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1.
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   

2.
The composition of the essential oils of Origanum and Thymus species restricted to Algeria and the North Africa region was determined. Antioxidant and antibacterial activities of the isolated essential oils were also determined. The oils of oregano plants were strongly characterized by p-cymene (16.8-24.9%), gamma-terpinene (16.8-24.9%), thymol (8.4-36.0%), and carvacrol (1.1-29.7%), a thymol chemotype for Origanum floribundum and a alpha-terpineol chemotype for Thymus numidicus being described for the first time. The strains of Listeria monocytogenes tested were relatively resistant to the action of essential oils of either Origanum or Thymus species. All essential oils possessed antioxidant activity, but this was dependent on the specific chemical composition and the method employed to determine such activity.  相似文献   

3.
Fish oils extracted from marinated herring (frozen and unfrozen) byproducts and maatjes herring byproducts were evaluated on their chemical and sensory properties. The obtained crude oils had very low content of copper (<0.1 mg/kg oil), and iron values were 0.8, 0.1, and 0.03 mg/kg oil, respectively, for oil from maatjes and frozen and fresh byproducts. For the maatjes oil, a much lower value was found for alpha-tocopherol compared to the other oils. Storage stability results showed that the oils behave differently. Secondary oxidation products were measured for fresh oil, while for the maatjes and frozen byproducts' oil, tertiary oxidation products were detected. Over storage time, the maatjes and frozen byproducts' oils became more intense in odor, correlating positively at the end with sensory attributes of train-oil, acidic, marine and fishy. The best correlation between sensory and chemical analyses was found for FFA and fishy off-odor (r = 0.781).  相似文献   

4.
A field experiment was conducted to assess yield, oil content, and composition of 38 genotypes of sweet basil ( Ocimum basilicum L.). Overall, biomass yields were high and comparable to those reported in the literature. However, basil genotypes differed significantly with respect to oil content and composition. Oil content of the tested accessions varied from 0.07% to 1.92% in dry herbage. On the basis of the oil composition, basil accessions were divided into seven groups: (1) high-linalool chemotype [19-73% (-)-linalool], (2) linalool-eugenol chemotype [six chemotypes with 28-66% (-)-linalool and 5-29% eugenol], (3) methyl chavicol chemotype [six accessions with 20-72% methyl chavicol and no (-)-linalool], (4) methyl chavicol-linalool chemotype [six accessions with 8-29% methyl chavicol and 8-53% (-)-linalool], (5) methyl eugenol-linalool chemotype [two accessions with 37% and 91% methyl eugenol and 60% and 15% (-)-linalool], (6) methyl cinnamate-linalool chemotype [one accession with 9.7% methyl cinnamate and 31% (-)-linalool], and (7) bergamotene chemotype [one accession with bergamotene as major constituent, 5% eucalyptol, and <1% (-)-linalool]. Our results demonstrated that basil could be a viable essential oil crop in Mississippi. The availability of various chemotypes offers the opportunity for production of basil to meet the market requirements of specific basil oils or individual compounds such as (-)-linalool, eugenol, methyl chavicol, methyl cinnamate, or methyl eugenol.  相似文献   

5.
The chemical composition of the essential oils obtained from leaves and bracts of hydroponically cultivated Origanum dictamnus L. (Cretan dittany), growing under various electrical conductivity (EC) levels (2.0, 4.0, and 6.0 mS/cm), was studied, using the nutrient film technique (NFT). The analysis of the essential oil content was achieved by GC-MS technique, and totals of 41 and 38 different compounds were identified in both cases of large-leaved and narrow-leaved samples of leaves and bracts, respectively. Differences in the composition content and of the percentage of each of the constituents in the two studied samples (i.e., large-leaved and narrow-leaved) and within the essential oils of leaves and bracts in both samples were observed. Carvacrol and p-cymene were identified as the main constituents in all essential oils, whereas thymoquinone was found in higher percentage in the essential oils of large-leaved than in narrow-leaved plants. The results obtained from GC-MS analysis were submitted to chemometric analysis, and a phenotypic similarity of the essential oils of narrow-leaved O. dictamnus was observed, whereas the essential oils of large-leaved O. dictamnus showed two separate subgroups.  相似文献   

6.
Kuwait's desert was inundated, in 1991, with massiveoil-spills from damaged well heads and from oil fires.Large volumes of seawater used for fire-fightingfreely mixed with oil and then seeped into the ground.The dissolved compounds not only contaminated soil butalso threaten to pollute groundwater. The compositionof the volatile organic compounds (VOCs) in thewater-soluble fraction (WSF), in seawater, of tendifferent crude oils produced in Kuwait and Kuwaitcrude oil (export) was investigated. The resultsshowed that the composition of the WSFs variedconsiderably (ranging from 5970 μg L-1 to10494 μg L-1). On average, about 40 volatilecompounds were identified and quantified in the WSFs.Aromatics formed the bulk of the WSF of all of thecrude oils, amounting to about 90% of the total VOCs.The WSF prepared from Raudatain crude oil containedthe highest total VOCs (benzene and toluene) whilethat of Um-Ghadair contained the lowest. The WSF ofKuwait crude oil (export) was compared with that ofindividual oils and was found to contain relativelysmaller amounts of individual components and the VOCs.Relatively higher amounts of toxic VOCs in the WSF ofRaudatain crude oil has potential to impact the fonaand flora as well as potable ground water in the area.  相似文献   

7.
The chemical composition of essential oils from aerial parts of Thymus spinulosus Ten. (Lamiaceae) is reported. Four oils from plants growing in different environmental conditions were characterized by GC and GC-MS methods; the oils seem to indicate a new chemotype in the genus Thymus. Influences of soil and altitude characteristics on the essential oil composition are discussed. The oils showed antibacterial activity against Gram-positive (Staphylococcus aureus, Streptococcus faecalis, Bacillus subtilis, and Bacillus cereus) and Gram-negative (Proteus mirabilis, Escherichia coli, Salmonella typhimuium Ty2, and Pseudomonas aeruginosa) bacteria.  相似文献   

8.
Abstract

A field experiment was conducted on sodic soil during its rainy seasons of 2004 and 2005 to evaluate five germplasms of Ocimum basilicum (viz. CSLT 5, CSLT 9, CSLT‐12, CSLT‐12‐1, and CSLT‐13) for their growth performance, their oil yield, chemical constituents of their oil, and ion‐partitioning characteristics in different parts of the plants. The highest shoot yield was recorded in CSLT‐12, followed by CSLT‐9 and CSLT‐13. The highest oil yield was recorded in CSLT‐13, followed by CSLT‐12‐1. This indicated that a high herbage yield does not always result in a high oil yield. Germplasm CSLT‐12 and CSLT‐12‐1 seemed to have better adaptation in sodic soil then other germplasms on the basis of root architecture and root density. Germplasm CSLT‐5 was of the linalool chemotype, yielding 62.36% linalool in oil, whereas CSLT‐13 and CSLT‐9 were methyl chavicol chemotypes, yielding 69.59% and 56.98% of methyl chavicol, respectively. Germplasms CSLT 12 and CSLT 12‐1 are intermediate types that yielded 48.86% of methyl chavicol and 43.37% of linalool. The root, stem (main branch), and laterals (primary branches) were better sodium (Na)+accumulators then leaves and inflorescences. On the other hand, leaves were better chloride (Cl?) accumulators than roots. A higher K+/Na+ ratio was found in the immature leaves than in the matured leaves.  相似文献   

9.
The effects of essential oil treatment on fruit decay and antioxidant capacities in Chinese bayberries were evaluated. Chinese bayberries were treated with essential oils, including carvacrol, cinnamaldehyde, perillaldehyde, and linalool. Results from this study indicated that all essential oils significantly reduced fruit decay of Chinese bayberries, and the most effective compound was carvacrol. Treatment with carvacrol, cinnamaldehyde, perillaldehyde, and linalool significantly increased total phenolic, anthocyanin, and individual flavonoid contents. In addition, all essential oils maintained significantly higher antioxidant capacities as measured by scavenging capacity against superoxide, hydroxyl, and 1,1-diphenyl-2-picrylhydrazyl radicals and by the reducing power test compared to the control. Moreover, the activities of antioxidant enzymes were also enhanced by all essential oils. Thus, postharvest essential oil treatment has positive effects on reducing decay and enhancing antioxidant capacities in Chinese bayberries.  相似文献   

10.
Differences in timing of intensity perception of the retronasal aroma of a nonpolar (linalool) vs polar (diacetyl) compound when the matrix (milk) fat content was varied (0%, 1%, 5%, or 10% rapeseed oil) were studied using a time-intensity method. Aromas were also evaluated by orthonasal means and with static headspace gas chromatography (GC). With increasing fat content, linalool was considerably retained in the matrix, while the release of diacetyl was not affected. As little as 1% fat was sufficient to significantly reduce the volatility (GC results) of linalool and orthonasal, but not retronasal, intensity. No effect of fat was found on the rate of linalool release. The linalool perception of the sample containing the greatest amount of fat lasted a shorter time than that of the samples containing less fat; however, the decrease in intensity perception was steeper in lower fat samples. The observed temporal release of linalool partly challenges the often-repeated statement that reduction of fat results in a more rapid and shorter aroma release.  相似文献   

11.
Crushing intensity and distillation time were evaluated for their effects on the oil yield and composition of steam-distilled essential oil from fruits of Coriandrum sativum var. microcarpum L. A comparison of oils produced by laboratory- and pilot-scale stills showed that the two still types gave comparable yields and oil composition. The laboratory still was then used to compare oil yields and compositions from fruits crushed at three different intensities, at intervals during a distillation period of 60 min. Both crushing intensity and distillation time had significant (P< 0.05) effects on the yield and composition of the oil. The maximum oil yield was less from the light-crushed fruits, but the rate of oil recovery was significantly P < 0.05) higher. From the light-crushed fruits, 95% of the maximum yield was extracted in 22.5 min compared with 32 and 39 min for the standard and heavy-crushed fruits, respectively. The effect of crushing intensity on oil composition was most pronounced on the low-boiling-point a-pinene and on the higher-boiling-point geranyl acetate. Crushing had little effect on linalool content, but distillation time could be manipulated to alter the linalool content of the oil.  相似文献   

12.
Wild Amazonian basil Ocimum micranthum Willd. (O. campechianum Mill.) Labiatae essential oil was analyzed by GC and GC-MS: 31 compounds were identified. The main components were eugenol (46.55 +/- 5.11%), beta-caryophyllene (11.94 +/- 1.31%), and beta-elemene (9.06 +/- 0.99%), while a small amount of linalool (1.49 +/- 0.16%) was detected. The oil was tested for its in vitro food-related biological activities and compared with common basil Ocimum basilicum and Thymus vulgaris commercial essential oils. Radical scavenging activity was evaluated employing 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. The oil exerted a good capacity to act as a nonspecific donor of hydrogen atoms or electrons when checked in the diphenylpicrylhydrazyl assay, quenching 76,61 +/- 0.33% of the radical, with values higher than those reported by reference oils. In the beta-carotene bleaching test, the oil provided an antioxidant efficacy comparable with that of O. basilicum and T. vulgaris essential oils. These data were confirmed by photochemiluminescence, where the oil showed a remarkable antioxidant capacity (2.39 +/- 0.1), comparable to that of Trolox and vitamin E, and higher than the other essential oils. Antibacterial activity of O. micranthum essential oil was evaluated against Gram positive and Gram negative bacterial strains. The oil showed a dose-dependent antifungal activity against pathogenic and food spoiling yeasts.  相似文献   

13.
The content of phytosterol oxidation products was determined in samples of crude vegetable oils: peanut, sunflower, maize, palm nut, and lampante olive oils that were intended for refining and not for direct consumption. The 7 alpha- and 7 beta-hydroxy derivatives of beta-sitosterol, stigmasterol, and campesterol and the 7-keto-beta-sitosterol were the principal phytosterol oxides found in almost all of the oils analyzed. In some oils, the epoxy and dihydroxy derivatives of beta-sitosterol were also found at very low levels. The highest total concentrations of phytosterol oxides, ranging from 4.5 to 67.5 and from 4.1 to 60.1 ppm, were found in sunflower and maize oils, respectively. Lower concentrations were present in the peanut oils, 2.7-9.6 ppm, and in the palm nut oil, 5.5 ppm, whereas in the lampante olive oils, only three samples of the six analyzed contained a low concentration (1.5-2.5 ppm) of oxyphytosterols. No detectable levels of phytosterol oxides were found in the samples of palm and coconut oils. Bleaching experiments were carried out on a sample of sunflower oil at 80 degrees C for 1 h with 1 and 2% of both acidic and neutral earths. The bleaching caused a reduction of the hydroxyphytosterol with partial formation of steroidal hydrocarbons with three double bonds in the ring system at the 2-, 4-, and 6-positions (steratrienes). The same sunflower oil was deodorized at 180 degrees C under vacuum for 1 h, and no dehydration products were formed with a complete recovery of the hydroxyphytosterols. A bleaching test with acidic earths was carried out also with an extra virgin olive oil fortified with 7-keto-cholesterol, dihydroxycholesterol, and alpha-epoxy-cholesterol. There was no formation of steratrienes from these compounds, but dihydroxycholesterol underwent considerable decomposition and alpha-epoxycholesterol underwent ring opening with formation of the dihydroxy derivative, whereas 7-ketocholesterol was rather stable  相似文献   

14.
The oxidative stability of selected tree nut oils was examined. The oils of almond, Brazil nut, hazelnut, pecan, pine nut, pistachio, and walnut were extracted using two solvent extraction systems, namely, hexane and chloroform/methanol. The chloroform/methanol system afforded a higher oil yield for each tree nut type examined (pine nut had the highest oil content, whereas almond had the lowest). The fatty acid compositions of tree nut oils were analyzed using gas chromatography, showing that oleic acid was the predominant fatty acid in all samples except pine nut and walnut oils, which contained high amounts of linoleic acid. The tocopherol compositions were analyzed using high-performance liquid chromatography, showing that alpha- and gamma-tocopherols were the predominant tocopherol homologues present; however delta- and beta-tocopherols were also detected in some samples. The oxidative stability of nonstripped and stripped tree nut oils was examined under two conditions, namely, accelerated autoxidation and photooxidation. Progression of oxidation was monitored using tests for conjugated dienes, peroxide value, p-anisidine value, and headspace volatiles. Primary products of oxidation persisted in the earlier stages of oxidation, whereas secondary oxidation product levels increased dramatically during the later stages of oxidation. Hexanal was the major headspace aldehyde formed in all oxidized samples except walnut oil, which contained primarily propanal. Results showed that chloroform/methanol-extracted oils were more stable than hexane-extracted oils in both the accelerated autoxidation and photooxidation studies. Oils of pecan and pistachio were the most stable, whereas oils of pine nut and walnut were the least stable.  相似文献   

15.
Cinnamomum osmophloeum ct. linalool is one of the chemotypes of the indigenous cinnamon in Taiwan. In this study, hydrodistillation was used for extracting the essential oils (EOs) of C. osmophloeum ct. linalool leaves collected from various plants and seasons, and GC-MS and GC-FID were used to examine variations and contents of the chemical composition in EOs. Moreover, the absolute configuration of the main constituent and its EO content were illustrated by GC-FID with a chiral column. In addition, we also investigated the effect of the extraction time (1, 2, 6, and 10 h) on the yield of EO and the contents of the main constituents. Results from this study revealed that the average EO yield of 12 plants was 3.7%, and linalool accounted for more than 90%. The linalool in the EO was proved to be pure S-(+)-linalool, and its content in the leaves ranged from 28.8 ± 0.3 to 35.1 ± 0.2 mg/g. Furthermore, there were no obvious differences in EO yield and S-(+)-linalool content from various plants and seasons. On the other hand, we also demonstrated that EO and S-(+)-linalool from C. osmophloeum ct. linalool leaves can be completely extracted out by 1 h of hydrodistillation.  相似文献   

16.
Grain amaranth has been suggested as an alternative to marine animals as a natural source of squalene. Oil contents, squalene contents, and fatty acid profiles were determined in 11 genotypes of four grain amaranth species. Although the oil contents of grain amaranth were low (from 5.1% in Amaranthus tricolor to 7.7% in Amaranthus cruentus) as compared to other oil-containing grains, high concentrations of squalene were found in total lipids, ranging from 3.6% in Amaranthus hypochondriacus to 6.1% in A. tricolor. The major fatty acids in Amaranthus oil consisted of palmitic acid (19.1-23.4%), oleic acid (18.7-38.9%), and linoleic acid (36.7-55.9%). A high degree of unsaturation was observed in Amaranthus oils, with S/U ratios of 0.26-0.32. A method to isolate and purify the squalene from Amaranthus oil was developed. After the saponification of K112, the squalene content increased from 4.2% in the crude oil to 43.3% in the unsaponifiables by the removal of the saponifiables. The unsaponifiables were fractionated by silica gel column chromatography to get highly purified squalene. The squalene purity in certain fractions was as high as 98%. Combining the fractions rich in squalene gave a 94% squalene concentrate, with a yield of 90%. The structure of squalene in the purified sample was confirmed by comparison of its ultraviolet spectrum with a standard and from its nuclear magnetic resonance spectra.  相似文献   

17.
Volatile components of peel and leaf oils of lemon and lime species   总被引：1，自引：0，他引：1  
Peel and leaf oils of 43 taxa of lemons and limes were obtained from fruits and leaves collected from trees submitted to the same pedoclimatic and cultural conditions. Their chemical composition was investigated by capillary GC, GC-MS, and (13)C NMR, and the results were submitted to principal component analysis to check for chemical variability. Three major chemotypes were distinguished for lemon peel oils: limonene; limonene/beta-pinene/gamma-terpinene; and limonene/linalyl acetate/linalool. Two chemotypes were identified for lemon leaf oils: limonene/beta-pinene/geranial/neral and linalool/linalyl acetate/alpha-terpineol. In lime peel oils, four chemotypes were distinguished: limonene; limonene/gamma-terpinene; limonene/beta-pinene/gamma-terpinene; and limonene/gamma-terpinene/beta-pinene/oxygenated products. Four others were identified for lime leaf oils: beta-pinene/limonene; limonene/geranial/neral; limonene/linalool/citronellal; and limonene/sabinene/citronellal/linalool. These results were interpreted using principal component analysis.  相似文献   

18.
The qualitative and quantitative composition of the essential oil from black, green, and white pepper was determined by using a simultaneous distillation and extraction micromethod for oil isolation and gas chromatography (GC)/flame ionization detection (FID) and GC/mass spectrometry (MS) analysis techniques. The most abundant compounds in pepper oils were (E)-beta-caryophyllene (1.4-70.4%), limonene (2.9-38.4%), beta-pinene (0.7-25.6%), Delta-3-carene (1.7-19.0%), sabinene (0-12.2%), alpha-pinene (0.3-10.4%), eugenol (0.1-41.0%), terpinen-4-ol (0-13.2%), hedycaryol (0-9.1%), beta-eudesmol (0-9.7%), and caryophyllene oxide (0.1-7.2%). Green pepper corn obtained by a sublimation drying method gave more oil (12.1 mg/g) and a much higher content of monoterpenes (84.2%) in the oil than air-dried green pepper corn (0.8 mg/g and 26.8%, respectively). The oil from ground black pepper contained more monoterpenes and less sesquiterprnes and oxygenated terpenoids as compared to green and white pepper oils. After 1 year of storage of pepper samples in a glass vessel at room temperature, the amount of the oils isolated decreased, the content of terpenes decreased, and the amount of oxygenated terpenoids increased. Differently from other pepper samples, 1 year storage of green pepper corn raised the oil amount more than twice of both drying methods.  相似文献   

19.
The volatile components of Hyuganatsu (Citrus tamurana Hort. ex Tanaka) peel oil, isolated by cold-pressing, were investigated by chemical and sensory analyses. According to chemical analysis by GC and GC-MS, limonene (84.0%) was the most abundant compound, followed by gamma-terpinene (6.9%), myrcene (2.2%), alpha-pinene (1.2%), and linalool (1.0%). Monoterpene hydrocarbons were predominant in Hyuganatsu peel oil. The odor-active volatiles in Hyuganatsu flavor were studied by GC-olfactometry and omission tests. The characteristic flavor was present in the oxygenated fraction. Flavor dilution (FD) factors of the volatile flavor components of the Hyuganatsu cold-pressed oil were determined by aroma extraction dilution analysis (AEDA). Furthermore, relative flavor activity was investigated by means of FD factor and weight percent. Ten kinds of odor compounds having Hyuganatsu-like aroma were detected by AEDA: limonene, linalool, octanol, neral, neryl acetate, tridecanal, trans-carveol, cis-nerolidol, trans,trans-farnesyl acetate, and trans,trans-farnesol. Linalool and octanol were regarded as the most odor-active or key compounds of Hyuganatsu aroma. Diluted solutions of linalool and octanol of approximately 2 ppm gave a fresh and fruity aroma note similar to Hyuganatsu flavor.  相似文献   

20.
The hexane-extracted oil content of Moringa oleifera seeds ranged from 38.00 to 42.00%. Protein, fiber, and ash contents were found to be 26.50-32.00, 5.80-9.29, and, 5.60-7.50%, respectively. Results of physical and chemical parameters of the extracted oil were as follows: iodine value, 68.00-71.80; refractive index (40 degrees C), 1.4590-1.4625; density (24 degrees C), 0.9036-0.9080 mg/mL; saponification value, 180.60-190.50; unsaponifiable matter, 0.70-1.10%; and color (1 in. cell), 0.95-1.10 R + 20.00-35.30 Y. Tocopherols (alpha, gamma, and delta) in the oil were up to 123.50-161.30, 84.07-104.00, and 41.00-56.00 mg/kg, respectively. The oil was found to contain high levels of oleic acid (up to 78.59%) followed by palmitic, stearic, behenic, and arachidic acid up to levels of 7.00, 7.50, 5.99, and 4.21%, respectively. The induction period (Rancimat, 20 L/h, 120 degrees C) of the crude oil was 9.99 h and reduced to 8.63 h after degumming. Specific extinctions at 232 and 270 nm were 1.70 and 0.31, respectively. Many parameters of M. oleifera oil indigenous to Pakistan were comparable to those of typical Moringa seed oils reported in the literature. The results of the present analytical study were also compared with those of different vegetable oils.  相似文献   

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