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1.
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   

2.
The kernel oils of Quercus robur and Quercus cerris were obtained by Soxhlet extraction using petroleum ether. Oil yields were found to be 5.2–5.6% and 4.3–4.8% for Q. robur and Q. cerris kernel, respectively (expressed in g per 100 g of dried plant material). The physical and chemical constants, unsaponifiable matter and total fatty acids were determined. The total fatty acid composition of oils was determined by GC in the methyl ester form. Considering the composition and content of fatty acids, the examined kernel oils were very similar. Seven fatty acid components were identified in both oils: palmitic, stearic, arachidic, palmitoleic, oleic, linoleic, and -linolenic. In Q. robur and Q. cerris kernel oils the principal acids were oleic (44.3% and 43.0%, respectively) and linoleic (37.2% and 32.6%, respectively), followed by a significant amount of palmitic acid.Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 347–348, September–October, 2004.  相似文献   

3.
A new flavonoid, kaempferol-3,4′-di-O-α-L-rhamnopyranoside (1), and three known flavonoids (2–4) were isolated from the aerial parts of T. communis L. The structure of the new compound was elucidated on the basis of spectroscopic data. Compounds 1 and 2 showed significant antioxidant activity (IC50 187.151 ± 0.821 μM, and 92.079±0.513 μM, respectively), whereas compounds 3 and 4 showed moderate activity in DPPH free radical scavenging assays. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 295–297, May–June, 2009.  相似文献   

4.
Alkylation of Reissert compounds derived from 3-methylisoquinolines with several 2-cyanobenzylbromides followed by hydrolytic cleavage provided the corresponding 1-benzyl-3-methylisoquinolines. Treatment of the latter with methylmagnesiumiodide caused cyclization to the title compounds rather than formation of 2-acetylbenzylisoquinolines.  相似文献   

5.
A new C-glucoside, 3,4-epoxy-5-hydroxymethyl benzoate 2-C-β-glucoside (1), together with a known alkaloid, 1H-indole-3-carbaldehyde (2), were isolated from the whole plant of Commelina communis L. The structures of these compounds were determined by 1D, 2D NMR and MS techniques. Published in Khimiya Prirodnykh Soedinenii, No. 1, pp. 51–52, January–February, 2009.  相似文献   

6.
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   

7.
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   

8.
The new natural compound lavandoside with the structure ferulic acid 4-O-β-D-glucopyranoside was isolated by column chromatography over silica gel and polyamide from the extract of Lavandula spica flowers. The chemical structure of lavandoside was established using UV, NMR, and mass spectra and chemical transformations. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 133–134, March–April, 2008.  相似文献   

9.
The purpose of this study is to determine the survival and nisin production behaviors of two strains of Lactococcus lactis under different stress conditions that represent the food ecosystem. In this respect, the survival ratios of two nisin producers were determined under different pH, temperature, NaCl, and bile salt concentrations. Then, nisin production levels of the strains were determined at each stress conditions. Both strains had similar growth or inactivation patterns under the same stress conditions. NaCl and bile salt stresses on the survival ratio of the strains could be successfully described by the exponential decay function, whereas Gaussian function produced good fits for temperature and pH stresses. The nisin activity of two nisin producers (in their mid-exponential and/or early stationary phase) decreased dramatically under all stress conditions, except osmotic (NaCl) and low temperature applications. The results of this study showed that two nisin producers had similar adaptive responses under severe stress conditions, which could be described by appropriate mathematical equations. Moreover, the effect of harsh environment on the nisin activity of L. lactis strains depends on the stress factors applied.  相似文献   

10.
Group-theoretical and quantum-chemical investigations of the spectrum of low-lying excited states have been performed by the ROHF and FCI-RAS (Full CI in Restricted Active Space) methods for 3d metal endofullerenes (MEFs) M@C60 (M =Mn, Cr, and Fe) in different charged states. The major purpose of this study is quantum-chemical verification of the anomalous (“non-Bethe’s”) character of splitting of the d N atomic states in an electrostatic field with icosahedral symmetry, predicted previously within the theory of integral invariants theory. The interrelation between the integral invariants theory and the quantumchemical methods applied in this work is considered in detail. Our calculations suggest that the d N atomic states in the icosahedral field generated by fullerene C60 (I h ) on a metal atom (ion) remain non-split for different charged states of the metal and C60. Reasons for this phenomenon and other possible approaches to verification of the prediction are discussed. It is demonstrated that the d N states of the encapsulated metal are split in icosahedral 3d MEFs only under very strong compression of these structures.  相似文献   

11.
A new stilbene glycoside, 5-methylresveratrol-3,4′-O-β-D-diglucopyranoside (1), was isolated from the n-butanol fraction of the rhizomes of Veratrum dahuricum, together with five known stilbenoids: resveratrol-3-O-β-D-glycoside (2), 4′-methylresveratrol-3-O-β-D-glycoside (3), oxyresveratrol-4′-O-β-D-glycoside (4), oxyresveratrol-3-O-β-D-glycoside (5), and oxyresveratrol-3,4′-O-β-D-diglycoside (6), and found for the first time in the investigated plant. The structures of six isolates were identified on the basis of 1D and 2D NMR data. Compounds 1–6 showed platelet aggregation inhibition, and compound 1 had an IC50 value of 383.6 μM against platelet aggregation induced by AA. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 279–282, May–June, 2009.  相似文献   

12.
Microorganisms producing lipase were isolated from soil and sewage samples and screened for enantioselective resolution of (R,S)-methyl mandelate to (R)-mandelic acid. A strain designated as GXU56 was obtained and identified as Burkholderia sp. Preparing immobilized GXU56 lipase by simple adsorption on octyl sepharose CL-4B, the optimum temperature was shifted from 40 °C (free lipase) to 50 °C (immobilized lipase), and the optimum pH was shifted from 8.0 (free lipase) to 7.2 (immobilized lipase). The immobilized enzyme displayed excellent stability in the pH range of 5.0–8.0, at the temperatures below 50 °C and in organic solvents compared with free enzyme. Enantioselectivity ratio for (R)-mandelic acid (E) was dramatically improved from 29.2 to more than 300 by applying immobilized lipase in the resolution of (R,S)-methyl mandelate. After five cycles of use of immobilized lipase, conversion and enantiomeric excess of (R)-mandelic acid were 34.5% and 98.5%, respectively, with enantioselectivity ratio for (R)-mandelic acid (E) of 230. Thus, octyl-sepharose-immobilized GXU56 lipase can be used as a bio-resolution reagent for producing (R)-mandelic acid.  相似文献   

13.
The structure of glucofructans from Taraxacum officinale roots growing in Buryatia was studied by chemical, chromatographic, and spectral methods. It was found that fructose,glucose, saccharose, 1-kestose, and nystose were present in the free state. The structures of the two dominant polymeric compounds, TGf-1 (5.7 kDa) and TGf-2 (2.6 kDa), which were linear inulin-type macromolecules consisting of fructofuranose units bonded through β-(2→1)-bonds, were studied. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 125–127, March–April, 2009.  相似文献   

14.
A new compound of formula C28H48O with mp 179-180°C (aqueous ethanol) that was called eucanbin was isolated pure by column chromatography of the ethanol extract of the aerial part of Eupatorium cannabinum L. The structure 24α-methylcholest-20(21)-en-3β-ol was assigned based on chemical and spectral data. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 318–320, May–June, 2009.  相似文献   

15.
The crystal and molecular structure of tris(m-chlorophenyl)phosphine selenide, C18H12Cl3PSe (I), was investigated by X-ray diffraction (XRD) analysis. The trigonal rhombohedral structure of I (space group \(R\overline 3 c\), a = 14.110(2) Å, c = 32.360(4) Å, Z = 12) was solved by direct methods and refined by least squares in an anisotropic approximation (R = 0.029) for 1319 averaged measured reflections (CAD-4 automatic diffractometer, λCuKα).  相似文献   

16.
A (n, n + 1)-graph G is a connected simple graph with n vertices and n + 1 edges. In this paper, we determine the lower bound for the Hosoya index in (n, n + 1)-graphs in terms of the order n, and characterize the (n, n + 1)-graph with the smallest Hosoya index.  相似文献   

17.
Research results on the isolation and identification of ecdysteroids from plants of the Silene L. genus were presented.Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 472–475, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

18.
New N-acylates of the norditerpenoid alkaloid N-deacetyllappaconitine that were modified in the aromatic ring and are interesting as potential pharmacologically valuable compounds were prepared. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 275–279, May–June, 2008.  相似文献   

19.
The rare α,4,2′,4′-tetrahydroxydihydrochalcone, flavanones liquiritigenin and naringenin, isoflavones calycosin and 5-methoxydaidzein, and reduced stilbene dihydroresveratrol were isolated for the first time from Maackia amurensis wood. The structures of the pure compounds were established using 2D NMR COSY, NOE, HMBC, and HSQC experiments. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 575–577, November–December, 2008.  相似文献   

20.
A polysaccharide with MW 25,000 consisting of arabinose, galactose, and mannose units in a 1:2.8:3.2 ratio was isolated from Gleditsia macracantha seeds. Chemical and spectral methods established that the polysaccharide was a branched galactomannan with side branches consisting of arabinose units. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 128-130, March-April, 2009.  相似文献   

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