively. In most cases, monounsaturated fatty acids (MUFA) were the major fatty acid group in C. baicalensis, whereas polyunsaturated fatty acids (PUFA) were the major group in C. dybowski. The MUFA 18:1(n-9) prevailed over other fatty acids in C. baicalensis and varied from 19% in polar lipids of muscles to 56.1% in neutral lipids of muscles. In polar lipid of C. dybowski, the PUFA 22:6(n-3) prevailed over other fatty acids in muscles and ovaries, while 16:0 dominated polar liver lipids and neutral lipids of all tissues. Other major fatty acids included 16:1(n-7), 18:1(n-7), and 20:5(n-3). Values of the (n-3)/(n-6) fatty acid ratio for neutral lipids of C. baicalensis (0.5–0.9) are well below the range of values characteristic either for marine or freshwater fish, while these values for polar lipids (1.6–1.8) are in the range typical of freshwater fish. Neutral lipid fatty acid ratios in C. dybowski (2.5–3.1) allow it to be assigned to freshwater fish, but polar lipids (2.8–3.7) leave it intermediary between freshwater and marine fish.  相似文献   

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