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1.
The objective of the present study was to compare the effects of cis-9,trans-11 + trans-8,cis-10 conjugated linoleic acid (CLA) mixture to those of cis-9,trans-11 + trans-10,cis-12 CLA mixture and linoleic acid (LA) on lipoprotein profile, hepatic lipids, body composition and digestibility of dietary fat in hamsters (n = 17) fed diets containing 2% of experimental fat (w/w) for 28 days. The cis-9,trans-11 + trans-10,cis-12 CLA mixture showed higher LDL cholesterol concentrations than LA and the cis-9,trans-11 + trans-8,cis-10 CLA mixture. The cis-9,trans-11 + trans-8,cis-10 CLA mixture induced similar plasma LDL cholesterol and hepatic lipid concentrations, and coefficient of digestibility as LA, indicating no effect of the trans-8,cis-10 CLA isomer on these lipid parameters. On the other hand, the cis-9,trans-11 + trans-8,cis-10 CLA mixture induced higher plasma VLDL cholesterol and triglycerides than LA and the cis-9,trans-11 + trans-10,cis-12 CLA mixture. The cis-9,trans-11 + trans-8,cis-10 CLA mixture also induced the highest plasma glucose concentrations compared with the two other groups, indicating an impairment of glycemic control. No differences in body composition were noted between the three groups. The present results thus show that the cis-9,trans-11 + trans-8,cis-10 CLA mixture can deteriorate plasma VLDL cholesterol and triglycerides in hamsters, possibly due to an increased flux of glucose.  相似文献   

2.
In this study, we synthesized the new kinds of semiconducting polymeric gels having negative (n-type) and positive (p-type) counter ions as charge carriers. The polyacrylamide gel was doped with pyranine (8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt), having \textSO3 - {\text{SO}}_{3}^{ - } ions as side groups and Na+ as counter ions, so-called p-type semiconducting gel. The doping process was performed during the polymerization where the pyranine binds to the polymer strands over OH group chemically via radical addition. In a similar way, N-isopropylacrylamide (NIPA) gel was doped with methacrylamidopropyltrimethyl ammonium chloride (MAPTAC), having Cl as counter ions, so-called n-type semiconducting gel. Here MAPTAC was embedded by copolymerization within the polymer network (NIPA). These semiconducting gels can show different electrical properties by changing the concentration of the doping agents, swelling ratio etc. We have shown that the pn junction, formed by combining p-type and n-type gels together in close contact, rectifies the current similar to the conventional Si and Ge diodes.  相似文献   

3.
Lesquerella fendleri is a promising new crop whose seed contains hydroxy FATG with potential industrial uses as well as substantial amounts of valuable gums. The defatted L. fendleri seeds also contain more than 30% protein. The objective of this study is to process and characterize this protein component for possible future uses in food. Hexane-defatted seed has more than 30% protein content. Defatted lesquerella meal was extracted sequentially with 0.5 M sodium chloride (2×), water, 70% ethanol, and 0.1 N sodium hydroxide (2×). Each sodium chloride extract was dialyzed against deionized water and centrifuged to separate the water-soluble fraction (albumin) from the salt-soluble fraction (globulin) before freeze-drying. The ethanol extract and the neutralized sodium hydroxide extracts (glutelin) were dialyzed against water and freeze-dried. Albumin had the highest proportion of lysine and sulfur amino acids per 16 g nitrogen among all the fractions analyzed. Glutelin and globulin accounted for the highest amount of protein nitrogen. SDS-PAGE of the reduced albumin, globulin, and glutelin showed the presence of several protein bands with M.W. ranging from 7 to 98 kDa. Nitrogen solubility of defatted lesquerella meal from pH 2 to 12 indicated a solubility minimum of 15% around pH 4.2 and a solubility of 75% at pH 11.5. Nonprotein nitrogen of defatted meal was 12% of total nitrogen. Defatted lesquerella meal has the potential for food use based on good nitrogen solubility and good amino acid composition.  相似文献   

4.
N‐Dodecyl‐N,N‐di(2‐hydroxyethyl) amine oxide (C12DHEAO) and N‐stearyl‐N,N‐di(2‐hydroxyethyl) amine oxide (C18DHEAO) were synthesized with N‐alkyl‐diethanolamine and hydrogen peroxide. Their chemical structures were confirmed using 1H‐NMR spectra, mass spectral fragmentation and FTIR spectroscopic analysis. It was found that C12DHEAO and C18DHEAO reduced the surface tension of water to a minimum value of approximately 28.75 mN m?1 at concentration of 2.48 × 10?3 mol L?1 and 32.45 mN m?1 at concentration of 5.21 × 10?5 mol L?1, respectively. The minimum interfacial tension (IFTmin) and the dynamic interfacial tension (DIT) of oil–water system were measured. When C18DHEAO concentration was in the range of 0.1–0.5%, the IFTmin between liquid paraffin and C18DHEAO solutions all reached the ultra‐low interfacial tension. Furthermore, their foam properties were investigated by Ross‐Miles method, and the height of foam of C12DHEAO was 183 mm. It was also found that they showed strong emulsifying power.  相似文献   

5.
The sandalwood kernels of Santalum insulare (Santalaceae) collected in French Polynesia give seed oils containing significant amounts of ximenynic acid, E-11-octadecen-9-oic acid (64–86%). Fatty acid (FA) identifications were performed by gas chromatography/mass spectrometry (GC/MS) of FA methyl esters. Among the other main eight identified fatty acids, oleic acid was found at a 7–28% level. The content in stearolic acid, octadec-9-ynoic acid, was low (0.7–3.0%). An inverse relationship was demonstrated between ximenynic acid and oleic acid using 20 seed oils. Results obtained have been compared to other previously published data on species belonging to the Santalum genus, using multivariate statistical analysis. The relative FA S. insulare composition, rich in ximenynic acid is in the same order of those given for S. album or S. obtusifolium. The other compared species (S. acuminatum, S. lanceolatum, S. spicatum and S. murrayanum) are richer in oleic acid (40–59%) with some little differences in linolenic content.  相似文献   

6.
This study describes work aimed at the rapid evaluation of the fatty acid (FA) composition of Turkish Rhododendron species, particularly the leaves and the flowers of the toxic plants, R. ponticum and R. luteum. The FA profiles of the available parts of three other nonpoisonous Rhododendron species were also investigated. Subtotal extracts obtained (using n-hexane, chloroform and methanol) from total chloroform:methanol (1:1) extracts were analyzed and compared to each other. Palmitic acid was found to be the most abundant FA in almost all Rhododendron extracts, and the majority of leaf and flower extracts contained significant portions of C18 unsaturated FAs (18:1n-9, 18:2n-6, 18:3n-3). The n-hexane extracts of R. ponticum leaves and R. luteum flowers were unique, as they contained an unusual series of even-chain iso FAs (C16–C24). Especially the n-hexane extracts were found to comprise uncommon FAs with odd-numbered carbons (C13–C29). Overall, n-hexane proved to be the best solvent by representing the richest FA profile, whereas chloroform or methanol appeared less suitable for FA analyses. Appreciable intra-species variations in FA compositions among the leaves as well as other anatomical parts examined were observed. This study highlights the chemotaxonomical importance of the FAs for the genus Rhododendron.  相似文献   

7.
Jatropha curcus L. oil has emerged as one of the most important raw materials for biodiesel production. However, no detailed study has been reported on characterizing the lipid constituents of jatropha oil. The present study revealed that the total oil content of jatropha seeds was 32% with a composition of 97.6% neutral lipids, 0.95% glycolipids and 1.45% phospholipids. The fatty acid composition of total lipids, neutral lipids, phospholipids and glycolipids was also determined and found to contain oleic acid (18:1) and linoleic acids (18:2) as major fatty acids. The phospholipids fraction was further characterized and quantified and found to contain phosphatidyl choline (PC) 60.5%, phosphatidyl inositol (PI) 24% and phosphatidyl ethanolamine (PE) 15.5%. The fatty acid composition and the positional distribution of the fatty acids of individual phospholipids were also reported.  相似文献   

8.
Amino acids in nectar have received less attention than the more abundant sugars. The dilute nectars of 32 species of southern African plants that are pollinated by passerine birds were analyzed by HPLC, and the effect of pollen contamination and the variation among inflorescences and plants were also examined. Aloe marlothii and some Erythrina species were found to have high total amino acid concentrations, sometimes exceeding 100 mM. Other Aloe species, as well as Greyia, Strelitzia, Schotia, Cotyledon, and Melianthus, had low nectar amino acid concentrations. Total amino acid concentrations varied much more than the sugar concentrations of these nectars as measured with a refractometer. Pollen contamination, previously claimed to be a major source of error in the measurement of nectar amino acids, had no effect on amino acids in the nectar of A. marlothii. Variation among inflorescences of Erythrina lysistemon was greater than that among trees, and most of the variation was because of relatively abundant nonessential amino acids such as asparagine and glutamine. High amino acid concentrations, especially in ‘dilute’ nectars, represent a substantial contribution of nonsugar solutes to ‘sugar’ concentrations measured with a refractometer. Amino acids in nectar may contribute to the nitrogen requirements of bird pollinators.  相似文献   

9.
Few studies report the individual effect of 9c,11t- and 10t,12c-CLA on human energy metabolism. We compared the postprandial oxidative metabolism of 9c,11t- and 10t,12c-CLA and oleic acid (9c-18:1) in 22 healthy moderately overweight volunteers. After 24 weeks supplementation with 9c,11t-, 10t,12c-CLA or 9c-18:1 (3 g/day), subjects consumed a single oral bolus of the appropriate [1-13C]-labeled fatty acid. 8 h post-dose, cumulative oxidation was similar for 9c-18:1 and 10t,12c (P = 0.66), but significantly higher for 9c,11t (P < 0.01).  相似文献   

10.
Zhukova NV 《Lipids》2007,42(12):1169-1175
Two nudibranch mollusks, Chromodoris sp. and Phyllidia coelestis, collected from tropical waters of the Northwestern Pacific, were analyzed for lipids. The aim of this study was to fill the gap in knowledge of lipid biochemistry of mollusks. Phospholipids (PL) were the dominating lipid class followed by sterols (13%). Neutral lipids were not detected in Chromodoris sp. By contrast, P. coelestis contained TAG, diacylglyceryl ether, long chain alcohol and esters of sterols. Among PL, PC was predominant (about 50%); PE, PS and CAEP were almost in equal proportions. Sixty five FA were identified as methyl esters and N-acyl pyrrolidides by GC-MS. The sea slugs exhibited a wide diversity of FA. The common marine n-3 PUFA, 20:5n-6 and 22:6n-3, constituted 0.6-1.3% of the total FA, whereas n-6 PUFA, 22:4n-6, 20:4n-6, and 18:2n-6, were the main (25%). Among monounsaturated FA, 7-21:1 was the main (up to 6.2%). The non-methylene-interrupted (NMI) FA were found (9.4 and 12.4%), including the known 5,11-20:2, 5,13-20:2, 7,13-22:2, 7,15-22:2 and a novel isomer 7,13-21:2 (up to 3.9%). The pathway of its biosynthesis was suggested. A series of very long chain FA (VLC FA), with the main 5,9-25:2 and 5,9-26:2, were identified. High level of VLC FA (8.7 and 11.7%) in sea slugs is apparently the result of predation on sponges. Another unique feature concerned a high abundance of various odd and branched FA (16.7 and 34%), which could have originated from the dietary origin or symbiotic bacteria. This is the first report on lipid and FA composition of nudibranchs.  相似文献   

11.
Rontani JF  Koblízek M 《Lipids》2008,43(11):1065-1074
The fatty acid composition of the marine phototrophic bacterium Erythrobacter sp. strain MG3 was analysed. The involvement of an unusual enzymatic peroxidation of the allylic carbon 10 of cis-vaccenic acid in this strain was confirmed. This process, which seems to be a characteristic of some aerobic and anaerobic phototrophic bacteria, appeared to also act on the allylic carbon 10 of octadeca-5,11-dienoic acid. Enzymatic degradation of 10-hydroperoxyoctadec-11(cis)-enoic acid resulting from the peroxidation of cis-vaccenic acid mainly involves reduction to the corresponding hydroxy acid (probably catalysed by peroxygenases) and cleavage to the corresponding oxoacid, which is then biohydrogenated. Abiotic degradation of this hydroperoxide involves allylic rearrangement to 10-hydroperoxyoctadec-11(trans)-enoic and 12-hydroperoxyoctadec-10(trans)-enoic acids and cyclisation to the very unusual 7,10-epoxyoctadec-11(cis)-enoic acid. Several tests carried out at different periods of growth and under different growth conditions allowed to show that the induction of this enzymatic peroxidation process strongly depends on the physiological state of the cells and is enhanced during C-limitation and at low temperatures.  相似文献   

12.
Spiraea thunbergii Sieb. contains 1-O-cis-cinnamoyl--d-glucopyranose (CG) and 6-O-(4-hydroxy-2-methylene-butyroyl)-1-O-cis-cinnamoyl--d-glucopyranose (BCG) as major plant growth inhibiting constituents. In the present study, we determined the inhibitory activity of CG and BCG on root elongation of germinated seedlings of lettuce (Lactuca sativa), pigweed (Amaranthus retroflexus), red clover (Trifolium pratense), timothy (Phleum pratense), and bok choy (Brassica rapa var chinensis) in comparison with that of two well-known growth inhibitors, 2,4-dichlorophenoxyacetic acid (2,4-D) and (+)-2-cis-4-trans-abscisic acid (cis-ABA), as well as two related chemicals of CG and BCG, cis-cinnamic acid (cis-CA) and trans-cinnamic acid (trans-CA). The EC50 values for CG and BCG on lettuce were roughly one-half to one-quarter of the value for cis-ABA. cis-Cinnamic acid, which is a component of CG and BCG, possessed almost the same inhibitory activity of CG and BCG, suggesting that the essential chemical structure responsible for the inhibitory activity of CG and BCG is cis-CA. The cis-stereochemistry of the methylene moiety is apparently needed for high inhibitory activity, as trans-CA had an EC50 value roughly 100 times that of CG, BCG, and cis-CA. Growth inhibition by CG, BCG, and cis-CA was influenced by the nature of the soil in the growing medium: alluvial soil preserved the bioactivity, whereas volcanic ash and calcareous soils inhibited bioactivity. These findings indicate a potential role of cis-CA and its glucosides as allelochemicals for use as plant growth regulators in agricultural fields.  相似文献   

13.
Coriander (Coriandrum sativum L.) is a summer annual plant commonly used as fresh green herb, spice or for its essential oil. An integrated process combined steam distillation, dehulling, and screw pressing to recover the essential oil and edible oil from coriander fruit. The current work determined the impact of the dual oil extraction approach on coriander protein extractability, composition, and functional properties and compared the results with those of ground whole coriander. Coriander protein extracts were produced by the acid precipitation method. All the dehulled samples (steamed and non‐steamed) produced protein extracts with markedly higher protein content (84–90% dry basis, db) than did ground whole fruit (67% db). Coriander protein extracts showed similar amino acid compositions and had amino acid scores that were greater than those of their starting meals and soybean protein. Steam distillation had detrimental effects on the protein, based on major changes in SDS‐PAGE band patterns and reduced protein recovery [from 42 (control) to 26%]. However, solubilities of protein from steam‐distilled samples were enhanced from pH 7 to 10 (>90 versus 80% in non‐steam‐distilled coriander). Steam‐distillation did not negatively affect foaming, emulsification, and heat coagulability properties of the coriander proteins, as the values were equal to those of the non‐steamed samples.  相似文献   

14.
Microstructural, electrical, and optical properties of undoped and Nd3+-doped SiO x /SiN y multilayers fabricated by reactive radio frequency magnetron co-sputtering have been investigated with regard to thermal treatment. This letter demonstrates the advantages of using SiN y as the alternating sublayer instead of SiO2. A high density of silicon nanoclusters of the order 1019 nc/cm3 is achieved in the SiO x sublayers. Enhanced conductivity, emission, and absorption are attained at low thermal budget, which are promising for photovoltaic applications. Furthermore, the enhancement of Nd3+ emission in these multilayers in comparison with the SiO x /SiO2 counterparts offers promising future photonic applications.  相似文献   

15.
The fatty acid composition of the seed oil of 19 wild legume species from southern Spain was analyzed by gas chromatography. The main seed oil fatty acids ranged from C14:0 to C20:0. Among unsaturated fatty acids, the most abundant were linoleic, oleic and linolenic acids, except for Lathyrus angulatus, L. aphaca, L. clymenum, L. sphaericus and L. nigricans where C18:3 contents were higher than C18:1 contents. Palmitic acid was the most abundant saturated acid in studied species, ranging from 11.6% in Lathyrus sativus to 19.3% in Lens nigricans. All studied species showed higher amounts of total unsaturated fatty acids than saturated ones. Among studied species, the ω6/ω3 ratio was variable, ranging from 2.0% in L. nigricans to 13.8% in L. sativus, there being eight species in which the ω6/ω3 ratio was below 5. The fatty acids observed in these plants supports the use of these plants as a source of important dietary lipids.  相似文献   

16.
Derivatives of 2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropanecarboxylic acid (chrysanthemic acid) are classic natural pyrethroids discovered in pyrethrum plants and show insecticidal activity. Chrysanthemic acid, with two asymmetric carbons, has four possible stereoisomers, and most natural pyrethroids have the (1R,3R)-trans configuration. Interestingly, chrysanthemic acid–related structures are also found in insect sex pheromones; carboxylic esters of (1R,3R)-trans-(2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl)methanol (chrysanthemyl alcohol) have been reported from two mealybug species. In the present study, another ester of chrysanthemyl alcohol was discovered from the striped mealybug, Ferrisia virgata (Cockerell), as its pheromone. By means of gas chromatography–mass spectrometry, nuclear magnetic resonance spectrometry, and high-performance liquid chromatography analyses using a chiral stationary phase column and authentic standards, the pheromone was identified as (1S,3R)-(?)-cis-chrysanthemyl tiglate. The (1S,3R)-enantiomer strongly attracted adult males in a greenhouse trapping bioassay, whereas the other enantiomers showed only weak activity. The cis configuration of the chrysanthemic acid–related structure appears to be relatively scarce in nature, and this is the first example reported from arthropods.  相似文献   

17.
Evidence suggests that minor isomers of conjugated linoleic acid (CLA), such as trans8, cis10 CLA, can elicit unique biological effects of their own. In order to determine the effect of a mixture of t8, c10+c9, t11 CLA isomers on selected aspects of lipid metabolism, 3T3-L1 preadipocytes were differentiated for 8 days in the presence of 100 μM linoleic acid (LA); t8, c10+c9, t11 CLA; t10, c12+c9, t11 CLA or purified c9, t11 CLA. Whereas supplementation with c9, t11 and t10, c12+c9, t11 CLA resulted in cellular triglyceride (TG) concentrations of 3.4 ± 0.26 and 1.3 ± 0.11 μg TG/μg protein, respectively (P < 0.05), TG accumulation following treatment with CLA mixture t8, c10+c9, t11 was significantly intermediate (2.5 ± 0.22 μg TG/μg protein, P < 0.05) between the two other CLA treatments. However, these effects were not attributable to an alteration of the Δ9 desaturation index. Adiponectin content of adipocytes treated with t8, c10+c9, t11 mixture was similar to the individual isomer c9, t11 CLA, and both the t8, c10+c9, t11 and c9, t11 CLA groups were greater (P < 0.05) than in the t10, c12+c9, t11 CLA group. Overall, these results suggest that t8, c10+c9, t11 CLA mixture affects TG accumulation in 3T3-L1 cells differently from the c9, t11 and t10, c12 isomers. Furthermore, the reductions in TG accumulation occur without adversely affecting the adiponectin content of these cells.  相似文献   

18.
The seeds of cultivated Hibiscus spp. were extracted with supercritical carbon dioxide, and the resulting extracts were analyzed to identify the major TG components as the corresponding FAME. The seed oils were composed predominantly of oleic and linoleic FA (69.6–83.4%) with lesser amounts of palmitic acid (14.8–27.0%). Minor amounts of C14, C18, and C20 saturated FA were also detected. The oil content of the seeds was determined to be between 11.8 and 22.1 wt% for hybrid varieties and between 8.9 and 29.5 wt% for the native species from which the hybrid varieties were developed. The protein content of the defatted seed meal averaged 20% for the hybrid varieties. The composition of the extracted hibiscus seed oils suggests potential edible applications.  相似文献   

19.
Arabidopsis thaliana was used as an experimental model plant to investigate a tritrophic interaction between the plant, a specialist aphid herbivore, Brevicoryne brassicae, and its natural enemy, the parasitoid Diaeretiella rapae. The A. thaliana ecotype Col-5 was transformed with a functional 2-oxoglutarate dependent dioxygenase (BniGSL-ALK) that converts 3-methylsulfinylpropylglucosinolate and 4-methylsulfinylbutylglucosinolate to 2-propenylglucosinolate and 3-butenylglucosinolate, respectively. This transformation results in a change in the glucosinolate hydrolysis profile where 3-butenylisothiocyanate, 2-propenylisothiocyanate and 5-vinyloxazolidine-2-thione are produced in contrast to the wild-type plant where 4-methylsulfinylbutylisothiocyanate is the main product. Performance of B. brassicae was affected negatively by transforming Col-5 with BniGSL-ALK in terms of mean relative growth rates. In a series of behavioral bioassays, naïve D. rapae females were able to discriminate between B. brassicae infested and uninfested Col-5 plants transformed with BniGSL-ALK, with parasitoids showing a preference for B. brassicae infested plants. By contrast, naïve D. rapae females were unable to discriminate between aphid infested and uninfested Col-5 plants. Subsequent air entrainments of B. brassicae infested Col-5 plants transformed with BniGSL-ALK further confirmed the presence of 3-butenylisothiocyanate in the headspace. By contrast, no glucosinolate hydrolysis products were recorded from similarly infested Col-5 plants.  相似文献   

20.
The autoxidation processes of the cis-9,trans-11 (c9,t11) and trans-10,cis-12 (t10,c12) isomers of CLA were separately observed at ca. 0% RH and different temperatures. The t10,c12 CLA oxidized faster than the c9,t11 isomer at all tested temperatures. The first half of the oxidation process of t10,c12 CLA obeyed an autocatalytic-type rate expression, but the latter half followed first-order kinetics. On the other hand, the entire oxidation process of c9,t11 CLA could be expressed by the autocatalytic-type rate expression. The apparent activation energies and frequency factors for the autoxidation of the isomers were estimated from the rate constants obtained at various temperatures based on the Arrhenius equation. The apparent activation energies for the CLA isomers were greater than those for the nonconjugated n−6 and n−3 PUFA or their esters. However, the enthalpyentropy compensation held during the autoxidation of both the CLA and PUFA. This suggested that the autoxidation mechanisms for the CLA and PUFA were essentially the same.  相似文献   

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