摘要:

AbstractThe essential oil obtained by steam distillation from the dried leaves ofAchillea abrotanoides(Vis.) Vis. was analysed by a combination of capillary gas chromatography (CGC), capillary gas chromatography ‐ mass spectrometry (CGC‐MS) and capillary gas chromatography ‐ Fourier transform/infrared spectroscopy (CGC‐FT/ IR). 1,8‐Cineole and camphor accounted for about 32.7% of the oil which contained about fifty compounds most of them present only in traces; 24 components (92.3% of the oil) were char

ISSN:0882-5734    

DOI:10.1002/ffj.2730030302

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractSawdust waste of Mulanje cedarwood (Widdringtonia whyteiRendle) from Malawi affords on steam‐distillation a yield of approximately 10ml of essential oil per 100g of moisture‐free sawdust (10%v/m). Raw material availability would permit the production of some 900kg of oilper annumin Malawi. The constituents of the Mulanje oil include thujopsene (32%), cedrol (ca 13%), α‐cedrene (2%), widdrol (ca 5%), thujopsadiene (7%) and cuparene (4%). The oil differs from Virginian cedarwood oil in both composition and aroma cha

ISSN:0882-5734    

DOI:10.1002/ffj.2730030303

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe flavour composition of dragonhead (Dracocephalum moldavicaL.) was analysed by capillary gas chromatography ‐ mass spectrometry. Altogether 57 compounds were identified and 11 unknown components detected. The volatile oil of dragonhead consists mainly of oxygenated, acyclic monoterpenes; geranyl acetate, geranial, neral, geraniol and neryl acetate together account for about 90% of the oil. Monoterpene hydrocarbons are present only in trace amounts. The compounds which could not be identified are oxygenated monoterpenes, oxygenated sesquiterpenes, one sesquiterpene hydrocarbon and a mixture of an oxygenated monoterpene and a sesquiterpene hydrocarbo

ISSN:0882-5734    

DOI:10.1002/ffj.2730030304

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe essential oil from dragonhead,Dracocephalum moldavicaL., was studied with special attention being paid to the yield of oil and how the amount of the main components changes during the vegetative period. The oil reaches its maximum level during the flowering, as is also the case with geranyl acetate, geranial and geraniol. The content of neral, however, decreases during flowering. These observations indicate that the biosynthesis of geranyl acetate is dominant at the beginning of the vegetative period, but is superseded by biosynthesis of geranial and geraniol, from the early stage of flowering. The optimum harvest time proved to be during the flowering stage, when the oil content is highest and thus also the amount of the main terpenes is highest.

ISSN:0882-5734    

DOI:10.1002/ffj.2730030305

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractChiral alcohols and acetates were isolated with high chemical purities from various essential oils. The enantiomeric purities of the chiral oxygenated terpenes were compared with the synthetic racemic terpenes by1H‐NMR ‘polarimetry’ in the presence of various molar ratios of a chiral lanthanide shift reagent, Eu(hfc)3. The singlet methyl resonance of the acetate in the1H‐NMR spectra is more helpful than the other resolved resonances of the alcohols in determining the enantiomeric purity. Efforts to use Eu(hfc)3to determine the enantiomeric composition of 4‐substituted γ‐lactones were no

ISSN:0882-5734    

DOI:10.1002/ffj.2730030306

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractThe essential oil of freeze‐dried dill herb was isolated by hydrodistillation, solvent extraction, and CO2‐extraction and analysed by combination of GLC‐MS. Head‐space gas chromatography (HSGC) was also used for analysing dill volatiles. Fifty compounds were detected, but only the ten main components were chosen to facilitate the comparison of the methods. Each method gave a different composition for the volatiles of the dill herb. However, the best result was achieved by HSGC, in that the yield of 3,6‐dimethyl‐2,3,3a, 4,5,7a‐hexahydrobenzofuran, the most important aroma compound of the dill herb, was highest with HSGC. Hydrodistillation also was a reproducible and convenient method for analysi

ISSN:0882-5734    

DOI:10.1002/ffj.2730030307

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

摘要:

AbstractAdulteration of cold‐pressed oil of the lemonCitrus limonwith the lower quality steam‐stripped oil still occurs on a major scale. It has been known for many years that substances with ultraviolet absorption characteristics similar to those of the coumarins and psoralens present naturally in cold‐pressed lemon oil are added to the oil mixture to mask the adulteration. The present work has confirmed that substances such as ethyl p‐dimethylaminobenzoate and 7‐geranyloxycoumarin (auraptene) are still used to conceal the adulteration of cold‐pressed lemon oil. 7‐Methoxycoumarin (herniarin) and 5,7‐dipropyloxy‐4‐methylcoumarin were also identified in certain commercial lemon oil samples. These compounds are not natural components of lemon oil and have not been associated previously with its adulteration.A novel 5,8‐disubstituted psoralen was detected in authentic cold‐pressed lemon oil and identified as 5‐isopent‐2′‐enyloxy‐8‐(2′,3′‐epoxyisopentyloxy)psoralen(1). The concentrations of the natural coumarins and ps

ISSN:0882-5734    

DOI:10.1002/ffj.2730030308

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

ISSN:0882-5734    

DOI:10.1002/ffj.2730030309

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

ISSN:0882-5734    

DOI:10.1002/ffj.2730030310

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY

ISSN:0882-5734    

DOI:10.1002/ffj.2730030311

出版商:John Wiley&Sons, Ltd.    

年代:1988

数据来源: WILEY