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1.
The fatty acid compositions of sterol esters from 4 citrus species, viz, orange. grapefruit, lemon and lime, were determined by GLC. Each species possessed its own intrinsic fatty acid pattern which could be used to differentiate it from the other species. In most cases varieties within a species had fatty acid patterns which could be used for varietal differentiation. In all citrus tested except Columbia lime, the major acid was linoleic acid; this acid varied from 10 to 56% of the total acid content. The ratios of 16/16:1 were distinct for each citrus species. The C22-C29 fatty acids were prevalent in citrus sterol esters ranging from 6·5% for some orange and grapefruit varieties to over 41% for two lime varieties. In all varieties C24 was the most prominent of these longer chain fatty acids. Argentation TLC indicated that these longer chain fatty acids primarily were esterified to dimethyl sterols. ft*|One of the laboratories of the Southern Region, Agricultural Research Service, U.S. Department of Agriculture.  相似文献   

2.
Vesicular lipids of 24 citrus cultivars were extracted and purified, and the esterified sterol glucosides (ESG) separated from other vesicular lipids by chromatography. Fatty acids of the ESG were analysed by gas-liquid chromatography as their methyl esters. Statistical analysis showed that five out of six citrus species or biotypes could be differentiated from each other on the basis of profiles of the five major ESG fatty acids. Differences between midand late-season sweet orange cultivers were detected. Small differences were observed between white- and red-fleshed grapefruit cultivars. Profiles of the minor acids showed higher relative percentages of iso-branched fatty acids in lemons and limes, and higher relative percentages of 12: 0 and 14: 0 fatty acids in mandarin and mandarin hybrids than in other cultivars.  相似文献   

3.
Barthet VJ 《Phytochemistry》2008,69(2):411-417
cis-Vaccenic acid or cis-11-octadecenoic acid, a C18:1 (n-7) isomer of oleic acid (C18:1 (n-9)) has been found in several oilseeds. It is synthesized from palmitic acid (C16:0) via production of C16:1 (n-7) by a Delta9 desaturase and elongation by an elongase giving C18:1 (n-7). In this study, the fatty acid composition of 12 Brassica species was analyzed by GC-FID and confirmed by GC-MS. All species contained C18:1 (n-7), C20:1 (n-7) and C22:1 (n-7) fatty acid isomers, suggesting that C18:1 (n-7) was elongated. The levels of these fatty acids varied according to the species. C18:1(n-7)) represented from 0.4% to 3.3% of the total relative fatty acid contents of the seeds. The contents of C20:1(n-7) and C22:1(n-7) levels were lower than C18:1(n-7) contents; the relative fatty acid composition varied from 0.02% to 1.3% and from below the limit of detection to 1.3% for C20:1 (n-7) and C22:1 (n-7), respectively. The ratios of (n-7)/(n-9) ranged from 2.8% to 16.7%, 0.6% to 29.5% and 0% to 2.6% for C18:1, C20:1 and C22:2, respectively. Using statistical similarities or differences of the C18:1 (n-7)/(n-9) ratios for chemotaxonomy, the surveyed species could be arranged into three groups. The first group would include Brassica napus, B. rapa, and B. tournefortii with Eruca sativa branching only related to B. napus. The second group would include B. tournefortii, Raphanus sativus and Sinapis alba. The last group would include B. juncea, B. carinata and B. nigra with no similarity/relationship between them and between the other species. Results suggested that the level of C20:1 (n-7) influenced the levels of all monounsaturated fatty acids with chain length higher than 20 carbons. On the other hand, palmitoleic acid (C16:1) levels, C16:1 being the parent of all (n-7) fatty acids, had no statistically significant correlation with the content of any of the fatty acids of the (n-7) or (n-9) family.  相似文献   

4.
Oranges and lemons: clues to the taxonomy of Citrus from molecular markers   总被引:4,自引:0,他引:4  
Go into any grocery store and one is confronted with an array of Citrus fruit: oranges, grapefruit, mandarins (tangerines), lemons and limes. This is rich bounty for the shopper, but taxonomists are perplexed as to how to classify the various kinds of Citrus that have existed since antiquity. Now, thanks to new genetic and molecular biological techniques, the relationships between these fruit are being unraveled and show that there are probably only three true species.  相似文献   

5.
Total fatty acids derived from 12 species of mushrooms were separated into fatty acid and 2-hydroxy fatty acid fractions (FA and HFA), and analyzed quantitatively. The HFA content varied from 0 to 22% of total fatty acids. The major fatty acids were 16:0, 18:0, 18:1, 18:2, and the major 2-hydroxy fatty acids were h16:0, h18:0, h22:0, h24:0. The predominant HFA in the mushrooms investigated had chain-lengths greater than 20 C-atoms, and were derived from sphingolipids — ceramides and cerebrosides.  相似文献   

6.
The lipids from the electric organ of the ray, Torpedo marmorata, have been isolated and characterized. The major lipids were cholesterol, choline phospholipids, ethanolamine phospholipids, and sphingomyelins. The major fatty acids of ethanolamine phospholipids were 18:1, 18:0, 22:6, and 20:4. More than 50% of the acids in choline phospholipids were 16:0. The sphingomyelins consisted of five major ceramide species, all with sphingosine and the fatty acids 14:0, 15:0, 16:0, 22:1, and 24:1. The fatty acid 15:0 was mostly branched (n-2), a fatty acid earlier identified in sphingomyelins of the rectal gland of spiny dogfish. All long-chain bases were dihydroxy bases with a small percentage of branched chains. Sulfatides (cerebroside sulfate) made up the largest glycolipid fraction. The polar moiety wase galactose-3-sulfate. The fatty acids were normal and 2-hydroxy; the homologue 24:1 was the most abundant in both types of fatty acids. Most fatty acids were higher homologues of mono-unsaturated acids, but normal 18:0 fatty acid was also found. The long-chain bases were both dihydroxy and trihydroxy, with very small amounts of branched chains. The two major ceramide species of sulfatides were sphingosine combined with normal and hydroxy 24:1 fatty acids, respectively. Smaller amounts of trihydroxy base (18:0) were found linked to hydroxy 24:1 fatty acid, but not to its normal homologue. The cerebrosides contained the two major species mentioned above but lacked the trihydroxy base-hydroxy fatty acid species. The ratio of the activity of Na+-K+-dependent ATPase (EC 3.6.1.3) and the concentration of sulfatides was similar to ratios found for other tissues with normal and increased Na+ and K+ transporting capacity. The significance of this finding is discussed.  相似文献   

7.
The relationships among lemons, limes and citron: a chromosomal comparison   总被引:1,自引:0,他引:1  
Lemons, limes and citron constitute a group of closely related Citrus species, whose species delimitations and taxonomic relationships are unclear. In order to identify karyotypic similarities and species relationships within this group, the CMA+/DAPI- banding pattern and the distribution of the 5S and 45S rDNA sites of 10 accessions of lime, lemon, and citron were investigated. The four cultivars of C. limon analyzed showed the same pattern of CMA+ bands and rDNA sites, suggesting that they originated from a single germplasm, later differentiated by distinct somatic mutations. The lemons C. jambhiri, C. limonia and C. volkameriana displayed karyotypes very similar to each other, but they differed from C. limon by the absence of a single chromosome with one band in each telomere. The limes, C. aurantifolia and C. limettioides, seemed less related to each other and exhibited different heteromorphic chromosome pairs. In C. aurantifolia, the presence of a chromosome type unknown in all other Citrus species cytologically known so far supports the assumption that this accession may be derived from a hybrid with a species from the subgenus Papeda or from another genus. Citrus medica was the only homozygous accession of this group and all of its chromosome types were clearly represented in limes and lemons, some of them forming heteromorphic pairs. The analysis of the distribution of rDNA sites allowed a further refinement of the comparison among accessions. The lemons and limes were heterozygous for all rDNA sites, whereas C. medica was entirely homozygous. These data support the hypothesis that C. medica is a true species while the other nine accessions are hybrids.  相似文献   

8.
Fatty acid composition of lipids in various organs of the bonito (Euthynnus pelamis), a typical species within the tuna species, caught in the sea off the Pacific coast of Japan, was determined by gas-liquid chromatography. The major fatty acids of all organs examined were palmitic acid (16:0), palmitoleic acid (16:1), oleic acid (18:1), icosapentaenoic acid (20:5), and docosahexaenoic acid (22:6). 22:6 (DHA) was the dominant fatty acid accounting for 25% or more of the total fatty acids in all organs of the bonito, caught in the sea off the Japanese coast.  相似文献   

9.
Lipid composition was determined for hydrothermal vent species collected by the Deep Submergence Vehicle ALVIN from chimneys at 2,500 m depth on the East Pacific Rise. These are the first lipid biomarker studies for most of these species. Lipid content was low and dominated by polar lipid in the vestimentiferan tubeworm Riftia pachyptila, mussels Bathymodiolus sp. and limpets Lepetodrilus spp. The galatheid (Munidopsis subsquamosa) and most brachyuran adult (Bythograea thermydron) crabs were characterized by higher storage lipid (triacylglycerol). Total polyunsaturated fatty acids were similar in R. pachyptila plume and body, but higher in the posterior part of the soft body, which had more docosahexaenoic acid (2-5% of total FA) compared to the anterior and plume (< or =0.3%). Two sulphur-oxidizing bacterial markers, 16:1(n-7)c and 18:1(n-7)c, were high in R. pachyptila and mussel (up to 23%), but lower in both crab species (4-17%). R. pachyptila had greater nonmethylene interrupted diunsaturated fatty acids (8-13%) than all other species (2-8%). R. pachyptila may desaturate and elongate 18:1(n-7)c to obtain essential polyunsaturated fatty acids 20:5(n-3) and 20:4(n-6). The sterol composition of R. pachyptila included similar amounts of cholesterol and desmosterol, whereas the other species had a more diverse sterol composition. These differences in lipids, fatty acids and sterols reflect diverse nutritional strategies and possibly temperature regimes in these species.  相似文献   

10.
Profiles of cellular fatty acids of Erwinia herbicola, E. ananas, E. stewartü and E. uredovora , comprising the Herbicola group in the genus Erwinia , contained 7 major components accounting for 90–95% of total fatty acids, and,30 minor components, each less than 1% of the total. The major components and their average percentage ranges in cells on King's medium B at 28°C for 1 days were: 12:0 (3.5–4.5%), 14:0 (3.6–4.3%), 16:0 (28.1–35.7%), 16:1 (17.5–24.2%), 18:1 (13.9–31.9%), 3-OH 14:0 (4.6–7.2%) and cyclopropane 17:0 (trace levels in E. stewartii , 5.0–6.7% in other species). Fatty acid composition changed as a function of physiological age of the cells. The regression coefficient ( b ) as a function of age for percentage of saturated even- and oddcarbon, straight-chain fatty acids (Classes A and B) was either negative or not significant for E. ananas and positive for the other species. A series of dichotomous steps was constructed based on fatty acid algorithms to differentiate all four species.  相似文献   

11.
The lipid compositions of the gradient-purified gastric microsomal membranes from the fundic mucosa of pig, rabbit, and frog were determined. The total lipid content varied widely. Compared to the rabbit (21.6 ± 0.6 mg/100 mg protein), the pig had about twice as much and the frog about three times as much lipid. The levels of cholesterol were higher in both mammalian species (about 32% of the lipid) compared to frog (23%). Phospholipids accounted for about 45, 54, and 52% of the total microsomal lipids from pig, rabbit, and frog and the molar ratios of cholesterol to phospholipid in the three species were 1.95, 1.6, and 1.17, respectively. Phosphatidyl choline and phosphatidyl ethanolamine together constituted about 75% of the total phospholipids in pig and frog and 93% in rabbit gastric microsomes. Sphingomyelin comprised 19.3, 3.2, and 1.5% in pig, rabbit, and frog, respectively. Phosphatidyl inositol constituted 5, 2.7, and 23.6% in pig, rabbit, and frog, respectively. The ratios of phosphatidyl ethanolamine to phosphatidyl choline were 1.17, 1.1, and 0.85 in pig, rabbit, and frog, respectively. The saturated fatty acids 16:0 and 18:0 and the unsaturated fatty acid 18:1 and 18:2 were the predominant fatty acids in all phospholipids. The ratios of saturated to unsaturated fatty acids were between 0.8 and 0.9 in phosphatidyl choline and 0.27 and 0.5 in phosphatidyl ethanolamine from all three species. The contributions by saturated fatty acids were much more in phosphatidyl inositol and sphingomyelin than in phosphatidyl choline and phosphatidyl ethanolamine from all species. Position 1 of phosphatidyl choline had 63% saturated and 37% unsaturated fatty acids; while the reverse was true for position 2. Phosphatidyl ethanolamine, however, had 85% saturated fatty acids in position 1 compared to only 25% in position 2. Arachidonic acid (20:4) was present in significant amounts in all species located exclusively at position 2 of both phosphatidyl choline and phosphatidyl ethanolamine.  相似文献   

12.
The fatty acid compositions of stationary-phase cultures of Arizona arizonae, Citrobacter freundii, Providencia alcalifaciens, Providencia stuartii, and Providencia sp. were studied. The major fatty acids of A. arizonae, C. freundii, and Providencia were 16:0, 16:1, 17:cyclopropane, and 19:cyclopropane. The fatty acid compositions of the two strains of A. arizonae examined were similar to each other, but the three strains of C. freundii differed from one another in their fatty acid compositions. In both A. arizonae and C. freundii, the relative quantities of saturated, unsaturated, and cyclopropane fatty acids were similar to those which have been found in stationary-phase cultures of other members of the Enterobacteriaceae. The three strains of Providencia also differed from one another in their fatty acid compositions. In all three strains, the total quantity of unsaturated fatty acids was larger and that of the cyclopropane fatty acids was smaller than those found in stationary-phase cultures of other enteric bacteria.  相似文献   

13.
The fatty acid profiles of various organs of the thermogenic inflorescence of Sauromatum guttatum and of the sporophylls of thermogenic male cones of two cycad species (Encephalartos ferox and Dioon edule var edule and var angustifolium) were determined by gas chromatography. During anthesis, palmitate (16:0), oleate [18:1 (9)], cis-vaccinate [18:1 (11)], and linoleate [18:2 (9, 12)] were the most abundant fatty acids in the Sauromatum appendix. cis-Vaccinic acid, a positional isomer of oleic acid, was identified by comparing its retention time on a gas chromatography column and its mass spectrum to an authentic compound. The percentage of oleic acid from total fatty acids dropped from about 9 in the morning 3 d before heat production to 6 in the morning 2 d before heat production. At this time, the percentage of cis-vaccinic acid increased from 3 to 11%, and then remained at this level until the inflorescence dried and died. Palmitoleic acid [16:1 (9)], the common precursor of cis-vaccinic acid, is a minor component of total fatty acids. In six other organs of the Sauromatum inflorescence including thermogenic organs, such as male flowers and lower spadix, palmitate, oleate, and linoleate were prevalent but cis-vaccinate was not. The thermogenic male cones of the two cycad species were rich in palmitic, oleic, and linolenic acids. The level of cis-vaccinic acid in these organs was less than 0.5%.  相似文献   

14.
The fatty acid composition of the total lipids from two Conidiobolus species was studied by gas—liquid chromatography. The major fatty acids of C. lamprauges were palmitic acid (C16:0), oleic acid (C18:1), linolenic acid (C18:3), and arachidonic acid (C20:4). For C. eurymitus , myristic acid (C14:0), C16:0, and linoleic acid (C18:2) were the most abundant acids. The fatty acid composition of C. eurymitus was quite different from that of the Conidiobolus species as mentioned in other reports. The lipid composition of the total lipids of C. lamprauges and C. eurymitus was also studied by thinchrography on quartz rods. Triglycerides and phospholipids were the major components in the two Conidiobolus species.  相似文献   

15.
Lipid metabolism was investigated during the reproductive cycle of Labidura riparia (Pallas). The lipid classes and their constitutive fatty acids present in hemolymph and ovaries were measured using thin‐layer chromatography and gas‐liquid chromatography. In the hemolymph, total lipids increase steadily from the previtellogenic period to vitellogenic arrest. These lipids are predominantly diacylglycerols and phospholipids. In the ovaries, total lipids increase during vitellogenesis then decrease during the vitellogenesis arrest period. The major lipids are triacylglycerols, followed by phospholipids. In both hemolymph and ovaries, all lipid classes contained variable proportions of seven main fatty acids: the saturated fatty acids myristic acid (14:0), palmetic acid (16:0), and stearic acid (18:0); the monounsaturated fatty acids palmitoleic acid (16:1) and oleic acid (18:1); and the polyunsaturated fatty acids linoleic acid (18:2) and linolenic acid (18:3). Unsaturated fatty acids predominate throughout the reproductive cycle. The percentage compositions of total and triacylglycerol fatty acids do not change markedly during the reproductive cycle in hemolymph nor in ovaries, with 18:2, 18:1 and 16:0 fatty acids being the major components. However, for diacylglycerols and phospholipids, the proportions of fatty acids vary systematically. For phospholipids during the vitellogenesis period, 18:2 increases considerably whereas other fatty acids decrease; for diacylglycerols, these fatty acids vary in the reverse way.  相似文献   

16.
1. The total yield of fatty acids from the whole envelopes was markedly higher than that obtained from the ordinary cell walls. In both samples the major fatty acids were C(16) and C(18) acids. 2. The whole envelopes contained C(18) acids and long-chain (C(19)-C(26)) fatty acids, in a higher proportion than did the ordinary cell walls. Fifteen fatty acids with more than 18 carbon atoms were identified, among which 2-hydroxy-C(26:0) and C(26:0) acids predominated. 3. A complex sphingolipid containing inositol, phosphorus and mannose was isolated from the whole cell envelopes. The main fatty acids of this lipid were 2-hydroxy-C(26:0) and C(26:0) acids. It was concluded that this sphingolipid is present both in the ordinary cell wall and in the plasma membrane of baker's yeast. 4. The neutral lipids amounted to over 50% and the glycerophosphatides to about 30% of the total fatty acid content of the whole envelope. The major fatty acids in these lipids were C(16:1), C(18:1) and C(16:0) acids. The proportion of fatty acids with more than 18 carbon atoms was lowest in the neutral lipids, whereas the neutral glycolipids contained the highest percentage of these fatty acids. Acidic glycolipids amounted to 14% of the total fatty acid content of the whole envelope. The presence of a cerebroside sulphate in this lipid fraction was demonstrated, whereas the high content of 2-hydroxy-C(26:0) acid found is caused by the complex inositol- and mannose-containing sphingolipid.  相似文献   

17.
Total lipid and the fatty acid compositions of phospholipid and triacylglycerol fractions, prepared from eggs, 3rd instars of larvae, pupae, male and female adults of Lertha sheppardi, were analyzed by gas chromatography and gas chromatography-mass spectrometry. The effect of diet (adults’ nutrition) on fatty acid composition of L. sheppardi adults was also investigated. Total lipid of L. sheppardi considerably increased in adults compared with immature stages. There was a significant decrease in total lipid level in larval stage in contrast with egg stage. Qualitative analysis revealed the presence of 14 fatty acids during all stages. The major components were C16 and C18 saturated and unsaturated components which are ubiquitous to most animal species. In addition to these components, one odd-chain (C17:0) and prostaglandin precursor fatty acids were found. The fatty acid profiles of phospholipids and triacylglycerols were substantially different. In phospholipid fraction, monounsaturated fatty acids were the major proportion of fatty acids in both sex of adults and pupae, whereas polyunsaturated fatty acids were the most dominant fatty acids in eggs and 3rd instars. Results of triacylglycerol fraction revealed that fatty acid composition of eggs had higher level of C16:1, C18:0 and C18:3n-3 content than that of 3rd instars and pupae, which suggests accumulation of energetic and structural reserve materials during embryonic development. At more advanced developmental stages, mainly in adult females, the amount of C16:1 increased once again, which may be related to the need for accumulation of sufficient energy and of carbon reservoir in the developing new vitellum. Percentages of C18:1 were significantly high in adult stages compared to other stages. These findings indicate that the accumulation and consumption of fatty acids fluctuate through different development stages. Diet did not effect the fatty acid composition of L. sheppardi adults.  相似文献   

18.
The fatty acid compositions of neutral lipid, glycolipid and phospholipid fractions from ice algae sampled from the Barents Sea in spring and autumn were examined for seasonal differences. The ice-algal assemblages were dominated by diatoms. In spring, Nitzschia frigida was the most common species whereas resting stages of Thalassiosira bioculata and Actinocyclus cf curvatulus predominated in autumn. With the exception of one spring sample, neutral lipids predominated over glycolipids and phospholipids in all algal samples. The lipid fractions displayed characteristic fatty acid compositions. In the spring samples the major fatty acids of the neutral lipid fraction were 16:0, 16:1(n-7) and 20:5(n-3) whilst the glycolipid fraction was characterised by higher levels of 20:5(n-3) and C16 polyunsaturated fatty acids, particularly 16:4(n-1). Phospholipids contained higher levels of 22:6(n-3) than the other two lipid fractions although 20:5(n-3) was still the major polyunsaturated fatty acid. In the autumn samples, the neutral lipid fraction contained higher proportions of saturated fatty acids and 16:1(n-7) than the two polar lipid fractions and 22:6(n-3) was most abundant in phospholipids. As with the spring samples, 20:5(n-3) was the major polyunsaturated fatty acid in all lipid fractions of the autumn algae. Overall, the fatty acid compositions of the lipid fractions from spring and autumn algal samples were similar and are consistent with diatoms being the predominant group in the ice algae studied. The high level of neutral lipids observed in both spring and autumn samples suggests that the production of neutral lipids is characteristic of ice algae regardless of season. Nevertheless, some species-specific differences in lipid production may exist since the neutral lipid content of autumn samples containing mainly A. curvatulus was substantially higher than those in which T. bioculata predominated. Received: 26 September 1997 / Accepted: 12 January 1998  相似文献   

19.
The fatty acid composition of 10 species of estuarine phytoplankton was determined using gas-liquid chromatography. Nine of the species were isolated from Yaquina Bay, Oregon. These species were common components of the phytoplankton of the bay. The tenth species, Isochrysis galbana, was obtained from the Culture Collection of Algae at Indiana University. The 10 organisms comprised 3 species of Chlorophyta, 1 species of Cryptophyta, and 6 species of Chrysophyta. Twenty-eight fatty acids were found in the 10 species. The fatty acids common to all species were 14:0, 16:0, 16:1, 13:0, 18:1, and 18:2. The Chlorophyta were distinguished by a high content of linolenic acid, 18:3. The diatoms were distinguished by very low amounts of C18 acids and high proportion of 20:5. All species contained a high proportion of palmitic acid, 16:0.  相似文献   

20.
The genus Pectinatus is currently composed by two species, Pectinatus cerevisiiphilus and Pectinatus frisingensis , both asociated with beer spoilage. This study describes a novel isolate (strain B6) retrieved from a wastewater treatment plant collecting residues from a large number of wineries. Based on similarity analysis of 16S rRNA gene sequences, strain B6 belongs to the genus Pectinatus . Strain B6 is a strict anaerobe like other Pectinatus species and it presents non-motile, coccoid cells showing a slight oval shape. Strain B6 shows marked physiological differences with other Pectinatus species both in fatty acid composition and carbon source utilization. The most abundant fatty acids found in strain B6 were 18:1 (42.8%) and 16:0 (18.3%) representing a total of over 61% of fatty acids in this microorganism while these fatty acids represented 41.3% in P. cerevisiiphilusT and 2.4% in P. frisingensisT of their total. Fatty acid 15:0 was not significant in strain B6 and represented 28.6% and 13.3% for P. cerevisiiphilusT and P. frisingensisT, respectively. Strain B6 showed a faster growth rate and higher optimum temperature than its relatives P. cerevisiiphilus and P. frisingensis . Strain B6, P. cerevisiiphilus and P. frisingensis could be clearly differentiated by acid production tests from substrates such as esculine and gluconate, and the lack of acid production from rhamnose and fucose among others. G+C mol% content in strain B6 is 36.5%. Based on genotypic and phenotypic differences, strain B6 is proposed as a novel Pectinatus species, P. portalensis nov. sp. Both strain B6 and the two described species of Pectinatus grow on beers and wines. These results provide insights about the origin and reservoirs of Pectinatus species and spoiling alcoholic beverages.  相似文献   

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