caryophyllene and 1-octen-3-ol

The essential oils from aerial parts of Scutellaria laeteviolacea was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The characteristic odor components were also detected in the oil using gas chromatography-olfactometry (GC-O) analysis and aroma extraction dilution analysis (AEDA). As a result, 100 components (accounting for 99.11 %) of S. laeteviolacea, were identified. The major components of S. laeteviolacea oil were found to be 1-octen-3-ol (27.72 %), germacrene D (21.67 %),and β-caryophyllene (9.18 %). The GC-O and AEDA results showed that 1-octen-3-ol, germacrene D, germacrene B, and β-caryophyllene were the most characteristic odor components of the oil. These compounds are thought to contribute to the unique flavor of this plant.

Topics: Chromatography, Gas; Gas Chromatography-Mass Spectrometry; Octanols; Odorants; Oils, Volatile; Plant Oils; Polycyclic Sesquiterpenes; Scutellaria; Sesquiterpenes; Sesquiterpenes, Germacrane

The essential oil composition of Coleus aromaticus Benth. (family Lamiaceae) was examined by capillary GC and GC-MS. Analyses revealed the presence of 28 constituents, of which 16 were identified. Thymol (83.39%) was found to be the major compound, while 1-octen-3-ol, terpine-4-ol, eugenol, trans-caryophyllene, caryophyllene oxide and α-cadinol were present as minor constituents.

Topics: Chromatography, Gas; Coleus; Eugenol; Gas Chromatography-Mass Spectrometry; India; Octanols; Oils, Volatile; Plant Components, Aerial; Polycyclic Sesquiterpenes; Sesquiterpenes; Terpenes; Thymol

Melittis melissophyllum (Lamiaceae) is a perennial herb, typical of woody places, occurring in Italy with two subspecies, i.e., melissophyllum and albida. So far, the classification of these two taxa was only based on morphology, i.e., the presence of glandular trichomes, the dimension of the leaves, and the number of teeth on each side as the main discriminant characters. To find marker compounds to chemically discriminate the subsp. melissophyllum with respect to the subsp. albida, a solid-phase microextraction SPME analysis coupled with GC/FID (=flame ionization detector) and GC/MS was carried out. SPME proved to be a chemotaxonomically useful technique that permitted a clearly differentiation of the two subspecies at headspace level. The subsp. melissophyllum was characterized by high amount of the mushroom alcohol oct-1-en-3-ol and the phenolic coumarin, whilst the subsp. albida exhibited a high content in monoterpenes and sesquiterpenes, α-pinene, sabinene, and (E)-caryophyllene being the major compounds. Multivariate chemometric techniques, such as cluster analysis (CA) and principal-component analysis (PCA), were used to support chemical data and characterize the population according to the taxonomy. In addition, the micromorphology and distribution of glandular trichomes of both subspecies were studied by scanning electron microscopy (SEM).

Topics: Bicyclic Monoterpenes; Complex Mixtures; Coumarins; Gas Chromatography-Mass Spectrometry; Italy; Lamiaceae; Monoterpenes; Octanols; Oils, Volatile; Phylogeography; Plant Leaves; Polycyclic Sesquiterpenes; Principal Component Analysis; Sesquiterpenes; Solid Phase Microextraction

The volatile components and in vitro antimicrobial activities of Emblica (Phyllanthus emblica L.) essential oils (EOs) obtained by hydrodistillation (HD-EO) and supercritical fluid extraction (SFE-EO) were investigated. The compositions of volatile compounds in these oils were tentatively determined by gas chromatography-mass spectrometry. The antimicrobial activites of these two extracts were investigated with microbiological tests against Gram-positive and Gram-negative bacteria and three pathogenic fungi. The main components of both oils were beta-caryophyllene, beta-bourbonene, 1-octen-3-ol, thymol, and methyleugenol. Both essential oils showed a broad spectrum of antimicrobial activity against all the tested microorganisms. Gram-positive bacteria were more sensitive to the investigated oils than Gram-negative bacteria. SFE-EO exhibited a higher antifungal activity compared to HD-EO.

Topics: Anti-Bacterial Agents; Antifungal Agents; Eugenol; Fruit; Microbial Sensitivity Tests; Octanols; Oils, Volatile; Phyllanthus emblica; Plant Oils; Polycyclic Sesquiterpenes; Sesquiterpenes; Thymol

In tsetse both sexes feed exclusively on the blood of vertebrates for a few minutes every 2-3 days. Tsetse flies seek cover from high temperatures to conserve energy and plants provide shelter for tsetse in all the biotopes they occupy. Recently, tsetse have taken cover in plantations and under the invasive bush Lantana camara that has invaded large areas of the tsetse fly belt of Africa. Flies from such refugia are implicated in sleeping sickness epidemics. In a wind tunnel we show that both foliage and an extract of volatiles from foliage of L. camara attract three tsetse spp. from different habitats: Glossina fuscipes fuscipes (riverine), G. brevipalpis (sylvatic) and G. pallidipes (savannah). Gas chromatography analysis of volatiles extracted from leaves and flowers of L. camara coupled to electroantennograme recordings show that 1-octen-3-ol and beta-caryophyllene are the major chemostimuli for the antennal receptor cells of the three tsetse spp. studied. A binary mixture of these products attracted these flies in the wind tunnel. The gas chromatography linked electroantennograme analysis of the L. camara extracts also show that the antennal receptor cells of the three tsetse spp. respond similarly to groups of volatiles derived from the major biosynthetic and catabolic pathways of plants, i.e. to mono- and sesquiterpenes, to lipoxidation products and to aromatics. Mixtures of these plant volatiles also attracted tsetse in the wind tunnel. These findings show that tsetse flies have conserved a strong sensitivity to volatile secondary products of plants, underlining the fundamental role of vegetation in tsetse survival.

Topics: Animals; Chemotaxis; Chromatography, Gas; Flowers; Lantana; Octanols; Odorants; Perception; Pheromones; Plant Leaves; Plant Oils; Polycyclic Sesquiterpenes; Sense Organs; Sesquiterpenes; Smell; Tsetse Flies; Volatilization