caryophyllene and thujopsene

Bearded irises are ornamental plants with distinctive floral fragrance grown worldwide. To identify the floral scent profiles, twenty-seven accessions derived from three bearded iris, including

Topics: Acyclic Monoterpenes; Flowers; Gas Chromatography-Mass Spectrometry; Iris Plant; Monoterpenes; Odorants; Perfume; Polycyclic Sesquiterpenes; Sesquiterpenes; Solid Phase Microextraction; Terpenes; Volatile Organic Compounds

Patchouli is used as an incense material and essential oil. The characteristic odor of patchouli leaves results from the drying process used in their production; however, there have to date been no reports on the changes in the odor of patchouli leaves during the drying process. We investigated the aroma profile of dried patchouli leaves using the hexane extracts of fresh and dried patchouli leaves. We focused on the presence or absence of the constituents of the fresh and dried extracts, and the differences in the content of the common constituents. Fourteen constituents were identified as characteristic of dried patchouli extract odor by gas chromatography-olfactometry analysis. The structures of seven of the 14 constituents were determined by gas chromatography-mass spectrometry (α-patchoulene, seychellene, humulene, α-bulnesene, isoaromadendrene epoxide, caryophyllene oxide, and patchouli alcohol). The aroma profile of the essential oil obtained from the dried patchouli leaves was clearly different from that of dried patchouli. The aroma profile of the essential oil was investigated by a similar method. We identified 12 compounds as important odor constituents. The structures of nine of the 12 constituents were determined by gas chromatography-mass spectrometry (cis-thujopsene, caryophyllene, α-guaiene, α-patchoulene, seychellene, α-bulnesene, isoaromadendrene epoxide, patchouli alcohol, and corymbolone). Comparing the odors and constituents demonstrated that the aroma profile of patchouli depends on the manufacturing process.

Topics: Azulenes; Chromatography, Gas; Gas Chromatography-Mass Spectrometry; Hexanes; Liquid-Liquid Extraction; Odorants; Oils, Volatile; Olfactometry; Plant Extracts; Plant Leaves; Plant Oils; Pogostemon; Polycyclic Sesquiterpenes; Sesquiterpenes; Sesquiterpenes, Guaiane; Terpenes

E-(β)-caryophyllene is a sesquiterpene volatile emitted by plants and involved in many ecological interactions within and among trophic levels and it has a kairomonal activity for many insect species. In grapevine it is a key compound for host-plant recognition by the European grapevine moth, Lobesia botrana, together with other two sesquiterpenes. In grapevine E-(β)-caryophyllene synthase is coded by the VvGwECar2 gene, although complete characterization of the corresponding protein has not yet been achieved. Here we performed the characterization of the enzyme after heterologous expression in E. coli, which resulted to produce in vitro also minor amounts of the isomer α-humulene and of germacrene D. The pH optimum was estimated to be 7.8, and the K

Topics: Alkyl and Aryl Transferases; Arabidopsis; Escherichia coli; Monocyclic Sesquiterpenes; Polycyclic Sesquiterpenes; Polyisoprenyl Phosphates; Sesquiterpenes; Stereoisomerism; Vitis; Volatile Organic Compounds