Chemical composition and variability of the volatile components from inflorescences of Cirsium species.

The present study aimed to investigate the chemical composition of the essential oils of inflorescences Cirsium spp. (Asteraceae) by GC/MS method. Essential oils were extracted from the inflorescences of Cirsium pannonicum (Link), Cirsium ligulare Boiss.

Application of PLE for the determination of essential oil components from Thymus vulgaris L.

Essential plants, due to their long presence in human history, their status in culinary arts, their use in medicine and perfume manufacture, belong to frequently examined stock materials in scientific and industrial laboratories. Because of a large number of freshly cut, dried or frozen plant samples requiring the determination of essential oil amount and composition, a fast, safe, simple, efficient and highly automatic sample preparation method is needed. Five sample preparation methods (steam distillation, extraction in the Soxhlet apparatus, supercritical fluid extraction, solid phase microextraction and pressurized liquid extraction) used for the isolation of aroma-active components from Thymus vulgaris L.

The changes of propofol concentration in human cerebrospinal fluid after drug infusion.

Objective: Investigation of the propofol concentration changes in cerebrospinal fluid (CSF) after the termination of the drug infusion.

Methods: Nine patients (American Society of Anesthesiologists classes I-III) scheduled for elective intracranial procedures were studied. Propofol was applied in the form of target control infusion.

The level of jasmonic acid in Arabidopsis thaliana and Phaseolus coccineus plants under heavy metal stress.

The effect of heavy metal stress as a potent abiotic elicitor for triggering an accumulation of jasmonic acid (JA) was investigated. Copper and cadmium in in vivo conditions induced accumulation of jasmonates in mature leaves of Arabidopsis thaliana and in young and oldest Phaseolus coccineus plants. The dynamics of jasmonate accumulation showed a biphasic character in both plants.

Comparison of terpene composition in Engelmann spruce (Picea engelmannii) using hydrodistillation, SPME and PLE.

Terpenes emitted by conifer trees are generally determined by analysing plant extracts or essential oils, prepared from foliage and cones using steam distillation. The application of these procedures limits experiments to cut plant materials. Recently headspace techniques have been adopted to examine terpene emission by living plants.

Essential oil from fruit of Peucedanum tauricum Bieb.

Essential oil from fruit of Peucedanum tauricum Bieb, was qualitatively and quantitatively investigated. The content of oil determined by distillation with water and m-xylene was 2.2% of dry mass.

Comparative analysis of the composition of the volatile oils of two forms of Achillea crithmifolia W. et. K.--diploid and tetraploid.

The genus Achillea L. includes more than 100 species and is a polyploid complex of di-, tetra-, hexa- and octaploids, individuals.

The chemical composition of Microbiota decussata.

From the leaves of Microbiota decussata (Cupressaceae) biflavones: cupressuflavone, amentoflavone and 7-O-methylamentoflavone were isolated and identified. The amount of cupressuflavone in Microbiota decussata and xCupressocyparis leylandii (Leyland cypress) (Cupressaceae) was determined by HPLC (1.82% and 0.

Antifungal activity of the essential oils from some species of the genus Pinus.

The chemical composition of the essential oils from the needles of Pinus ponderosa (north american pine), P. resinosa (red pine) and P. strobus (eastern white pine) has been determined by GC/MS (FID).