摘要:

Cryofocusing GC/FT-IR is a powerful tool for identification of constituents in essential oils. This technique has been used to help identify sesquiterpene hydrocarbons in citrus essential oils that are difficult to identify by GC/MS alone and especially those prone to thermal rearrangements. Bicyclogermacrene is reported for the first time in Sicilian lemon oil and Florida orange and grapefruit. (Z)-α-Bisabolene has been found as a new constituent in Sicilian lemon oil and Mexican cold pressed lime, type A. Germacrene B has been confirmed for the first time in Florida grapefruit oil.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699448

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Sixty-two commercially processed and fresh orange juice samples were analyzed by headspace gas chromatography to quantify 46 volatile constituents in each sample. Computer multivariate analysis was then used to classify these juices into three types based on degree of processing employed. The three types were unpasteurized, pasteurized not from concentrate and reconstituted to single strength from frozen concentrated juice. Principal components (PC) analysis using the first three PC's in a three dimensional graphics plot was the most effective means of classification for these samples. The computer program also provided information regarding the constituents most important to this classification technique. Such classification has potential for use in quality control and in improving quality of processed orange juices.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699449

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Lunasia amaraBlanco var.amarapossessed a leaf oil in 0.1 0.15% yield, in which the principal sesquiterpenes were γ-elemene (0.7–19%), germacrene-D (18–51%) and bicyclogermacrene (7–26%). There were lesser amounts of bicycloelemene (1–2%), β-bourbonene (0.7–3%), β-elemene (4–9%), α-farnesene (1–3%) and δ-cadinene (3–5%).Sarcomelicope simplicifoliasubsp.simplicifolia(Endl.) T.G. Hartley produced a leaf oil, in 0.03–0.1% yield, in which the major compounds were β-caryophyllene (14–22%) and bicyclogermacrene (10–42%). These two sesquiterpenes were accompanied by lesser amounts of α-copaene (1–8%), β-elemene (1–3%), α-humulene (1–4%), δ-cadinene (1–7%), δ-elemene (0.2–2%) and spathulenol (1–5%).

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699450

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

The essential oils extracted from fiveArtabotrysspecies, Annonaceae (A. insignis, A.pierreanus, A. rufus, A. thomsoniandA. venustus) have been examined by GC and GC/MS. The main components of each oil have been identified. Among them, two compounds seem to have a chemotaxonomic significance: cyperenone and 1,5-epoxysalvial-4(l 4)-ene.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699451

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

Essential oils from the leaves and flowering tops ofSalvia glutinosaL. were obtained by hydrodistillation. The oil content was 0.05% (v/w), and 0.03% (v/w), for the leaves and the flowering tops, respectively. The oil composition was determined by GC and GC/MS. Sixty and seventy-four compounds were identified in the oils from leaves and flowering tops, respectively. Both oils were rich in sequiterpenes, with γ-muurolene (15.1–18.7%) as the major component. An antibacterial screening showed that both oils were inactive against Gram (+) and Gram (-) bacteria.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699452

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

The essential oils of tenEucalyptusspecies grown in Rwanda have been examined by GC/MS. More than 100 compounds were characterized in the oils.E. maideniiandE. smithiioils were found to be rich in 1,8-cineole (70–85%),E. divesoil rich in piperitone (33%) andE. macarthuriioil rich in geranyl acetate (50%).

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699453

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

The essential oils ofRosmarinus eriocalyxwhich were produced from the leaves of six populations of plants collected in Algeria under different ecological conditions were analysed by GC and GC/MS. InR. eriocalyx36 compounds were identified, with camphor (32.3–37.0%), camphene (17.0–20.0%), a-pinene (15.2–18.2%) and 1,8-cineole (7.6–11.4%) as main components in all samples. In order to permit comparison, analyses were also conducted on the essential oil ofR. officinalisfrom Spain and Italy. Also in this case the principal component was camphor (35.3% and 17.7%), followed by 1,8-cineole (24.0% and 23.5%) and limonene (11.0% and 9.5%). It has been demonstrated that quantitative differences in α-pinene, β-pinene, 1,8-cineole and camphor exist when our results are compared with these previously published.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699454

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

The essential oils obtained by hydrodistillation from the fresh flowers and fruits ofPersea bombycina(King ex Hook. f.) Kost (previously calledMachilus bombycinaKing) were examined by a combination of high resolution GC and GC/MS. The flower oil contained more than 65 compounds of which the major constituents were found to be caryophyllene oxide (19.4%), (E)-nerolidol (14.5%), 11-dodecenal (11.2%) and 11-dodecenoic acid (9.8%). The composition of the fruit oil was entirely different. Among the more than 60 (mostly oxygenated) constituents, the furanoid forms of trans- (8.0%) and cis-linalool oxide (7.3%) were major components, but many compounds could not be identified.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699455

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

The composition of the oil and volatile concentrate isolated from Mexican pimento berries (Pimenta dioicaMerrill) was studied. The oil was obtained by steam distillation, by hydrodistillation and the volatile concentrate by supercritical carbon dioxide. The oil was analyzed by GC and by GC/MS. Twenty-five compounds were identified, including sabinene and methyl salicylate for the first time. Methyl eugenol (48.3–67.9%) was the main component of the oil.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699456

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor

摘要:

The yield and composition of sage (Salvia officinalisL.) oil cultivated in northern Italy and subjected to different growing conditions (planting densities and harvest managements) were evaluated. Sage harvested in spring at flowering stage (1st cut) gave the highest yields of fresh and dried matter. A harvesting regimen with three successive harvests produced the highest biomass yield. Twenty-nine compounds were identified in the oil. The oil of sage harvested at flowering stage greatly differed in composition from the oil of sage cut at vegetative stage. Very important differences were observed also between the oil composition of sage harvested at vegetative stage in spring and in the autumn. The highest content of thujones was found in the oils of sage harvested in autumn.

ISSN:1041-2905    

DOI:10.1080/10412905.1997.9699457

出版商:Taylor & Francis Group    

年代:1997

数据来源: Taylor