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1.
The fatty-acid composition of two Limonium plant species (Plumbaginaceae), including both saturated and polyunsaturated acids, was determined for the first time using chromatography—mass-spectrometry. High contents of palmitic, oleic, linolenic, and linoleic acids were found. Methyl esters of fatty acids in Limonium Popovii were identified by mass spectrometry as hexadecanedioic, eicosanedioic, and docosanedioic acids.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 344–346, September–October, 2004.  相似文献   

2.
The seed oils of Cistus laurifolius, C. salviifolius, and C. creticus were investigated for their fatty acids by employing capillary GC and capillary GC-MS. The results of this study indicated that palmitic, linoleic, linolenic, oleic, stearic, and behenic acids were found in all of these three seed oils of Turkish origin. In addition, an important polyunsaturated fatty acid, linoleic acid, was the major fatty acid in all of these oil samples.Published in Khimiya Prirodnikh Soedinenii in No. 6, pp. 433–434, November–December.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

3.
Phase transitions of poly(N-isopropylacrylamide-co-acrylic acid) (PiPA-AA) and poly(N,N- diethylacrylamide-co-acrylic acid) (PdEA-AA) in water have been investigated by means of turbidimetry, Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). The phase transition temperatures (Tp) of these copolymers increase with the degree of ionization () of the acrylic acid (AA) units, which in turn is dependent on the pH of the solutions. Apparent values of pKa for the AA units, determined from the pH dependencies of Tp, are 4.7 and 5.4 for PiPA-AA and PdEA-AA, respectively. Differences between Tp for PiPA-AA and Tp for PiPA homopolymer (Tp) are +1.5 and –0.2 °C/mol% of AA at =1 and 0, respectively. The values of Tp for PdEA-AA are +2.6 (ionic) and –0.5 (nonionic)°C/mol%, indicating that the incorporated AA units have a larger effect on PdEA than on PiPA. DSC measurements performed with each of these copolymers at different pH values show a linear relationship between Tp and the enthalpy of transition (H). IR measurements of PiPA-AA show that the profiles of IR bands from both iPA and AA units exhibit critical changes at Tp of the copolymer. Heating the solution above Tp leads to shifts of the amide II, C–H stretch, and C–H bend bands from the iPA units toward lower wavenumbers, as well as a shift of the amide I band from the iPA units toward higher wavenumbers. A decrease in the intensity of the symmetric C=O stretch IR band from carboxylate anions (1560 cm–1), and an increase in the intensity of the C=O stretch band from COOH groups (1705 cm–1) suggest that a partial protonation of the carboxylate groups (COO+H+COOH) takes place upon the phase transition.  相似文献   

4.
Acid-base and complexation properties of gem-disubstituted phosphorus acids, viz., methylenediphosphonic, 1-hydroxyethylidene-1,1-diphosphonic, P,P-diphenylmethylene-diphosphinic, and P, P-diphenyl-1-hydroxyethylidene-1, 1-diphosphinic acids, were studied in aqueous solutions and in the presence of biomimetics (micelles of ionic surfactants). The dissociation constants of the acids and stability constants of complexes with magnesium(II) and copper(II) ions were determined in aqueous solutions and microheterogeneous media containing sodium dodecyl sulfate, cetylpyridinium chloride, or cetylpyridinium nitrate (ionic strength 0.1 mol L–1, temperature 25°C).Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1919–1925, September, 2004.  相似文献   

5.
The structure of a new dimeric indole alkaloid, arundarine, isolated from the roots of the plant Arundo donax L. (Poaceae) was determined. On the basis of spectroscopic data, arundarine was identified as 5-[3-(2-dimethylaminoethyl)indol-1-yl]-6-hydroxy-N 2-methyl-1,2,3,4-tetrahydro--carboline.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1697–1699, August, 2004.For Part 14, see Ref. 1.  相似文献   

6.
Fatty acid profile data for refined cold-pressed Trichosanthes kirilowii Maxim. seed oil, in comparison to other commercially available oils — olive, rapeseed and camellia, are presented. Trichosanthes kirilowii Maxim. seed oil has high oleic and linoleic acid content and high polyunsaturated acid content. Squalene elutes as a distinct peak in the GC chromatograph. For a positive identification, MS detection was used. In the samples analyzed, squalene occurred in the range of 57.4–68.2 mg g−1.  相似文献   

7.
The composition of lipids from the aerial parts of two species of halophytes from the family Chenopodiaceae, Halostachys caspica C. A. Mey. and Halocharis hispida Bge. was determined. Neutral lipids (NL, 62.1 and 54.2%, respectively) dominated the total lipids (TL) of these plants. More than a third of the NL were esters of aliphatic alcohols and phytosterols (FAE). Fatty acids 16:0, 18:1, and 18:2 dominated the acids of FAE; 16:0, 18:1, and 18:3, the phospholipids. The principal fatty acids of glycolipids were unsaturated acids (68.3 and 75.1%) with linolenic acid dominating (44.9 and 43.5%). Presented at the 7th International Symposium on the Chemistry of Natural Compounds, Tashkent, October 16–18, 2007. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 276–278, May–June, 2009.  相似文献   

8.
The chemical composition of the fruits of the north algerian ecotype Pistacia atlantica subsp. atlantica was determined and compared to other fruits of different species in the genus growing in south Algeria and other Mediterranean regions. These fruits were analyzed for their dry matter, protein, crude oil, ash, fatty acids, and phytosterol content. The main fatty acids identified by gas chromatography were oleic (54.15%), linoleic (28.84%), and palmitic (12.21%) acids. The fruits of the north ecotype were found to be rich in protein, oil, fiber, and unsaturated fatty acids, suggesting that they may be valuable for food uses. The sterols isolated were campesterol, stigmasterol, β-sitosterol, and Δ5-avenasterol with β-sitosterol as the major constituent (85%±0.85). The biochemical data indicated an elevated MUFA rate (∼56%) in pistacia oil which may be important against certain pathologies for its nutritional and preventive virtues. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 103–105, March–April, 2007.  相似文献   

9.
A new hydroquinone diglucoside along with five known compounds was isolated from the whole plant of Lysimachia fordiana Oliv. The structure of the new compound was determined to be 2-heptyl-6-methoxy-1,4-hydroquinone-1,4-di-O--D-glucopyranoside (6). The five known compounds were identified as pentacosane (1), stigmasterol (2), 2-heptyl-6-methoxy-1,4-benzoquinone (3), palmitic acid (4), and rutin (5), respectively. This is the first report of the isolation of Lysimachia fordiana Oliv. in the family Primulaceae.Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 377–379, September–October, 2004.  相似文献   

10.
The fatty acids, sterols, and polyphenols from the fixed oils of Nigella sativa seeds originating from four locations were determined. The seeds contained respectively 30.63–34.27% and 25.66–32.77% of fixed oils using hexane and isopropyl alcohol in solvent extraction. Linoleic, oleic, and palmitic acids formed the main proportion using the two solvents, respectively: hexane 54.47–61.28%, isopropanol 56.98–67.30%; hexane 19.62–22.94%, isopropanol 18.85–21.96%, and hexane 11.17–13.60%, isopropanol 9.20–14.18%. Other minor unsaturated fatty acids were identified. Eight phytosterols were isolated and identified in the fixed oils by GC and GC/MS analysis, wherein β-sitosterol was the dominating compound that inhibits the absorption of dietary cholesterol, followed by stigmasterol, campesterol, and Δ5-avenasterol.  相似文献   

11.
Summary. L-Carnitine, L-(−)-β-hydroxy-γ-trimethylaminobutyrate, plays an important role as a factor necessary for the transport of long-chain fatty acids into the mitochondria. In order to investigate the influence of L-carnitine on hyperlipidaemias, the experimental model of the sucrose-induced hypertriglyceridaemia of the rat was used. In these experiments L-carnitine in the dose of 11 mg per day and 100 g body weight (over the period of 1 week) was able to antagonize the sucrose-induced hypertriglyceridaemia and the increase of serum free fatty acid level in female rats of the Wistar strain. Carnitine administration did not change the activities of lipogenic enzymes and fatty acid synthesis in the liver. However, L-carnitine increases the rate of hepatic fatty acid oxidation. Our results indicate a hypotriglyceridemic and free fatty acid lowering effect of L-carnitine, and suggest the use of this compound in the therapy of hyperlipidaemias.  相似文献   

12.
d-Lactic and l-lactic acids were simultaneously determined by means of a column-switching high-performance liquid chromatography (HPLC) with fluorescence detection. As a fluorescence reagent, 4-nitro-7-piperazino-2,1,3-benzoxadiazole (NBD-PZ) was employed for the fluorescence derivatization of lactic acid. The proposed HPLC system adopted both octylsilica (Cadenza CD-C8) and amylose-based chiral columns (CHIRALPAK AD-RH), which proved to give a sufficient enantiomeric separation of the lactic acid derivatives with a separation factor () of 1.32 and a resolution (Rs) of 1.98. Moreover, the features of the first elution of d-lactic acid peak in the proposed HPLC were convenient for the determination of trace amount of serum d-lactic acid, which is known to increase under diabetes. Intra-day and inter-day accuracies were in the range of 90.5–101.2 and 89.0–100.7%, and the intra-day and inter-day precisions were 0.3–1.2 and 0.4–4.8%, respectively. The proposed method was applied to determine d-lactic and l-lactic acids in human serum of normal subjects and diabetic patients, showing that both d-lactic and l-lactic acid concentrations were significantly increased in the serum of diabetic patients (n=31) as compared with normal subjects (n=21). This fact was found for the first time owing to the development of the proposed HPLC method which is able to determine d-lactic and l-lactic acid simultaneously. Finally, serum d-lactic acid concentrations determined by the proposed HPLC method were compared with those from a reported enzymatic assay, and the smaller p value between normal subjects and diabetic patients was shown by the proposed HPLC method.  相似文献   

13.
The lipid fraction of Opuntia ficus indica seeds was extracted and analyzed for its chemical and physical properties such as acid value, free fatty acid percentage (% FFA), iodine index, peroxide value, and saponification value as well as refractive index and density. The yield of seed oil was calculated as 11.75%. The acid and free fatty acid values indicated that the oil has a fairly low acidity. The triacylglycerols, fatty acids, sterols, and tocopherols were identified and their concentrations determined. The main TAGs were LLL (25.60%), OLL (21.53%), PLL (15.53%), and POL + SLL (12.73%). Linoleic acid (60.69%) was the dominant fatty acid, followed by oleic (21.42%) and palmitic (12.76%) acids, respectively. A high level of sterols making up 16.06 g/kg seed oil was present. The sterol marker, β-sitosterol, accounted for 71.60% of the total sterol content in the seed oil. Among the tocopherols present in the oil, γ-tocopherol (421.08 mg/kg) was the main constituent.  相似文献   

14.
Starch materials of different amylose content were allowed to react with saturated and unsaturated fatty acids of varying chain length from C14 to C18 under homogeneous conditions applying the solvent N,N-dimethyl acetamide in combination with LiCl. As reagent the corresponding acid chlorides and, alternatively, carboxylic acids in situ activated with toluene-4-sulfonyl chloride and N,N′-carbonyldiimidazole (CDI) were studied. Using fatty acid chlorides (FACl) and toluene-4-sulfonyl chloride-activated acids an almost complete substitution of the starch occurs. By in situ activation of the fatty acids with CDI, products with a degree of substitution up to 2 were obtained, which, in particular, represents a simple and very mild procedure.  相似文献   

15.
Integristerone A and 2-deoxy-20-hydroxyecdysone were observed for the first time in the aerial and subterrean organs of the eastern Asian plant Serratula komarovii Iljin. -Ecdysone was not found in the plants. The dynamics of phytoecdysteroid content (integristerone A, 20-hydroxyecdysone, and 2-deoxy-20- hydroxyecdysone) in the vegetative and generative organs of this species were investigated.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 404–406, September–October, 2004.  相似文献   

16.
We have developed new DNA extraction and purification procedures for investigation of mycorrhized seedlings and canned truffles. Use of these procedures on approximately 100 mg initial material enabled good sample representation. For mycorrhized seedlings, Taq polymerase inhibitors were discarded irrespective of tree species. In routine analysis we systematically used consensus primers ITS1/ITS4 to check the absence of Taq polymerase inhibitors and the presence of fungus DNA. Positive response with ITS validates other positive or negative PCR results. Absence of amplification with ITS prevents validation of other results. For canned truffles, DNA harvested from ascocarps sterilized for one and a half hours at 115°C was amplified with specific primers. We have developed consensus primers, named R12/F12, to check for the presence of amplifiable fungus DNA and the absence of Taq polymerase inhibitors. Here also, positive response with consensus R12/F12 validates other positive or negative PCR results. We have developed one primer pair specific for T. brumale and another specific for T. melanosporum. We can then characterize these two taxa, which enables the use of truffle or truffled French designations. We can also characterize T. indicum, the Asiatic black truffle that might fraudulently be sold as T. melanosporum and T. brumale. These three specific primer pairs were used independently of DNA extraction from tree seedlings or canned truffles. Our process is specific, sensitive, convenient, and quick.J.P. Douet and D. Mabru have contributed equally to this work  相似文献   

17.
Electrochemical measurements including cyclic voltammetry, differential capacity, and chronocoulometry have been used to characterize the adsorption behaviors of the zwitterionic surfactant N-dodecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate (DDAPS) on the Au(111) electrode surface. The thermodynamics of the ideally polarized electrode have been employed to determine the Gibbs excess and the Gibbs energy of adsorption. The results show that the adsorption of DDAPS has a multistate character. The first two states are observed at potentials close to zero charge. At low bulk DDAPS concentrations, it corresponds to the formation of a film of nearly flat adsorbed molecules. At higher concentrations it is converted into a hemimicellar state. The second state is formed at negative potentials and charge densities close to 0 C cm–2. It corresponds to a film of tilted molecules oriented with the hydrocarbon tail towards the metal and the polar head toward the solution.Dedicated to Professor Zbigniew Galus on the occasion of his 70th birthday and in recognition of his many contributions to electrochemistry.  相似文献   

18.
Detecting and enumerating fecal coliforms, especially Escherichia coli, as indicators of fecal contamination, are essential for the quality control of supplied and recreational waters. We have developed a sensitive, inexpensive, and small-volume amperometric detection method for E. coli -galactosidase by bead-based immunoassay. The technique uses biotin-labeled capture antibodies (Ab) immobilized on paramagnetic microbeads that have been functionalized with streptavidin (bead–Ab). The bead–Ab conjugate captures E. coli from solution. The captured E. coli is incubated in Luria Bertani (LB) broth medium with the added inducer isopropyl -D-thiogalactopyranoside (IPTG). The induced -galactosidase converts p-aminophenyl -D-galactopyranoside (PAPG) into p-aminophenol (PAP), which is measured by amperometry using a gold rotating disc electrode. A good linear correlation (R2=0.989) was obtained between log cfu mL–1 E. coli and the time necessary to product a specific concentration of PAP. Amperometric detection enabled determination of 2×106 cfu mL–1 E. coli within a 30 min incubation period, and the total analysis time was less than 1 h. It was also possible to determine as few as 20 cfu mL–1 E. coli under optimized conditions within 6–7 h. This process may be easily adapted as an automated portable bioanalytical device for the rapid detection of live E. coli.  相似文献   

19.
Consumption of trans fat has been associated with increased risk of coronary heart disease. For nutrition labeling purposes, the US Food and Drug Administration (FDA) defines trans fat as the sum of all the fatty acids with at least one nonconjugated double bond in the trans configuration. The FDA regulation states that label declarations of trans fat are not required for products that contain less than 0.5 g of trans fat per serving if no claims are made about fat, fatty acids or cholesterol. While attenuated total reflection Fourier-transformed infrared spectroscopy (ATR-FT-IR) provides reproducible measurements for samples containing more than 5% trans fat, methods based on gas chromatography (GC) are needed to measure lower trans fat levels. Trans fat quantitation by GC has recently been updated by considering more fatty acids, focusing more attention on fatty acids present in low amounts, and by using 100-m high-polarity capillary columns for optimal separation. The consistently high interlaboratory relative standard deviations (RSD, e.g., 21% at 1% trans fatty acids (TFA), 60% at 0.17% TFA), and intralaboratory RSD values (e.g., 10% at 1% TFA, 16% at 0.17% TFA) for trans fat at 1% or less of total fat reported in the collaborative study data for American Oil Chemists Society Official Method Ce 1h-05 suggest the need to carefully define the parameters associated with GC analysis of fatty acids.  相似文献   

20.
Several (E)- and (Z)-3-styrylchromones were prepared by two different methodologies, the Wittig reaction of chromone-3-carboxaldehyde with benzylic ylides and the Knoevenagel condensation of chromone-3-carboxaldehyde with phenylacetic acids in the presence of potassium tert-butoxide under microwave irradiation. The Knoevenagel reaction followed by a decarboxylation offered an efficient and diastereoselective method for preparing (E)-3-styrylchromones in a shorter reaction time. It was also demonstrated that phenylacetic acid can also be substituted with success by phenylmalonic acid. The stereochemistry of all products was assigned by NMR experiments. Correspondence: Artur M. S. Silva, Chemistry Department, University of Aveiro, 3810-193 Aveiro, Portugal.  相似文献   

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