Gas-chromatographic determination of the composition of the volatile components of the oleoresins of some species of conifers

Using the method of analytical GLC in a glass capillary column, the compositions have been studied of the volatile fractions of the oleoresins of five species of conifers:Larix decidua,Pinus strobus,Pinus mugo,Picea excelsa, andPinus abies. In the oleoresins 21 monoterpene and 22 sesquiterpene compounds were identified from their relative retention times and with the aid of additives. The main components of the volatile fractions of the oleoresins were α- and β-pinenes and 3-carene among the monoterpenes, and longifolene caryophyllene, δ- and γ-cadinenes and α-murolene among the sesquiterpene compounds. The quantitative analysis of the fractions was carried out by the method of internal normalization from averaged correlation coefficients.     

Neutral diterpenoids of oleoresins of five species of conifers of Transcarpathia

The compositions of the neutral diterpenoids of the oleoresins of five species of conifers growing in the Transcarpathia have been studied. It has been found that the oleoresins ofAbies alba M.,Larix decidua M., andPicea excelsa L. contain more than 50% of neutral diterpenoids. The group and qualitative compositions of the oxygen-containing diterpenoids have been determined. In the oleoresins ofAbies alba,Picea excelsa, andPicea abies tertiary alcohols — cis-abienol and isocembrol — predominate, while inLarix decidua the main component is the hydroxy ester larixyl acetate. Primary alcohols related to the resin acids have been found in all the oleoresins investigated. Features of the distribution of diterpenoids according to the species of conifers have been revealed. The results obtained are necessary for the chemotaxonomy of conifers of the family Pinceae.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodynkh Soedinenii, No. 6, pp. 812–816, November–December, 1988.     

Lipopolysaccharides of marine blue-green algae

The lipopolysaccharides (LPSs) have been isolated from two blue-green algae,Oscillatoria hilderbrandtii andNostoc sp. by the method of phenol-water extraction. The LPSs contain polysaccharide and lipid components. The polysaccharide fraction fromO. hildebrandtii consists predominantly of 1,3-bound rhamnose residues with a substituent in the second position. The rhamnose residues in the polysaccharide fraction ofNostoc are connected by 1,3- and 1,2-glycosidic bonds. The lipid components of the LPSs fromO. hilderbrandtii andNostoc consist of palmitic and steric acids, with glucosamine and glucose.     

Alkaloids of Rauwolfia species growing in Vietnam

Reserpine, ajmaline, serpentine, ajmalicine, isoreserpiline, and other alkaloids have been isolated from the roots ofRauwolfia cambodiana Pierre ex Pitard,R. verticillata Baill. andR. serpentina Benth.R. vomitoria Afz. was the richest in alkaloids.     

Pentaketide metabolites of mutants and the biosynthesis of melanin inVerticillium tricorpus

From mutants of the fungusVerticillium tricorpus Isaac., having various genetic blocks in the biosynthesis of melanin, we have isolated and identified scytalone, flaviolin, 3,3′-biflavinolin, 2-hydroxyjuglone, vermelone, and 1,8-dihydroxynaphthalene, which, in combination with the results of complementation analysis, has enabled the main stages of the biosynthesis of melanin inV. tricorpus to be established. The results on the inhibition of the biosynthesis of melanin by tricyclazole in natural isolates ofV. tricorpus indicates that the initital stages of the biosynthesis of melanin inV. tricorpus up to the formation of 1,3,8-trihydroxynaphthalene are identical with those ofVerticillium dahliae.     

Size-dependent core-level spectroscopy of free neutral clusters

Studies of the electronic and geometric structure of free clusters are presented to highlight the application of core-level spectroscopy using synchrotron radiation to cluster physics. The study of electronic structure deals with the excitation of the C 1s electron to the Rydberg states of the molecule in CH₄ clusters and demonstrates the gradual evolution of the surface and bulk-specific spectral features with cluster size. A second study investigates the K-edge excitations in Ne clusters and is concerned with extracting structural information from the X-rays Absorption Near-Edge Structure (XANES).     

Glycosides of marine invertebrates. VIII. Steroid glycosides of the holothurianIsostichopus badionotus

The steroid glycoside fraction ofIsostichopus badionotus, consisting of a mixture of D-xylosides of steroid alcohols, has been isolated by column chromatography on silica gel. The mixture of aglycones obtained after acid hydrolysis was separated with the aid of argentation chromatography into several fractions. GLC-MS analysis, and also the use of IR and¹³C NMR spectroscopy has shown that the steroid glycosides ofI. badionotus are xylosides of Δ⁰-, Δ⁷-, Δ²²-, and Δ^7.22-, C₂₇-, C₂₈-, and C₂₉-steroids of the cholestane series.     

Lipids of the fruit ofAcanthopanax sessiliflorus

In the lipids of the seeds and pericarp of the introduced speciesAcanthopanax sessiliflorus (Rupr. et Maxim.) Seem (familyAraliaceae), 23 classes of compounds have been detected, of which 19 have been identified. Sixteen of the classes have been studied. The lipids of the pericarp contain a more complex set of components than the seeds. Hydroxyacyldiacylglycerides, fatty acid methyl esters, and a complex group of pthalicacidesters have been detected in the familyAraliaceae for the first time. The fatty acid compositions of the seed and pericarp lipids are characterized by a high level of petroselinic acid.     

Pheromones of insects and their analogs

From cyclohexene and caproaldehyde, using ozonolysis and the Knoevenagel reaction, we have synthesized hexadeca-7Z,11E-dien-l-yl acetate — the sex pheromone ofSitotroga cerealella and a component of the sex pheromone ofPectinophora gossypiella.     

Lipids of the biomass ofRuta graveolens,grownin vivo andin vitro

A lower content of chlorophylls, phospholipids, and linolenic acid and a higher content of rutin, carotenoids, and xanthophylls in the biomass ofRuta graveolens L. obtainedin vitro has been found as compared with these indices from the epigeal part of the plant grownin vivo.     

Isoform specific gene auto-regulation via miRNAs: a case study on miR-128b and ARPP-21

In this study, we investigate whether miRNAs located within “host” protein-coding genes may regulate the expression of their host genes. We find that 43 of 174 miRNAs encoded within RefSeq genes are predicted to target their host genes. Statistical analysis of this phenomenon suggests that gene auto-regulation via miRNAs may be under positive selective pressure. Our analysis also indicates that several of the 43 miRNAs have a much lower expectation of targeting their host genes by chance than others. Among these examples, we identify miR-128b:ARPP-21 (cyclic AMP-regulated phosphoprotein, 21 kD) as a case in which both the miRNA and the target site are also evolutionarily conserved. We provide experimental support for this miRNA:target interaction via reporter silencing assays, and present evidence that this isoform-specific gene auto-regulation has been preserved in vertebrate species in order to prevent detrimental consequences of ARPP-21 over-expression in brain.     

Gas-chromatographic determination of the composition of the volatile components of the oleoresins of some species of conifers

Using the method of analytical GLC in a glass capillary column, the compositions have been studied of the volatile fractions of the oleoresins of five species of conifers:Larix decidua,Pinus strobus,Pinus mugo,Picea excelsa, andPinus abies. In the oleoresins 21 monoterpene and 22 sesquiterpene compounds were identified from their relative retention times and with the aid of additives. The main components of the volatile fractions of the oleoresins were - and -pinenes and 3-carene among the monoterpenes, and longifolene caryophyllene, - and -cadinenes and -murolene among the sesquiterpene compounds. The quantitative analysis of the fractions was carried out by the method of internal normalization from averaged correlation coefficients.Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR, Novosibirsk. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 629–632, September–October, 1990.     

The mannan formed by the yeastBullera tsugae

The structure of an extracellular mannan formed by the yeastBullera tsugae has been studied. It has been shown that the repeating unit of this polysaccharide contains β-(1→3)- and β-(1→4)-bound D-mannopyranose residues in equimolar ratio. A comparison has been made of the polymer under investigation with the extracellular mannan from a yeast of the genusRhodotorula.     

Histones of the cotton plant. Molecular characteristics of histone H1

A characterization of the histones of two varieties of the cotton plant,Gossypium hirsutum andG. barbadense, has been given with the aid of various electrophoretic systems. Their molecular weights have been determined. An analysis has been made of the cleavage of histone H1 at tyrosine residues. The positive charge and the molecular length of histone H1 have been determined by the method of incomplete succinylation.     

The composition of the essential oils ofThymus marschallianus

The essential oil ofThymus marschallianus was obtained by steam distillation of freshly-gathered flowering plants growing at various heights of the Trans-Ili Ala-Tau range (Kazakhstan). The number of components detected was 49, of which 35 were identified. No appreciable differences in the composition of the essential oil with a change in the height of growth of the plant were observed. The essential oil ofTh. marschallianus and of a number of species growing in various countries have been compared.     

Structures of cucumariosides C1 and C2 — Two new triterpene glycosides from the holothurian Eupentacta fraudatrix

Two new triterpene glycosides — cucmariosides C₁ and C₂ — have been isolated from the Far Eastern holothurianEupentacta (=Cucumaria)fraudatrix Djakonov et Baranova. Their structures have been established with the aid of¹³C NMR and PMR spectroscopy, partial acid hydrolysis, periodate oxidation, and methylation as 16β-acetoxy-3-{[3-O-methyl-β-D-xylopyranosyl-(1→3)-β-D-glucopyranosyl-(1→4)] [β-D-xylopyranosyl-(1→2)]-β-D-quinovopyranosyl-(1→2)-β-D-xylopyranosyloxy}holosta-7,23,24(cis)-triene and 16β-acetoxy-3-{[3-O-methyl-β-D-xylopyranosyl-(1→3)-β-D-glucopyranosyl-(1→4)] [β-D-xylopyranosyl-(1→2)]-β-D-quinovopyranosyl-(1→2)-β-D-xylopyranosyloxy}holosta-7,22,24(trans)-triene, respectively.     

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.     

Phytoecdysteroids of plants of the genus Silene. XV. 2-Deoxy-α-ecdysone 22-O-benzoate from Silene wallichiana

A new phytoecdysteroid, 2-deoxy-α-ecdysone 22-O-benzoate, has been isolated from the epigeal organs ofSilene wallichiana Klotzch.     

Proanthocyanidins of Rhodiola semenovii

The structures of two compounds previously isolated fromRhodiola semenovii, rhodokhinoside (I) and rhodikhim (II), have been established.     

Rapid simultaneous determination of 15 nucleosides and nucleobases in marine medicinal organism Anthopleura lanthogrammica Berkly by micellar electrokinetic capillary chromatography

In this study, a rapid and reliable micellar electrokinetic capillary chromatography (MECC) method has been developed and validated for the separation and quantification of 15 nucleosides and nucleobases in a kind of marine medicinal animal Anthopleura lanthogrammica Berkly. Factors such as micelle concentration, pH, concentration of buffer, etc. were investigated in order to obtain the optimum conditions for the separation. The optimized separation procedure employed 25 mM disodium hydrogen phosphate buffer containing 70 mM sodium dodecyl sulfate (SDS) at pH 8.7 as background electrolyte, 25°C of capillary temperature and 20 kV of separation voltage. UV detection was at 260 nm and injection was hydrodynamic at 50 mbar for 3 s. The whole analysis was completed within 13 min. The relative standard deviations (RSDs) of the peak areas for method precision ranged from 1.4 to 7.6%, and the recovery was between 80.2 and 112.9%. The limit of detection (LOD) for 15 nucleosides and nuleobases was between 0.25 and 0.75 μg/mL. According to the evaluation study, the method was shown to be precise, accurate and reproducible. The proposed MECC method was successfully applied for determination of nucleosides and nucleobases in Chinese Anthopleura lanthogrammica Berkly. The result showed that the species and content of nucleosides and nucleobases in Anthopleura lanthogrammica Berkly samples were abundant.