Lipids of the seeds ofSecurinega suffruticosa

The lipid composition of the seeds ofSecurinega suffruticosa (Euphorbiaceae) has been studied, and eight classes of lipids have been identified with a predominance of triacylglycerols; the fatty acid compositions and structures of the triacylglycerols have been determined. Among the hydroxy acids of the hydroxyacylglycerols 13 components belonging to saturated, monoenic, and dienic acids of the C₁₇, C₁₈, and C₂₀ series have been identified; 12-hydroxyheptadecanoic and 12-hydroxyeicosanoic acids are new.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 277–281, May–June, 1986.     

Oxygenated acids of the reserve lipids of Rumex paulsenianus

The composition of the fatty mono- and dihydroxy acids of the fruit ofRumex paulsenianus Rech. fil. (familyPolygonaceae) has been determined by a combination of IRS, UVS, GLC, and mass-spectrometric methods. (22) Monohydroxy acids of the C₁₄–C₂₀ series, including isomers and isologues, and four dihydroxy acids from C₁₈ to C₂₀, including a new isomeric 9-OH-10, 12–17:2 acid have been detected.Institute of the Chemistry of Plant Substances, Uzbek Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 762–765, November–December, 1991.     

Nonglyceride complex of the seed oil ofOnopordum acanthium

Extraction of the comminuted seeds has yielded an oil from which have been isolated: C₃₃-C₂₅, C₁₈ and C₁₇ paraffinic hydrocarbons, C_18:1, C_18:2, C_18:3, C_17:1, C_17:2 and C_17:3 olefinic hydrocarbons, ethyl esters of C_32:0, C_31:0, C_30:0, C_29:0, and C_28:0 fatty acids, sterols with molecular weights of 414, 412, and 400, and the alcohols -amyrin and lupeol with their natural acetates. Extraction of the uncomminuted seeds has shown that the paraffinic hydrocarbons, ethyl esters, and alcohol acetates pass into the oil from the husks of the seeds. This is the first time that the C_31:0 and C_29:0 fatty acids have been detected as natural compounds, and it is the first time that the ethyl esters of C₃₄, C₃₃, C₃₂, C₃₁, and C₃₀ fatty acids have been isolated from seed oils of higher plants.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 612–615, September–October, 1979.     

Oxygenated acids of the lipids ofOnopordum acanthium seeds

The structures of the oxygenated fatty acids of the lipids ofOnopordum acanthium L. seeds have been studied by the methods of chemical, chromatographic, and spectral analyses. Triepoxy acids of the C₁₈ series and 24 monohydroxy acids with chain lengths of C₁₄–C₁₈ have been identified, of which the 8-OH-9Z,12Z-18:2 and the 14-OH-9Z,12Z-18:2 acids have been isolated as natural compounds for the first time.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 515–518, July–August, 1993.     

Determination of fatty acids in atmospheric samples via GC/MS

Summary Atmospheric precipitation and aerosol samples are characterized by a complex mixture of several organic compounds. A simple method for the simultaneous determination of the main compound classes by GC/MS is presented. In detail, seasonal variations of C₈–C₃₂ fatty acids in precipitation in a semirural area have been studied. Total fatty acids concentrations of 7–53 g/l were detected. Summer rain is characterized by high amounts of fatty acids >C₂₀ and lower amounts of C₁₁–C₂₀ species. Two effects may be responsible: larger emission rates of fatty acids during vegetation periods and an increased influence of vapour phase due to higher temperatures during summer. CPI values showed no general trend; lower CPI values for winter rain could not be observed. This would be expected if anthropogenic sources play an important role. Monounsaturated fatty acids (C_16:1, C_18:1) were more abundant during winter than in summer. High concentrations of polyunsaturated fatty acids (C_18:x) could be detected during summer. High relative concentrations of the potential oxidation products of the unsaturated species, nonanedioic acid and w-oxononanoic acid, are associated with relatively low concentrations of their precursors.     

The composition of the organic acids of CO2 extracts of some spice-aromatic plants

Summary 1. It is desirable to analyze the composition of the organic acids of CO₂ spice extracts after their preliminary separation into individual groups according to their physicochemical properties: steam-volatile, ester-bound obtained after the hydrolysis of esters of nonglyceride nature, and acids forming components of the triglycerides.2. Characteristic for the fraction of steam-volatile free acids and for the ester-bound acids in the CO₂ extracts obtained after the hydrolysis of esters of nonglyceride nature are the C₁–C₇ low-molecular-weight saturated acids of the alipatic series: formic, isovaleric, valeric, caproic, etc. The higher fatty acids present include acids with even and odd numbers of carbon atoms from C₈ to C₁₈ and also acids with saturated and unsaturated bonds.3. The compositions of the lower acids in the extracts of all the samples studied are qualitatively very similar. Their quantitative compositions differ fundamentally. At the same time, differences both in the qualitative and in the quantitative compositions of the glyceride acids of the samples investigated are more pronounced. This is due to the circumstance that fruit was subjected to extraction in one case and leaves and rhizomes in another.Krasnodar Scientific-Research Institute of the Food Industry. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 763–767, November–December, 1977.     

Composition of the triacylglycerols of the seeds of some representatives of the family labiatae

The fatty acid compositions of five species and the compositions of the triacylglycerols of 22 species of the family labiatae have been studied for the first time. Octadeca-12,13-dienoic acid has been detected in five species. The typical compositions of the triacylglycerols differs from those of known plant oils with a similar set of fatty acids by the absence of triacylglycerols of the S₃ type and the presence of the S₂U type (0.1–1.6%). The main types are SU₂ (5–24%) and U₃ (74–95%). In a comparison of the position-species composition of the oils studied it was found that the oils of the plants of this family are distinguished by a greater diversity of species of triacylglycerols and also by the nature of the distribution of the unsaturated acyl residues between the 1,3- and 2-positions. In the majority of oils studied, the 2- position is enriched with the 18:1 acid, while the 18:2 acid is distributed predominantly in the 1,3- positions, and the nature of the distribution of the 18:3 acid is determined by its proportion in the total.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 618–625, September–October, 1979.     

Lipids of the fruit of Feijoa sellowiana

The composition and amounts of liposoluble substances in the flesh and peel of feijoa fruit has been investigated. About 30 groups of lipid substances have been identified. The main groups of lipids in the flesh were triacylglycerols, sterols, cerebrosides, ceramide phosphate inositol oligosides, sulfoquinovosyldiacylglycerols, phosphatidic acids, phosphotidylglycerols and phosphatidylcholines. In the peel, hydrocarbons, sterols, esters of fatty acids and lower alcohols, cerebrosides, digalactosyldiacylglycerols, ceramide oligosides, phosphatidylglycerols, and include predominated. The fatty acids of the flesh were found to include 15 representatives (C_12:0–C_28:0), and those of the flesh 11 representatives tives (C_12:0–C_18:3).M. V. Lomonosov Technological Institute of the Food Industry, Odessa. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 464–467, July–August, 1991.     

Nonglyceride complex of the seed oil ofOnopordum acanthium

Extraction of the comminuted seeds has yielded an oil from which have been isolated: C₃₃-C₂₅, C₁₈ and C₁₇ paraffinic hydrocarbons, C_18:1, C_18:2, C_18:3, C_17:1, C_17:2 and C_17:3 olefinic hydrocarbons, ethyl esters of C_32:0, C_31:0, C_30:0, C_29:0, and C_28:0 fatty acids, sterols with molecular weights of 414, 412, and 400, and the alcohols α-amyrin and lupeol with their natural acetates. Extraction of the uncomminuted seeds has shown that the paraffinic hydrocarbons, ethyl esters, and alcohol acetates pass into the oil from the husks of the seeds. This is the first time that the C_31:0 and C_29:0 fatty acids have been detected as natural compounds, and it is the first time that the ethyl esters of C₃₄, C₃₃, C₃₂, C₃₁, and C₃₀ fatty acids have been isolated from seed oils of higher plants.     

Reversed phase planar chromatography of dansyl DL amino acids with bovine serum albumin in the mobile phase

Summary The chromatographic behavior of twelve dansyl DL amino acids, one D isomer and eleven L isomers on RP₁₈W/UV₂₅₄, RP₁₈W/F_254s, and Sil C₁₈–50 UV₂₅₄ plates developed with aqueous—organic solutions containing bovine serum albumin (BSA) as chiral complexing agent has been extensively investigated. Enantiomeric resolution is highly dependent on mobile phase pH and ionic strength, and on the concentration of both BSA and organic modifier. All the racemates have been resolved within a development time of 1 h 30 min. The selectivity factors () for the dansyl amino acids have been compared with those from planar chromatography for the corresponding DNP, DNPy, and Fmoc amino acids, and with those of the same dansyl derivatives on a column prepared from BSA bound to silica gel.     

Additivity of atomic static polarizabilities and dispersion coefficients

A new empirical method is proposed to evaluate the average molecular polarizabilities assuming the additivity of atomic static polarizability. Atomic static polarizability for each atom in a particular valence state is obtained. Calculated molecular polarizabilities of 94 non-halogenated compounds and of the bases in nucleic acids show the excellent agreement with experimental data.To check the further validity of this method, dispersion coefficients for CH₄, C₂H₆, C₃H₈,n–C₄H₁₀,n–C₅H₁₂,n–C₆H₁₄,n–C₇H₁₆,n–C₈H₁₈, H₂, H₂O and NH₃ are obtained from a sum of atomic terms using a London-type formula, and are compared with the accurate values of dipole oscillator strength distribution (DOSD) method. The results show the excellent agreement between theory and experiment.     

Variantes de mycosides caracterisees par des residus glycosidiques substitues par des chaines acyles–I: Spectres de masse des mycosides G′ et A′ peracetyles

Mass spectra of peracetylated mycosides G′ and A′ are characterised by rearranged oxonium ions, corresponding to deoxysugars which have lost an acyl chain by fragmentation in the mass spectrometer. The main carboydrate constituent of mycoside G′ is a deoxysugar with one acyl chain and a methyl group. Mycoside A′ contains deoxysugars with one acyl chain and 0, 1 or 2 methyl groups. Deoxysugars with no acyl chains and one (G′, A′) or two (A′) methyl groups are also present. The mass spectra indicate that the acyl chains might be of the mycolic type: Peaks which might correspond to a fragmentation on both sides of the methyl branching are present and the CH⁺˙?C? C₂₂H₄₅ fragment, found in the spectrum of paracetylated mycoside A′ is characteristic of the branched chain. The highest peaks (m/e 1072 and 1100) in the spectrum of paracetylated mycoside A′ can be due to a mycolic chain after loss of acetic acid, methanol and H (l) on loss of acetic acif and H (m). The nature and abundance of the mycocerosic acids which esterify the aglycones can be deduced from the same spectra, as well as the structure of these aglycones which has been established previously by degradation and mass spectrometry. In order of decreasing abundance, C₂₇ and C₂₄ mycocerosic acids are present in mycoside G′, and C₂₉, C₃₂, C₃₂, C₃₀ and C₂₇ mycocerosic acids are found in mycoside A′.     

Synthesis, spectroscopic, structural and theoretical characterization of hydrogensquarate and mononuclear Au(III)-complex of dipeptide phenylalanyltyrosine

The mononuclear Au(III)-complex ([Au(C₁₈H₁₈N₂O₄)Cl]) and hydrogensquarate ([C₂₂H₂₁N₂O₈]) of dipeptide phenylalanyltyrosine (H–Phe–Tyr–OH) have been synthezised, characterized spectroscopically and structurally by means of solid-state linear-polarized IR-spectroscopy, ¹H- and ¹³C-NMR, ESI-MS, HPLC-MS–MS, FAB-MS, TGS and DSC methods. The structure of the Au(III)-complex has been predicted theoretically by DFT calculations. The dipeptide coordinated in a tridentate manner via –NH₂, –COO⁻ and N⁻-groups. One Cl⁻ ion is attached to the metal centre as a terminal ligand, yielding a planar AuN₂OCl chromophor. The hydrogensquarate consists in positive charged dipeptide moiety and negative one hydrogensquarate (HSq⁻) anion stabilizing by strong intermolecular hydrogen bonds.     

Purification and monolayer study of the thylacoid lipids of moss marchantia polymorpha

The original lipid content of the thylakoid membranes of moss Marchantia polymorpha has been determined for the first time. In particular, the content of SQDG is almost 3 times higher than those for both of the other classes. The ratios for DGDG and MGDG are just a little bit lower than those for green algae, but almost 2 times less than those for plants. The distribution of unsaturated bonds has changed in C₁₈ -residues of fatty acids. The total content of C₁₈-residues in thylacoid lipids have been almost the same but the content of C_18:1, C_18:2 and C_18:3 are altered in the fractions of DGDG, PG and PE. The light stress produces only the quantitative, but no qualitative, changes of the thylakoid lipid composition. The properties of the thylakoid lipids and corresponding fatty acids in the monolayers at the liquid/gas interfaces have been studied. The changes in distribution of unsaturated bonds in C₁₈ residues of fatty acids at light stress have been confirmed by Langmuir method.     

Simultaneous determination of aliphatic hydrocarbons,PCBs and PCTs in pork liver by gas chromatography

Summary A multicomponent extraction/concentration procedure has been developed for the enrichment of PCBs, PCTs and aliphatic hydrocarbons (pristane, C₁₈, C₁₉, C₂₀, C₂₂, C₂₄, C₂₈, C₃₂ and C₃₆) in pork liver. These components of the enriched extract were then simultaneously determined by gas chromatography. Mean recoveries ranged from 81.5% for pristane to 93% for PCBs;CV% (0.9–6.7) indicated the method to be both precise and reproducible.     

13C NMR spectrum of coumarin

Summary The positions of the signals from the C₃, C₅, C₆, and C₇ carbon atoms in the¹³C NMR spectrum of coumarin have been established with the aid of information obtained from the¹³C NMR spectra of [3-D]-, [4-D]-, and 7-methoxycoumarins and by the use of an additive calculation based on the increments of the methoxy group in the¹³C NMR spectrum of anisole.M. V. Lomonosov Moscow State University Scientific-Research Institute of Pharmacology, Academy of Medical Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 458–462, July–August, 1975.     

Control Mechanism for Carbon‐Chain Length in Polyunsaturated Fatty‐Acid Synthases

Polyunsaturated fatty acids (PUFAs) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) are essential fatty acids. PUFA synthases are composed of three to four subunits and each create a specific PUFA without undesirable byproducts. However, detailed biosynthetic mechanisms for controlling final product profiles have been obscure. Here, the bacterial DHA and EPA synthases were carefully dissected by in vivo and in vitro experiments. In vitro analysis with two KS domains (KS_A and KS_C) and acyl‐acyl carrier protein (ACP) substrates showed that KS_A accepted short‐ to medium‐chain substrates while KS_C accepted medium‐ to long‐chain substrates. Unexpectedly, condensation from C₁₈ to C₂₀, the last elongation step in EPA biosynthesis, was catalyzed by KS_A domains in both EPA and DHA synthases. Conversely, condensation from C₂₀ to C₂₂, the last elongation step for DHA biosynthesis, was catalyzed by the KS_C domain in DHA synthase. KS_C domains therefore determine the chain lengths.     

Diterpenoids fromMarrubium peregrinum. I

Summary Two new diterpenoids have been isolated fromMarrubium peregrinum L.: a bicyclic diol C₂₀H₃₆O₂, peregrinol — and a hydroxyketolactone C₂₀H₂₅O₅, peregrinin. A substance C₁₉H₁₈O₆ has been obtained as a by-product.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 4, pp. 249–251, 1966     

Nonglyceride lipids of the seed coats ofArtemisia absinthium andOnopordum acanthium

The seed coats ofArtemisia absinthium andOnoporum acanthium have been shown to contain paraffinic hydrocarbons (C₃₁-C₂₅ and C₃₁-C₂₇, respectively), wax esters (C₃₂-C₂₃ and C₅₁-C₃₃), acetyltriterpenols (six types, five types), and acyltriterpenols with a predominance of palmitoyltriterpenols (esters of higher saturated unbranched C_32:0-C_12:0 fatty acids and triterpenols with a molecular weight of 426 belonging to the ursene group).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 154–157, March–April, 1981.     

Carbon-13 kinetic isotope effects in the decarbonylation of lactic acid of natural isotopic composition in phosphoric acid medium

The¹³C kinetic isotope effect fractionation in the decarbonylation of lactic acid (LA) of natural isotopic composition by concentrated phosphpric acids (PA) and by 85% H₃PO₄ has been studied in the temperature interval of 60–150°C. The values of the¹³C₍₁₎ isotope effects in the decarbonylation of lactic acid in 100% H₃PO₄, in pyrophosphoric acid and in more concentrated phosphoric acids are intermediate between the values calculated assuming that the C₍₁₎–OH bond is broken in the rate-controllin gstep of dehydration and those calculated for rupture of the carbon-carbon bond in the transition state. In the temperature interval of 90–130°C the experimental¹³C fractionation factors determined in concentrated PA approach quite closely the¹³C fractionation corresponding to C₍₂₎–C₍₁₎ bond scission. the¹³C₍₁₎ kinetic isotope effects in the decarbonylation of LA in 85% orthophosphoric acid in the temperature range of 110–150°C coincide with the¹³C isotope effects calculated assuming that the frequency corresponding to the C₍₁₎–OH vibration is lost in the transition state of decarbonylation. A change of the mechanism of decarbonylation of LA in going from concentrated PA medium to 85% H₃PO₄ has been suggested. A possible secondary¹⁸O and a primary¹⁸O kinetic isotope effect in decarbonylation of lactic acid in phosphoric acids media have been discussed, too.