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1.
The chemical composition of the essential oils obtained from the leaves, the barks of the stem and the root, as well as from the fresh and dried fruits of Xylopia aethiopica, growing in Ghana, was investigated by gas chromatography/mass spectrometry analyses. Kovats indices, mass spectra, and standard compounds were used to identify a total of 93 individual compounds. The monoterpene hydrocarbons formed the main portion in all studied samples. beta-Pinene was predominant in all cases, while trans-m-mentha-1(7),8-diene was the main compound in the essential oils of the leaves and the barks of roots and stems. Their potential antioxidant activity was also investigated and found to be significant in scavenging superoxide anion radical.  相似文献   

2.
The volatile constituents of cold-pressed peel essential oils of redblush grapefruit (Citrus paradisi Macfadyen forma Redblush) and pummelo (Citrus grandis Osbeck) from the same locality in Kenya were determined by GC and GC-MS. A total of 67 and 52 compounds, amounting to 97.9 and 98.8% of the two oils, respectively, were identified. Monoterpene hydrocarbons constituted 93.3 and 97.5% in the oils, respectively, with limonene (91.1 and 94.8%), alpha-terpinene (1.3 and 1.8%), and alpha-pinene (0.5%) as the main compounds. Sesquiterpene hydrocarbons constituted 0.4% in each oil. The notable compounds were beta-caryophyllene, alpha-cubebene, and (E,E)-alpha-farnesene. Oxygenated compounds constituted 4.2 and 2.0% of the redblush grapefruit and pummelo oils, respectively, out of which carbonyl compounds (2.0 and 1.3%), alcohols (1.4 and 0.3%), and esters (0.7 and 0.4%) were the major groups. Heptyl acetate, octanal, decanal, citronellal, and (Z)-carvone were the main constituents (0.1-0.5%). Perillene, (E)-carveol, and perillyl acetate occurred in the redblush grapefruit but were absent from the pummelo oil. Nootkatone, alpha- and beta-sinensal, methyl-N-methylanthranilate, and (Z,E)-farnesol were prominent in both oils.  相似文献   

3.
Essential oils from the stems/leaves (L) and flowers (F) of Lavandula stoechas L. ssp. stoechas growing wild in southern Sardinia (Italy) were extracted by hydrodistillation and analyzed by gas chromatography coupled with flame ionization detector and ion trap mass spectrometry. The major compound was fenchone, accounting for, on average, 52.60% in L and 66.20% in F, followed by camphor (13.13% versus 27.08%, in L and F, respectively). F essential oil yields (volume per dry weight) decreased from the beginning to the end of the flowering stage, whereas L yields remained constant during the year. The nine main compounds derived from two different subpathways, A and B. The compounds that belong to the same subpathway showed a similar behavior during the year. The essential oils were tested for their antifungal activity using the paper disk diffusion method. The essential oils tested were effective on the inactivation of Rhizoctonia solani and Fusarium oxysporum and less effective against Aspergillus flavus. Among the single compounds tested, fenchone, limonene, and myrtenal appeared to be the more effective on the inhibition of R. solani growth.  相似文献   

4.
The essential oils from aerial and root parts of Glehnia littoralis were investigated by GC and GC-MS, and 125 compounds were identified. Plants were obtained from Northern and Southern Japan, and samples from the same locations were cultivated either exposed or unexposed to sunlight. The main constituents of the essential oils were found to be alpha-pinene (0.03-13.40%), limonene (0.15-10.71%), beta-phellandrene (0.03-22.93%), germacrene B (0.27-8.33%), spathulenol (0.24-6.50%), beta-oplopenone (0.06-6.47%), panaxynol (0.38-24.58%), propyl octanoate (3.44-27.85%), hexadecanoic acid (0.45-27.80%), and linoleic acid (0.16-17.56%). Terpenoid compounds were found in higher concentrations in the Northern type oils than in the Southern types, whereas the concentration of polyacetylenic compounds was higher in one of the Southern samples, except from the aerial parts of those cultivated exposed. Consequently, the constitution of the essential oils from G. littoralis could be separated into Northern and Southern types.  相似文献   

5.
The isolated essential oils from seven air-dried plant species were analyzed by gas chromatography-mass spectrometry (GC-MS). Thymus vulgaris (thyme), Origanum vulgare (oregano), and Origanumdictamus (dictamus) essential oils were found to be rich in phenolic compounds representing 65.8, 71.1, and 78.0% of the total oil, respectively. Origanum majorana (marjoram) oil was constituted of hydrocarbons (42.1%), alcohols (24.3%), and phenols (14.2%). The essential oil from Lavandula angustifolia Mill. (lavender) was characterized by the presence of alcohols (58.8%) and esters (32.7%). Ethers predominated in Rosmarinus officinalis (rosemary) and Salvia fruticosa (sage) essential oils, constituting 88.9 and 78.0%, respectively. The radial growth, conidial germination, and production of Penicillium digitatum were inhibited completely by oregano, thyme, dictamus, and marjoram essential oils at relatively low concentrations (250-400 microg/mL). Lavender, rosemary, and sage essential oils presented less inhibitory effect on the radial growth and conidial germination of P. digitatum. Conidial production of P. digitatum was not affected by the above oils at concentrations up to 1000 microg/mL. Apart from oregano oil, all essential oils were more effective in the inhibition of conidial germination than of radial growth. The monoterpene components, which participate in essential oils in different compositions, seem to have more than an additive effect in fungal inhibition.  相似文献   

6.
Major short-chain glycerol-bound compounds were investigated in olive oil (OO) and conventional sunflower oil (SO) during thermoxidation at 180 degrees C for 5, 10, and 15 h. These compounds included methyl heptanoate (C7:0), methyl octanoate (C8:0), methyl 8-oxo-octanoate (8-oxo-C8:0), methyl 9-oxononanoate (9-oxo-C9:0), dimethyl octanodiate (C8:0 diester), and dimethyl nonanodiate (C9:0 diester), which were analyzed by GC after derivatization of triacylglycerols to fatty acid methyl esters. An acceptable linear correlation (r = 0.967) was found between the total content of these compounds and the total content of polar compounds, suggesting that quantitation of the major short-chain glycerol-bound compounds provides a good indication of the total alteration level of oils heated at frying temperature. Samples with levels of polar compounds around 25% on oil showed total contents within 2-3 mg/g of oil. To determine the content of these compounds in used frying oils, 10 samples from restaurants and fried-food outlets in Spain were analyzed. Results showed total levels between 2.13 and 7.56 mg/g of oil in samples with contents of polar compounds ranging from 18.8 to 55.5% on oil. Samples with levels of polar compounds of approximately 25% showed total contents of the short-chain compounds similar to those found in the thermoxidized oils, that is, within 2-3 mg/g of oil.  相似文献   

7.
The composition of the essential oil of Citrus tamurana Hort. ex Tanaka (Hyuganatsu), isolated by the cold-pressing method, was investigated by capillary GC and GC-MS. The effects of harvesting time, degree of freshness, and size of fruits on the composition of Hyuganatsu peel oils were also determined. A total of 126 volatile constituents were confirmed in the Hyuganatsu oils. The Hyuganatsu oils contained hydrocarbons (95.95-96.95%), aldehydes (0.33-0.62%), alcohols (1.91%-2.64%), ketones (0.40-0.62%), esters (0.28-0.39%), oxides (0.04-0.06%), acids (0.01%), and trace amounts of fugenol methyl ether. Monoterpene hydrocarbons were predominant. Limonene (80.35-82.39%), gamma-terpinene (7.71-9.03%), myrcene (2.11-2.28%), linalol (1.37-2.01%), and alpha-pinene (1.17-1.43%) were the most abundant components in Hyuganatsu oils. The principal sesquiterpene hydrocarbon was trans-beta-farnesene (0.60-1.04%), and its content in Hyuganatsu oils was higher than in oils of other citrus fruits. The number of ketones and the content of l-carvone in Hyuganatsu oils were higher than in other citrus oils.  相似文献   

8.
Thirteen essential oils were examined for their antioxidant activity using three different assay systems. Jasmine, parsley seed, rose, and ylang-ylang oils inhibited hexanal oxidation by over 95% after 40 days at a level of 500 microg/mL in the aldehyde/carboxylic acid assay. Scavenging abilities of the oils for the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical ranged from 39% for angelica seed oil to 90% for jasmine oil at a level of 200 microg/mL. The greatest inhibitory activity toward malonaldehyde (MA) formation from squalene upon UV-irradiation was obtained from parsley seed oil (inhibitory effect, 67%), followed by rose oil (46%), and celery seed oil (23%) at the level of 500 microg/mL. The main compounds of oils showing high antioxidant activity were limonene (composition, 74.6%) in celery seed, benzyl acetate (22.9%) in jasmine, alpha-pinene (33.7%) in juniper berry, myristicin (44%) in parsley seed, patchouli alcohol (28.8%) in patchouli, citronellol (34.2%) in rose, and germacrene (19.1%) in ylang-ylang.  相似文献   

9.
The volatile composition of the essential oils from leaves and roots of Eupatorium betonicaeforme (D.C.) Baker was analyzed by GC-MS. A total of 12 compounds were identified. beta-Caryophyllene (12.4-41.7%), alpha-humulene (11.7-14.6%), gamma-muurolene (10.4-19.0%), bicyclogermacrene (15.0-17.5%), 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%), and 2-senecioyl-4-vinylphenol (8.5-41.0%) were the most prominent constituents. The former two compounds were isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti larvae survival. The results obtained show that the essential oil from roots and 2,2-dimethyl-6-vinylchroman-4-one (10.3-25.5%) could be considered as natural larvicidal agents.  相似文献   

10.
The productive potential of two different ecotypes of Rosmarinus officinalis (Cevoli and Lunigiana) cultivated in the littoral area near Pisa (northern Tuscany, Italy) and the differences in the yield and composition of the essential oils of leaves, flowers, and stems obtained from different positions of the plants were used to characterize the two ecotypes. The Cevoli ecotype plant produced the highest yield of dry matter (221 g plant-1) in comparison to the Lunigiana ecotype (72 g plant-1). There were significant differences in dry matter production of different organs of both ecotypes. The essential oil contents of Cevoli and Lunigiana ecotypes were similar. In contrast, the oil contents of the different plant parts showed marked differences. The apical part of the plant and the leaves gave the highest essential oil yields. The major difference between the oils of the two ecotypes consisted in the 1,8-cineole contents (6.6 and 37.9% in Cevoli and Lunigiana, respectively). The Cevoli ecotype was determined to be the most suitable for essential oil extraction because it was characterized by a preponderance of flowers and leaves in the apical portion. The Cevoli ecotype could be classifited as an alpha-pinene chemotype, whereas Lunigiana is a 1,8-cineole chemotype.  相似文献   

11.
The chemical composition of the volatile fraction of myrtle (Myrtus communis L.) alcoholic extracts and essential oils from leaves and berries collected in different places in Sardinia (Italy) was studied. A simple and rapid liquid-liquid extraction method was used to isolate volatile compounds from myrtle alcoholic extracts followed by GC and GC-MS analysis allowing the detection of 24 compounds. The volatile fraction was characterized by the terpenes fraction corresponding to that of the essential oils and by a fatty acid ethyl esters fraction. The variation during extraction of the volatile fraction in alcoholic extracts of berries and leaves was evaluated. Essential oils were obtained by hydrodistillation, and the yields were on average 0.52 +/- 0.03% (v/w dried weight) and 0.02 +/- 0.00% for leaves and berries, respectively. The essential oils were analyzed by GC and GC-MS, and a total of 27 components were detected, accounting for 90.6-98.7% of the total essential oil composition. Strong chemical variability depending on the origin of the samples was observed. The major compounds in the essential oils were alpha-pinene (30.0 and 28.5%), 1,8-cineole (28.8 and 15.3%), and limonene (17.5 and 24.1%) in leaves and berries, respectively, and were characterized by the lack of myrtenyl acetate.  相似文献   

12.
A protocol based on the use of horseradish peroxidase (HRP) is proposed for the removal of allergenic eugenol from rose essential oil without loss of the organoleptic quality and with a good conservation of the chemical composition. For the first time, an enzyme-based strategy is proposed for essential oils treatment and opens new opportunities in the detoxification of natural extracts used in perfumery and cosmetics. Our results on eugenol in rose essential oil constitute a first step toward the development of efficient and mild processes for the removal of more toxic compounds of natural extracts.  相似文献   

13.
The effect of the essential oils of thyme on the in vitro ruminal degradability of a barley seed/alfalfa hay substrate was studied. Two essential oils were used, one from Thymus hyemalis (TH), rich in carvacrol, and the other from Thymus zygis (TZ), rich in thymol. Four experimental treatments of in vitro degradability, using the Daisy II(200/220) incubator, were conducted including a negative control (CO), a positive control at 7.5 microg/mL of monensin (MO), and two treatments with essential oils (TH or TZ) at 1.35 microL/mL. The material was incubated at 39.5 degrees C for various lengths of time. At each time, the disappearance of dry matter, crude protein, and neutral detergent fiber was measured. Volatile fatty acids (VFAs) were determined after 48 h of incubation. CO and MO provided (p < 0.01) higher values of potential degradability (a + b) of DM than the TH and TZ treatments (72.6 and 70.8 vs 53.2 and 48.2%, respectively). Also, crude protein degradability was lowest in the essential oil treatments. The CO treatment showed the highest potential degradability of NDF. The values of VFA production obtained (p < 0.001) with CO and MO treatments were higher than those obtained with TH and TZ treatments (21.0 and 19.1 vs 11.2 and 10.1 mM). The essential oils decreased the molar proportion of propionate, increasing the acetate/propionate ratio. In conclusion, the effects of essential oils at assayed doses would not be nutritionally beneficial to the ruminal energetic metabolism.  相似文献   

14.
To determine the effects of chromium (Cr) supplementations on oxidative stress of type 2 diabetes and euglycemic (EU) subjects, adult having HbA(1C) values of <6.0% (EU), 6.8-8.5% (mildly hyperglycemic, MH), and >8.5% (severely hyperglycemic, SH) were supplemented for 6 months with 1000 microg/day of Cr (as Cr yeast) or with a placebo. In the beginning, the levels of the plasma Cr in the MH and SH groups were 25-30% lower than those of the EU subjects. The values of thiobarbituric acid reactive substances (TBARS) and total antioxidative status (TAS) of the MH and SH groups were significantly higher than those of the EU ones. Following supplementations, the levels of plasma TBARS in the Cr groups of MH and SH groups were significantly decreased (the inverse was found in the EU) and showed no significant changes in the placebo group. The levels of plasma TAS in the Cr groups of EU and MH were significantly decreased (the inverse was found in the SH) and showed no significant changes in the placebo group. No significant difference was found in the antioxidant enzyme (superoxide dismutase, glutathione peroxidase, catalase) activities during supplementations. These data suggest that Cr supplementation was an effective treatment strategy to minimize increased oxidative stress in type 2 diabetes mellitus patients whose HbA(1C) level was >8.5%, and the Cr in EU groups might act as a prooxidant.  相似文献   

15.
In vitro shoots of sage (Salvia officinalis L.) were established under eight different hormonal supplementations and proliferated by subculture of nodal shoot segments. The respective essential oils, obtained by hydrodistillation, were composed of more than 75 compounds, 65 of which were identified. The 10 major compounds were, by order of retention time, alpha-pinene (4.1-5.4%), camphene (6-7.1%), beta-pinene (9.3-14.5%), limonene (2-2.3%), 1,8-cineole (3.6-5.6%), (-)-thujone (13.2-16.1%), (+)-isothujone (6.6-7.4%), camphor (19.8-24%), alpha-humulene (5.1-6.8%), and manool (4.2-7.7%). Notwithstanding the eight different hormonal supplementations tested, the percentage composition of the shoot essential oils were kept in a narrow range of variation. However, the type and concentration of growth regulators apparently influenced the accumulation of essential oils. The highest accumulation of essential oils and the highest shoot biomass growth were obtained with 2.0 mg/L kinetin and 0.05 mg/L 2,4-dichlorophenoxyacetic acid.  相似文献   

16.
The fresh yields, the essential oil content, and the quality of a sage hybrid (Salvia officinalis x Salvia fruticosa, cv. Newe Ya'ar No. 4, Lamiaceae) as affected by development and harvest time were determined. Marked increases in plant height and in the number of nodes developed per plant together with a modest increase in leaf size were accompanied by dramatic increases (more than 20-fold) in the fresh yields throughout a 50-day growth period. No major changes in the essential oil content per fresh weight and its composition were detected throughout the growth period. In contrast, the compositions of the essential oils obtained from stems, as compared to leaves and leaf-primordia, had marked differences. Developmentally controlled changes in the extractives from individual leaf pairs from the same plant were also noted. In upper young leaves, the oxygenated diterpene manool and the sesquiterpene hydrocarbons alpha-humulene and beta-caryophyllene constituted up to 20%, 8%, and 4% of the total extractives, respectively. In older leaves, the abundance of these components steadily dropped to roughly half their levels in young leaves. Conversely, the proportions of the monoterpenes, particularly the ketones camphor and alpha-thujone, steadily increased with leaf position. Minor changes in the levels of other extractives were also recorded. These studies imply independent regulatory patterns for di-, sesqui-, and monoterpenes in this sage hybrid, and suggest possible agrotechnical means to obtain preferred chemical compositions of its essential oil.  相似文献   

17.
The compositions of essential oils isolated from the aerial parts of Artemisia absinthium, Artemisia santonicum, and Artemisia spicigera by hydrodistillation were analyzed by GC-MS, and a total of 204 components were identified. The major components of these essential oils were camphor (34.9-1.4%), 1,8-cineole (9.5-1.5%), chamazulene (17.8-nd%), nuciferol propionate (5.1-nd%), nuciferol butanoate (8.2-nd%), caryophyllene oxide (4.3-1.7%), borneol (5.1-0.6%), alpha-terpineol (4.1-1.6%), spathulenol (3.7-1.3%), cubenol (4.2-0.1%), beta-eudesmol (7.2-0.6%), and terpinen-4-ol (3.5-1.2%). The antifungal activities of these essential oils were tested against 11 plant fungi and were compared with that of a commercial antifungal reagent, benomyl. The results showed that all of the oils have potent inhibitory effects at very broad spectrum against all of the tested fungi. Pure camphor and 1,8-cineole, which are the major components of the oils, were also tested for antifungal activity against the same fungal species. Unlike essential oils, these pure compounds were able to show antifungal activity against only some of the fungal species. In addition, the antioxidant and DPPH radical scavenging activities of the essential oils, camphor, and 1,8-cineole were determined in vitro. All of the studied essential oils showed antioxidant activity, but camphor and 1,8-cineole did not.  相似文献   

18.
The essential oil yields obtained by hydrodistillation of the aerial parts of Hypericum androsaemum cultivated plants varied from 0.94 to 4.09 mg/g of biomass dry weight, depending of the harvest time. The respective analyses performed by gas chromatography and gas chromatography-mass spectrometry revealed more than 80 compounds, 72 of which were identified. Most of the compounds were sesquiterpene hydrocarbons, which, depending of the harvest time, corresponded to 43-78% of the total essential oil. The other compounds were distributed as monoterpene hydrocarbons, oxygen-containing sesquiterpenes, n-alkanes, 1-alkenes, and oxygen-containing monoterpenes, these being a minor group. In H. androsaemum in vitro shoots, sesquiterpene hydrocarbons represented >80% of the respective essential oil. Differences in the essential oil composition were found depending on the harvest time and origin, in vivo versus in vitro, of the plant material. The essential oil sampled in November was characterized by the highest levels of sesquiterpene hydrocarbons and a high number of n-alkanes and 1-alkenes, from C(18) to C(28), whereas that sampled in June of the following year showed the highest levels of n-nonane and 1-octene as well as monoterpene hydrocarbons, the second most representative group.  相似文献   

19.
The essential oils from leaves and flowers of costmary, Balsamita major (L.) Desf. (syn. Chrysanthemum balsamita L.), were analyzed at various phases of plant growth. The highest contents of oil both in leaves and in flowers were determined before full blooming, 1.15 and 1.34% (w/w), respectively. Seventy-eight volatile compounds have been identified in the oils of Balsamita major, of which 58 (19 tentatively, 39 positively) have not been reported in this plant previously. Carvone and alpha-thujone were found to be dominating compounds constituting from 51.8 to 68.0% and from 9.0 to 16.1% in the total oil, respectively. Seasonal variations in the oil compositions were not considerable except for the starting phase (May 25, 1995), when the content of carvone was lower and the content of alpha-thujone and sesquiterpenes higher. The content of sesquiterpenes was approximately 2 times higher in flowers than in the leaves. Absolute amount of most components was highest at the bud formation period.  相似文献   

20.
The hydrodistilled essential oils of the aerial parts of wild-growing Salvia sclarea originated from two localities in Greece were analyzed by GC-MS. Sixty-six compounds, representing 93.26-98.19% of the oils, were identified. Linalyl acetate (19.75-31.05%), linalool (18.46-30.43%), geranyl acetate (4.45-12.1%), and alpha-terpineol (5.08-7.56%) were the main components. The antifungal activity of the oil of one locality and of the main components, linalyl acetate and linalool, was evaluated in vitro against three soil-borne pathogens.  相似文献   

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