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1.
Photosynthetic carboxylating enzymes and the effects of light and temperature on 14CO2 efflux in two species of gymnosperm leaves were studied. The activity of RuBP carboxylase was high and that of PEP carboxylase was very low when compared to C4 plants. The CO2 compensation point was high. 14CO2 efflux was greater in light than in darkness and the ratio (L/D) increased with increase in temperature and light intensity. The inhibitors of glycolate metabolism showed decreased 14CO2 evolution in light while dark respiration was unaffected. It is concluded that both Cycas circinalis, L. and Cycas beddomei Dyer are C3 plants. 相似文献
2.
Roman A. Sidorov Anatoly V. Zhukov Vasily P. Pchelkin Andrei G. Vereshchagin Vladimir D. Tsydendambaev 《化学与生物多样性》2013,10(6):976-988
Small amounts of a mixture of fatty acid short‐chain‐alkyl esters (FASCAEs) were obtained from the fruits of twelve plant species of Celastraceae family, and in five of them the FASCAEs were present not only in the arils but also in the seeds. These mixtures contained 32 individual FASCAE species, which formed four separate fractions, viz. FA methyl, ethyl, isopropyl, and butyl esters (FAMEs, FAEEs, FAIPEs, and FABEs, resp.). The FASCAE acyl components included the residues of 16 individual C14–C24 saturated, mono‐, di‐, and trienoic FAs. Linoleic, oleic, and palmitic acids, and, in some cases, also α‐linolenic acid predominated in FAMEs and FAEEs, while myristic acid was predominant in FAIPEs. It can be suggested that, in the fruit arils of some plant species, FAMEs and FAEEs were formed at the expense of a same FA pool characteristic of a given species and were strongly different from FAIPEs and FABEs esters regarding the mechanism of their biosynthesis. However, as a whole, the qualitative and quantitative composition of various FASCAE fractions, as well as their FA composition, varied considerably depending on various factors. Therefore, separate FASCAE fractions seem to be synthesized from different FA pools other than those used for triacylglycerol formation. 相似文献
3.
Field grown leaves of sugar beet contained 0.89% of their fresh weight as chloroform : methanol 1 :2 extractable material, whereas climate chamber grown material contained 0.34, 0.15, and 0.16% in leaves, stalks, and roots respectively. A striking feature was the high proportion of sulfolipid: 7% of the total extractable of the field grown leaves, 19.5, 28.0, and 37.0% of the total extractable of respectively leaves, stalks, and roots from the climate chamber grown material. Among the fatty acids, all chain lengths from C12 to C28 were found, except only C17 and C19—Exceptionally high contents of fatty acids with a chain length of C26 or C28 were noted in some cases. The 2500–20,000 g fraction of root homogenates contained 19% of the total root lipids. Almost all of the phosphatidyl choline and about half of the phosphatidyl ethanolamine, but only 5% of the sulfolipid followed the fraction. A fractionation of conjugate lipid types was evident, with a loss of 18/2 and 18/3 conjugates, and with an increase in the proportions of 16/0 and, possibly, of the long-chain (around C26) conjugates. The unspecific ATPase activity of the 2500–20,000 g fraction was rendered specific for (Na++ K+) stimulation by treatment with 0.1% deoxycholate for 1 hour. This induced a more than 2-fold swelling of the preparation. About half of its total lipids were lost. Again, this loss was a fractional one, so that the phosphatidyl choline lost its long-chain (about C26) fatty acid conjugate while the short to medium length chain conjugates remained; whereas the reverse was the case with the sulfolipid. The ATPase activity of the 2500–20,000 g fraction was destroyed by a 24 hour treatment with deoxycholate. As compared with the 1 hour treatment, the preparation lost about 20% both of its volume and of its chloroform : methanol extractable material. The quantitatively dominating loss was found in the (pigment + neutral fat) fraction. The monogalactosyl diglyceride, the phosphatidyl inositol, and a strongly acidic unknown fraction survived the deoxycholate treatments comparatively well. In the sulfolipid the fractionating effect of the prolonged deoxycholate treatment expressed itself as a loss mainly from the long-chain (about C26) fatty acid conjugate. The (Na++ K+) stimulation of the ATPase function of the particulate preparation is thus correlated with the balance between the long-chain (about C26) fatty acid conjugates of zwitterionic phosphatidyl choline and anionic sulfolipid. This is of theoretical interest, since it indicates that the specific lipid composition under appropriate conditions may influence the charge and conformation of a lipoprotein complex, thereby determining its functional capacities. 相似文献
4.
Lipid composition and hydrocarbon structure of two colonial green algae of the genus Botryococcus, i.e., a museum strain and a field sample collected for the first time from Lake Shira (Khakasia, Siberia), have been compared. Polar lipids, diacylglycerols, alcohols, triacylglycerols, sterols, sterol esters, free fatty acids and hydrocarbons have been identified among lipids in the laboratory culture. The dominant fraction in the museum strain was formed by polar lipids (up to 50% of the lipids) made up of fatty acids from C12 to C24. Palmitic, oleic, C16 - C18 dienoic and trienoic acids were the main fatty acids of the museum strain. Aliphatic hydrocarbons were found in the lipid of the museum strain. However, these amounted maximally to about 1% of the dry biomass at the end of exponential growth phase. The qualitative and quantitative compositions of FAs and hydrocarbons of the museum strain of Botryococcus, (registered at the Cambridge collection as Botryococcus braunii Kutz No LB 807/1 Droop 1950 H-252) differed from those of the Botryococcus strain described in the literature as Botryococcus braunii. The Botryococcus sp. found in Lake Shira is characterized by a higher lipid content (<40% of the dry weight). Polar lipids, sterols, triacylglycerols, free fatty acids and hydrocarbons have been identified among lipids in the field sample. The main lipids in this sample were dienes and trienes (hydrocarbons <60% of total lipid). Monounsaturated and very long chain monounsaturated fatty acids, including C28:1 and C32:1 acids, were identified in the Botryococcus found in Lake Shira. The chemo-taxonomic criteria allow us to unequivocally characterize the organism collected from Lake Shira as Botryococcus braunii, race A. 相似文献
5.
T. V. Ivanova N. A. Myasoedov V. P. Pchelkin V. D. Tsydendambaev A. G. Vereshchagin 《Russian Journal of Plant Physiology》2009,56(6):787-794
Qualitative and quantitative compositions of esterified fatty acids (FAs) in the total lipids from the leaves, shoots, and
roots of halophile plants, such as suaeda (Suaeda altissima), samphire (Salicornia europaea), and wormwood (Artemisia lerchiana), collected in their natural environments were estimated by GLC techniques. It was shown that the vegetative organs of these
halophytes contained 24 FA species, and 16 of them were tentatively identified as the very-long-chain FAs (VLCFAs). There
were four VLCFA groups, viz. C20, C21, C22, and C23, each including saturated, mono-, and diunsaturated components; C24 and C25 FAs were also present. The concentration of VLCFAs in the total FAs comprised 4–64%. In vegetative organs of higher plants
not subjected to genetic transformation, such a high VLCFA content was found for the first time. Saturated and even-numbered
components predominated among the VLCFAs, and the roots exceeded severalfold the above-ground organs in the total VLCFA content.
Possible pathways of VLCFA biosynthesis in plants, VLCFA content in the vegetative tissues, and the physiological role of
membrane lipid FA composition in the plant salt metabolism are discussed. 相似文献
6.
Stefan Schouten Adam M. Klimiuk Marcel T. J. van der Meer Jaap S. Sinninghe Damsté 《Geomicrobiology journal》2013,30(3):179-188
Green nonsulfur-like bacteria (GNSLB) in Yellowstone hot spring microbial mats have been extensively studied and are thought to operate both as photoheterotrophs and photoautotrophs. Here we studied the occurrence and carbon metabolisms of GNSLB by analyzing the distribution and isotopic composition of their characteristic wax ester lipids in four Californian and Nevada hot spring microbial mats at a range of temperatures (37–96°C). The distribution of wax esters varied strongly with temperature. At temperatures between 50–60°C the wax ester composition in each of the four hot spring microbial mats was dominated by C30 to C36 wax esters, consisting of mixtures of C15-C18 n-alkyl and branched fatty acids and alcohols, typical for GNSLB. Stable carbon isotopic analysis showed that these wax esters were only depleted by 5 to 10‰ compared to dissolved inorganic carbon in the overlying water, suggesting that these GNSLB were mainly autotrophic. However, analysis of different depth layers of one microbial mat showed that these GNSLB wax esters were increasingly depleted in 13C with depth, suggesting that photoautotrophy mainly occurred in the top layer of the mat. 13C-depleted C36-C44 wax esters were found in one hot spring at high temperatures (77–96°C) and are likely derived from allochtonous plant waxes. At several lower temperature sites (35–40°C) the wax esters were predominantly composed of C28, C30 and C32 wax esters consisting of mixtures of C14-C16 fatty acids and n-alkanols and were depleted in 13C by 15–20‰ relative to dissolved inorganic carbon, suggesting they may be derived from heterotrophic organisms. Our results indicate that autotrophic GNSLB occur widely in hot springs and that diverse groups of organisms contribute to the pool of wax ester lipids in hot spring environments. 相似文献
7.
Wax esters, which are esters of fatty alcohols and fatty acids (FAs), are one of the main classes of reserve lipids in all coral species. The chemical structures and the content of wax ester molecular species were determined for the first time in nine coral species from three taxonomic groups: symbiotic reef-building corals, (Hexacorallia subclasses), symbiotic soft coral alcyonarians, and asymbiotic soft coral gorgonians (Octocorallia subclasses) collected in the South China Sea (Vietnam). Our comparison of these groups showed that the absence of symbiotic microalgae (zooxanthellae) and the exoskeleton affects the profile of molecular species of wax esters considerably. The main components of wax esters of all corals were cetyl palmitate (16:0-16:0) and other saturated wax esters containing 30, 34, and 36 carbon atoms. The content of unsaturated molecular species 6:0–16:1, 16:0–18:1, and 16:0–20:1 in wax esters of symbiotic soft corals (alcyonarians) was greater than that in wax esters of reef-building corals. In contrast to symbiotic coral species, wax esters of asymbiotic soft corals, namely azooxanthellate gorgonians, contained a considerable amount of long-chain molecular species (C37-C41) with an odd number of carbon atoms. The presence of such molecular species indicates that asymbiotic gorgonians may use bacterial FAs in biosynthesis of their own wax esters. This observation confirms our hypothesis that bacterial community is important for maintaining the energy balance of azooxanthellate corals. 相似文献
8.
The homologous series of n-alkyl esters (C1–C10) of 3,4-dichlorobenzoic acid was synthesized and their effects in inhibiting the growth of Nicotiana meristems were studied. The inhibition of growth was considered in terms of penetration of chemicals into the plant tissue and subsequent cell membrane disruption. Penetration was investigated by applying the emulsified ester to the meristem and then measuring the compound recovered with the isolated surface lipids. Decreasing amounts of 3,4-dichlorobenzoate esters penetrated into the plant as the alkyl chain length of the ester moeity was increased. Essentially no penetration occurred with the n-C7 through C10 esters tested. The effect of the ester homologues on cell membranes was studied by measuring the efflux of betacyanin from beet root cells. Decreasing amounts of pigments were released as the alkyl chain length of the ester was increased. Minimal cell membrane disruption was found for the C7–C10 esters. Inhibition of the plant meristem may result from the more rapid penetration of the short chain ester homologues into the plant. 相似文献
9.
- Endomycopsis vernalis was cultivated on media with different N supply: series A 1%, series B 0,125% asparagine. Sonified cells were extracted and yielded 14.3% (A) and 65.3 (B) total lipids/non lipid dry matter respectively.
- Neutral and complex lipids were separated by rubber membrane dialysis. There is no difference in the percentage of complex lipids of both series. The increase of lipids in cells grown on low N level is due to a higher content of neutral lipids.
- Components of the neutral lipids, analysed by DC, were diglycerides, triglycerides, free and esterified ergosterol. Their percentage is influenced by the nutritional conditions. There is a significant increase of triglycerides and of sterol esters in the high lipid cells of series B.
- Methyl esters of component fatty acids of glycerides and sterol esters were analyzed by GLC. Saturated acids C14, C15, C16, C17, C18, monoenic acids C16 and C18, linoleic and linolenic acids were found to be present. Major acids were in all cases 18:1 (17–57%), 18:2 (18–50%) and 16:0 (10–18%). Linolenic acid is higher in di-and triglycerides of low lipid cells of series A than in high lipid cells of series B. Both qualitative and quantitative differences of fatty acids were found in sterol esters of series A and B respectively.
- The major components of complex lipids, identified by DC and isolated by CC, in both series, were phosphatidyl choline (A:36.5, B:41.0%) and phosphatidyl ethanolamine (A:24.9, B:20.5%) in addition to small amounts of lysophosphatidyl choline, lysophosphatidyl ethanolamine, phosphatidyl serine, monophosphoinositide, diphosphatidyl glycerol and, possibly cerebroside like substances.
- Methyl esters of the fatty acids of phosphatidyl choline and ethanolamine from both series were determined by GLC. In all samples 16:0, 18:0, 18:1, 18:2 and 18:3 acids were present besides of traces of 16:1 and 17:0. In contrast to neutral lipids the major acid of phospholipids is linoleic (53–58%), followed by oleic (8–24%) and linolenic acid (1–18%). The percentages of palmitic (4–8%) and stearic acids (tr.-1%) are small. Low lipid cells of series A differ from high lipid cells of series B by an increase of linolenic, and a decrease of linoleic acids, both in phosphatidyl choline and phosphatidyl ethanolamine.
10.
Calanus glacialis is a key herbivore in Arctic shelf seas. It feeds on primary producers and accumulates large energy reserves, primarily as
wax esters. Lipid classes, fatty acids (FAs) and fatty alcohols (FAlcs) from copepodite stage II (CII) to adult females (AF)
from Kongsfjorden, Svalbard, were studied in May 2004. Wax esters were the dominating lipid class in all stages, ranging from
34% of total lipids in CII to 60% in CIII–CV. Triacylglycerols increased from 8% of total lipids in CII to 23% in AF. In the
earlier stages, 16:1n7 and 16:0 FAs and FAlcs were the major components of the neutral lipids, whereas the later stages were
mainly characterized by the long-chained FAs and FAlcs 20:1n9 and 22:1n11. C. glacialis utilizes the short spring bloom to build up lipid reserves, mainly as wax esters, and it also incorporates effectively essential
polyunsaturated FAs such as 20:5n3 and 22:6n3 in its polar lipids. 相似文献
11.
V. N. Popov O. V. Antipina V. P. Pchelkin V. D. Tsydendambaev 《Russian Journal of Plant Physiology》2012,59(2):177-182
Changes in the fatty acid (FA) composition of leaf and root lipids of heat-loving tobacco (Nicotiana tabacum L., cv. Samsun) plants during low-temperature hardening (8°C for 6 days) were studied. Hardening could improve leaf but not
root cold tolerance. As this took place, the relative content of polyunsaturated (18:2n-6 and 18:3n-3) FAs increased and the
proportion of saturated and monounsaturated FAs decreased. In contrast, in the roots hardening slightly increased the concentration
of saturated FAs (16:0 and 18:0) and reduced the level of unsaturated FAs (18:1n-9, 18:2n-6, and 18:3n-3). At the same time,
root lipids contained much C20–24 FAs, and their content increased during hardening. It was suggested that an increased FA saturation and elevated proportion
of C20–24 FAs in the root lipids resulting in the lower membrane fluidity could be a reason for incapability of heat-loving tobacco
plant roots of hardening and plant death at the lowtemperature stress. 相似文献
12.
Zhukov A. V. Lebedeva N. I. Vereshchagin A. G. 《Russian Journal of Plant Physiology》2001,48(2):181-189
The changes of the molecular species composition of esterified fatty acids (FAs) of total and nonextractable lipids were determined in roots and etiolated shoots of 3- to 10-day-old wheat (Triticum aestivumL.) seedlings infected with the fungus Bipolaris sorokiniana, the agent of helminthosporic root rot. A novel technique of assessing the extent of the infection-induced deviation of FA composition, mol %, from the control value was developed. It consists in the quantitative determination of both the deviations in this composition and the extent of contribution of separate FA species to the deviations observed. The application of this technique has shown that, for the total lipids, the maximum of such a deviation, in accordance with the membrane theory of stress, directly coincided in time with the onset of a decrease in the dry matter content in both roots and shoots. In each of these, the deviation was primarily caused by the change in the content of those FA species that usually dominate in a specific group of membrane lipids prevailing in a given organ, viz., plastid glycolipids in shoots and extraplastidal membrane phospholipids in roots. In both cases, C20–C22FAs significantly contributed to the deviations observed. This fact seems to reflect an enhanced formation of epicuticular waxes rich in these FAs on the shoot and root surfaces as an adaptive response of plants to fungal infection. Nonextractable (annular) membrane lipids, because of their vital importance for the survival of plant cells, differed from the total lipids with a far greater stability of their quantitative FA composition under conditions of infection-induced metabolic disturbances. 相似文献
13.
Interactive effects of elevated CO2 and nitrogen deposition on fatty acid molecular and isotope composition of above‐ and belowground tree biomass and forest soil fractions
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Marco Griepentrog Timothy I. Eglinton Frank Hagedorn Michael W. I. Schmidt Guido L. B. Wiesenberg 《Global Change Biology》2015,21(1):473-486
Atmospheric carbon dioxide (CO2) and reactive nitrogen (N) concentrations have been increasing due to human activities and impact the global carbon (C) cycle by affecting plant photosynthesis and decomposition processes in soil. Large amounts of C are stored in plants and soils, but the mechanisms behind the stabilization of plant‐ and microbial‐derived organic matter (OM) in soils are still under debate and it is not clear how N deposition affects soil OM dynamics. Here, we studied the effects of 4 years of elevated (13C‐depleted) CO2 and N deposition in forest ecosystems established in open‐top chambers on composition and turnover of fatty acids (FAs) in plants and soils. FAs served as biomarkers for plant‐ and microbial‐derived OM in soil density fractions. We analyzed above‐ and belowground plant biomass of beech and spruce trees as well as soil density fractions for the total organic C and FA molecular and isotope (δ13C) composition. FAs did not accumulate relative to total organic C in fine mineral fractions, showing that FAs are not effectively stabilized by association with soil minerals. The δ13C values of FAs in plant biomass increased under high N deposition. However, the N effect was only apparent under elevated CO2 suggesting a N limitation of the system. In soil fractions, only isotope compositions of short‐chain FAs (C16+18) were affected. Fractions of ‘new’ (experimental‐derived) FAs were calculated using isotope depletion in elevated CO2 plots and decreased from free light to fine mineral fractions. ‘New’ FAs were higher in short‐chain compared to long‐chain FAs (C20?30), indicating a faster turnover of short‐chain compared to long‐chain FAs. Increased N deposition did not significantly affect the quantity of ‘new’ FAs in soil fractions, but showed a tendency of increased amounts of ‘old’ (pre‐experimental) C suggesting that decomposition of ‘old’ C is retarded by high N inputs. 相似文献
14.
D. A. Demidkova 《Russian Journal of Marine Biology》2010,36(4):300-304
This study examines the composition of lipids, fatty acids, and fatty aldehydes in two marine bryozoan species, Berenicea meandrina and Dendrobeania flustroides, from the Sea of Okhotsk. The share of neutral lipids was up to 57.3% in D. flustroides and 54.9% in B. meandrina; the share of polar lipids was 33.2 and 40.4%, respectively. In all, 57 fatty acids (FA) and 9 aldehydes were identified
in total lipids. The main FAs were 16:0, 18:0, 22:6n-3, and 20:5n-3. The content of branched saturated FA in bryozoans was
on the average 6.4%. Three isomers of 16:1 (n-9, n-7, and n-5), five isomers of 18:1 (n-13, n-11, n-9, n-7, and n-5), four
isomers of 20:1 (n-13, n-11, n-9, and n-7), as well as 22:1n-9 and 22:1n-13 were found; the presence of 7-methyl-6-hexadienoic
acid (on the average, 3.0% of total FAs) was demonstrated. Non-methylene-inter-rupted FAs contributed 8.9 and 1.6% of the
total FAs in D. flustroides and B. meandrina, respectively, and were identified as 20:2(5,11), 20:2(7,13), 20:3(5,11,14), 22:2(7,13), and 22:2(7,15). In B. meandrina, minor amounts of 24:0, 24:1, 25:0, 26:0, 24:4n-3, 26:3(5,9,19), and 28:3(5,9,19) were found, suggesting sponge biofouling
on some bryozoan colonies. Aldehydes (branched saturated and unsaturated C16–19 homologues) did not exceed 10.3 and 1.9% of the total FAs in D. flustroides and B. meandrina, respectively. The presence of the FA markers that are characteristic of microalgae, protozoans, and detritus in bryozoan
lipids agrees well with data on polytrophic feeding of these bryozoans. 相似文献
15.
R. E. Summons L. R. Bird A. L. Gillespie S. B. Pruss M. Roberts A. L. Sessions 《Geobiology》2013,11(5):420-436
Ooids are one of the common constituents of ancient carbonate rocks, yet the role that microbial communities may or may not play in their formation remains unresolved. To search for evidence of microbial activity in modern and Holocene ooids, samples collected from intertidal waters, beaches and outcrops in the Bahamas and in Shark Bay in Western Australia were examined for their contents of lipid biomarkers. Modern samples from Cat and Andros islands in the Bahamas and from Carbla Beach in Hamelin Pool, Western Australia, showed abundant and notably similar distributions of hydrocarbons, fatty acids (FAs) and alcohols. A large fraction of these lipids were bound into the carbonate matrix and only released on acid dissolution, which suggests that these lipids were being incorporated continuously during ooid growth. The distributions of hydrocarbons, and their disparate carbon isotopic signatures, were consistent with mixed input from cyanobacteria together with small and variable amounts of vascular plant leaf wax [C27–C35; δ13C ?25 to ?32‰Vienna Pee Dee Belemnite (VPDB)]. The FAs comprised a complex mixture of C12–C18 normal and branched short‐chain compounds with the predominant straight‐chain components attributable to bacteria and/or cyanobacteria. Branched FA, especially 10‐MeC16 and 10‐MeC17, together with the prevalence of elemental sulfur in the extracts, indicate an origin from sulfate‐reducing bacteria. The iso‐ and anteiso‐FA were quite variable in their 13C contents suggesting that they come from organisms with diverse physiologies. Hydrogen isotopic compositions provide further insight into this issue. FAs in each sample show disparate δD values consistent with inputs from autotrophs and heterotrophs. The most enigmatic lipid assemblage is an homologous series of long‐chain (C24–C32) FA with pronounced even carbon number preference. Typically, such long‐chain FA are thought to come from land plant leaf wax, but in this case, their 13C‐enriched isotopic signatures compared to co‐occurring n‐alkanes (e.g., Hamelin Pool TLE FA C24–C32; δ13C ?20 to ?24.2‰ VPDB; TLE n‐alkanes δ13C ?24.1 to ?26.2 ?‰VPDB) indicate a microbial origin, possibly sulfate‐reducing bacteria. Lastly, we identified homohopanoic acid and bishomohopanol as the primary degradation products of bacterial hopanoids. The distributions of lipids isolated from Holocene oolites from the Rice Bay Formation of Cat Island, Bahamas were very similar to the beach ooids described above and, in total, these modern and fossil biomarker data lead us to hypothesize that ooids are colonized by a defined microbial community and that these microbes possibly mediate calcification. 相似文献
16.
I. V. Zhigacheva E. B. Burlakova T. A. Misharina M. B. Terenina N. I. Krikunova I. P. Generosova A. G. Shugaev S. G. Fattakhov 《Russian Journal of Plant Physiology》2013,60(2):212-220
The impacts of water deficit and melamine salt of bis(oximethyl)phosphonic acid (melaphen) on the fatty acid (FA) composition of membrane lipids and energy metabolism in mitochondria of 5-day-old pea (Pisum sativum L., cv. Flora-2) seedlings were studied. Insufficient watering resulted in the accumulation of saturated and a decrease in the content of unsaturated FAs with 18 and 20 carbon atoms. Seed treatment with 3 × 10?10 M melaphen prevented these changes in the FA composition in the mitochondrial membrane lipids. Changes in the FA compositions of membrane lipids were correlated with changes in energy metabolism in mitochondria: the efficiency of oxidative phosphorylation and the rate of NAD-dependent substrate oxidation in the presence of ADP and FCCP (carbonyl cyanide-p-trifluoromethoxyphenylhydrazone) were reduced. A close correlation was observed between changes in the highest rates of NAD-dependent substrate oxidation and the relative content of FAs with 18 (r = 0.76489) and 20 (r = 0.9637) carbon atoms. The regulatory role of C18 and C20 unsaturated FAs in the mitochondrial energy metabolism of pea seedlings is discussed. 相似文献
17.
S. P. Makarenko Yu. M. Konstantinov V. N. Shmakov T. A. Konenkina 《Russian Journal of Plant Physiology》2010,57(5):739-743
The fatty acid (FA) composition of callus lipids in two pine species, Pinus sibirica Du Tour and P. sylvestris L. was studied. Callus lipids were characterized by a high content of unsaturated FAs: 81.7% in P. sibirica and 63.2% in P. sylvestris. Among them, oleic and linoleic acids predominated (22.9 and 34.0% of total FAs in P. sibirica and 17.6 and 27.8% in P. sylvestris, respectively). Callus lipids also contained Δ5-UPIFA (unsaturated polymethyle-interrupted FAs), where pinoleic and sciadonic
acids predominated. A comparison of FAs in the lipids of P. sylvestris calluses derived from needle and needle photosynthesizing tissues of this pine species showed that callus lipids were characterized
by a greater diversity of Δ5-UPIFA but a lower degree of FA unsaturation and he higher level of Δ5-UPIFA. 相似文献
18.
Wax esters from the epicuticular wax of juvenile and mature-tree Pinus radiata foliage have been shown by capillary column GC-MS to consist mainly of short chain (C6–C12)alkanols esterified with long chain acids (C24–C32) and long chain alkanols (C24–C32) esterified with short chain acids (C6-C14) in a non-random manner. Mature-tree foliage wax esters also contained nonacosan-10-ol esterified with dodecanoic and tetradecanoic acids. 相似文献
19.
Leaf waxes from spring wheat varieties Selkirk and Manitou contain hydrocarbons (6%, 10%), long chain esters (14%, 13%), free acids (5%, 8%), free alcohols (19%, 21%), β-diketone (16%, 20%), hydroxy β-diketones (8%, 10%), unidentified gum (29%, 16.5%) and minor amounts of diol diesters, glycerides and aldehydes. The major hydrocarbon is nonacosane and major esters are octacosyl esters of C14–C32 acids but C20 and C22 alcohol esters of trans 2-docosenoic and tetracosenoic acids are also present (Selkirk 20%, Manitou 10% of total esters). Previously unknown trans 2-docosen-1-ol is present as an ester (Selkirk 5%, Manitou 2.5% of total esters). Free acids are C14–C32 acids and trans 2-docosenoic and tetracosenoic acids (Selkirk 30%, Manitou 9% of free acids). Octacosanol is the principal free alcohol. Hentriacontane-14,16-dione is the β-diketone and the hydroxy β-diketones are a 1:1 mixture of 8- and 9- hydroxyhentriacontane-14,16-diones. 相似文献
20.
Water permeability and composition of soluble cuticular lipids of isolated cuticular membranes from leaves of Citrus aurantium L. were investigated for 3 successive years. The average water permeability coefficient determined using 169 cuticular membranes was 1.09·10–7 cm s–1 with a standard deviation of 0.78·10–7 cm s–1. There were no significant differences in water permeability between years. Cuticular membranes are characterized by a great variability in water permeability both within and between years. Both water permeability of individual membranes and variability between membranes are shown to be determined by soluble cuticular lipids contained within the cuticular membranes. The soluble cuticular lipids of Citrus leaves are composed of fatty acids, primary alcohols, esters, and hydrocarbons. They occur in amounts of 9.84 g cm–2, which represents approx. 3% of the total mass of isolated cuticular membranes. The specific weight of cuticular membranes (365.4 g cm–1) and total amount of soluble cuticular lipids did not vary significantly between years. Significant differences were observed for the amounts and composition of the constituent classes of lipids. Six homologues comprise 86% of the fatty acids (C16; C18; C19; C21; C24; C26), 83% of the primary alcohols (C24; C26; C28; C30; C32; C34) and 88% of the esters (C36; C38; C40; C41; C42; C44). Eleven major homologues amount only to 62% of the total hydrocarbons (C16; C17; C18; C20; C26; C27; C29; C30; C31; C32; C33). Variability in the composition of soluble cuticular lipids between years was much smaller than variability of water permeability and, therefore, no relation between composition of soluble cuticular lipids and water permeability could be found. It is suggested that this may be due to the fact that the lipid composition observed represents the averages of 20 to 30 membranes analyzed so that differences between individual membranes may have been leveled out.Abbreviations CM
cuticular membranes
- MX
polymer matrix
- Pd
permeability coefficient for diffusion of water
- SCL
soluble cuticular lipids
- MES
morpholinoethane sulphonic acid 相似文献