Tree canopies are known to emit large amounts of VOCs (volatile organic compounds) such as monoterpenes into the surrounding air. High VOC emission rates from boreal forests have been observed during the transition from winter to summer activity. The most important sources of these are considered to be the green foliage, understory vegetation and soil organisms, but emissions from the living st...

The effects of essential oils isolated from Douglas fir needles on sheep and deer rumen microbial activity were tested by use of an anaerobic manometric technique. Rumen microorganisms were obtained from a sheep which had been fed mainly on alfalfa hay and dried range grass. One deer used in this study had access to Douglas fir trees the year around, whereas the other deer had no access to Doug...

Five new monoterpene indole alkaloids, naucleamides A-E (1-5), were isolated from the bark and wood of Nauclea latifolia, and the structures and relative stereochemistry were elucidated from the spectroscopic data. Naucleamide E (5) is a unique monoterpene indole alkaloid possessing a pentacyclic ring system with an amino acetal bridge.

Chromatographic investigation of the methylene chloride/methanol extract of the aerial parts of Artemisia herba-alba afforded a new monoterpene dimer, in addition to a known monoterpene and three known sesquiterpene lactones. The structures of the compounds were determined by comprehensive NMR analyses, including DEPT, COSY, HMQC, HMBC, and HRMS.

Wild-type tobacco (Nicotiana tabacum) plants emit low levels of terpenoids, particularly from the flowers. By genetic modification of tobacco cv Petit Havana SR1 using three different monoterpene synthases from lemon (Citrus limon L. Burm. f.) and the subsequent combination of these three into one plant by crossings, we show that it is possible to increase the amount and alter the composition o...

family cupressaceae is the largest coniferous plant family. essential oils of many species belonging to family cupressaceae are known to have several biological activities specially antimicrobial activity. the essential oils from aerial parts of calocedrus decurrens torr., cupressus sempervirens stricta l. and tetraclinis articulata (vahl) mast. were prepared by hydrodistillation. the chemical ...

From the aerial parts of Origanum syriacum, three new monoterpene glucosides thymoquinol 2,5-O-beta-diglucopyranoside (3), carvacrol 2-O-beta-glucopyranosyl-(1-->2)-beta-glucopyranoside (4) and p-menth-1-ene-3,4-diol 4-O-beta-glucopyranoside (5) together with two known monoterpene glucosides thymoquinol 2-O-beta-glucopyranoside (1), thymoquinol 5-O-beta-glucopyranoside (2) have been isolated. T...

A Baeyer-Villiger mono-oxygenase (BVMO), catalysing the NADPH- and oxygen-dependent oxidation of the monocyclic monoterpene ketones 1-hydroxy-2-oxolimonene, dihydrocarvone and menthone, was purified to homogeneity from Rhodococcus erythropolis DCL14. Monocyclic monoterpene ketone mono-oxygenase (MMKMO) is a monomeric enzyme of molecular mass 60 kDa. It contains 1 mol of FAD/monomer as the prost...

Four new compounds were isolated from the branches of Piper montealegreanum Yuncker, a shrub found in the Amazon rainforest, including two new dihydrochalcones named claricine (1) and maisine (2), a cinnamic acid derivative 3 and a phenylalkanoid 4, along with a porphyrin identified as the known compound phaeophytin a (5). The structures were established using spectroscopic experiments, includi...

The volatile constituents of drug samples derived from Cannabis sativa L. were investigated by means of headspace solid phase microextraction (HS-SPME) and gas chromatography techniques (GC-MS, GC×GC-MS). Samples of cannabis herb and hashish showed clear differences in their volatile chemical profiles, mostly resulting from photo-oxidation processes occurring during the transformation of fresh ...