the genus hypericum is one of the most important medicinal plants that contain 17 species in iran, three of them are endemics. this paper reports the essential oil composition of six hypericum species from iran. the essential oil analysis of a number of the studied plants has already been reported but their report from iran may be valuable for scientists.  samples collected between june and aug...

When attacked by insects, plants release mixtures of volatile compounds that are beneficial for direct or indirect defense. Natural variation of volatile emissions frequently occurs between and within plant species, but knowledge of the underlying molecular mechanisms is limited. We investigated intraspecific differences of volatile emissions induced from rosette leaves of 27 accessions of Arab...

The chemical composition of volatile oils from 22 genotypes of Citrus and related genera was poorly differentiated, but chemometric techniques have clarified the relationships between the 22 genotypes, and allowed us to understand their resistance to D. citri. The most convincing similarities include the synthesis of (Z)-β-ocimene and (E)-caryophyllene for all 11 genotypes of group A. Genotypes...

Exhaustive hydro-distillation of Descurainia sophia (L.) Webb ex Prantl (flixweed) collected from two different locations (Cangzhou city-Sample 1 and Beijing city-Sample 2) gave in both cases yellowish colored oils in 0.31 and 0.26% yield, respectively. Detailed chemical composition of the essential oils was analyzed by GC and GC/MS, and forty and thirty-eight compounds were identified. The res...

The headspace volatile components of roots, stems, leaves, and flowers of Echinacea angustifolia,E. pallida, and E. purpurea were analyzed by capillary gas chromatography/mass spectrometry (GC/MS). Over 70 compounds were identified in the samples. All plant tissues, irrespective of the species, contain acetaldehyde, dimethyl sulfide, camphene, hexanal, beta-pinene, and limonene. The main headsp...

Chemical composition, antioxidant, antimicrobial and cytotoxic activities of Tagetes minuta (TM) essential oil (TMO) and Ocimum basilicum (OB) essential oil (OBO) were examined. The main components for TMO were dihydrotagetone (33.9%), E-ocimene (19.9%), tagetone (16.1%), cis-β-ocimene (7.9%), Z-ocimene (5.3%), limonene (3.1%) and epoxyocimene (2.03%). The main components for OBO were methylcha...

This investigation aims to assess the chemical composition and antioxidant properties of Origanum vulgare var. aureum L. essential oil (OEO). The was obtained with a 0.34% (v/w dried weight) yield investigated by gas chromatography-mass spectrometry (GC–MS) analysis. main compounds OEO were found be gamma-terpinene (22.96%), para-cymene (14.72%), germacrene (11.64%), beta-trans-ocimene (9.81%),...

The West Bekaa region of Lebanon is mostly an agricultural land where traditional herbal medicine is a common practice. Many medicinal applications are especially attributed to the Citrus aurantium plant mainly used in the food and drink industry. In this work, the essential oil of Citrus aurantium is studied in an attempt to find an explanation for the different medical applications of this pl...

Pulverized rhizome of Curcuma longa on hydrodistilation, afforded oil in the yield of 1.24% v/w. The oil was investigated by GC and GC/MS. Hydrocarbon monoterpenes (46.9%) constituted bulk of the oil. The major constituents of the oil were, $-bisabolene (13.9%), trans-ocimene (9.8%), myrcene (7.6%), 1,8-cineole (6.9%), "-thujene (6.7%) and thymol (6.4%). Key word: Index: curcuma longa % Zingibe...

BACKGROUND In honey bee colony, the brood is able to manipulate and chemically control the workers in order to sustain their own development. A brood ester pheromone produced primarily by old larvae (4 and 5 days old larvae) was first identified as acting as a contact pheromone with specific effects on nurses in the colony. More recently a new volatile brood pheromone has been identified: E-β-o...