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1.
The composition and antimicrobial activity of the essential oil of Tanacetum walteri were studied. Aerial flowering parts of plant were collected from North Khorasan Province of Iran and the essential oil was isolated by hydrodistillation and analysed by GC-FID and GC-MS. Antimicrobial activity of the essential oil was determined by disc diffusion and MIC and MBC determination. Thirty-five compounds were identified in the oil of T. walteri accounting for 94.4% of the total oil. Thymol (22.5%), 1,8-cineole (8.2%), umbellulone (6.9%), α-bisabolol (6.3%) and camphor (5.3%) were as the principal constituents. The highest antimicrobial activity of the essential oil was observed against Staphylococcus aureus, Enterococcus faecalis and Klebsiella pneumoniae with MIC value of 0.63 mg/mL. The inhibitory effect of the essential oil of T. walteri could be attributed mainly to the high levels of phenolic compound thymol and oxygenated terpenes in essential oil.  相似文献   

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3.
The mixing fraction of didodecyldimethylammonium bromide (DDAB) in dodecyltrimethylammonium bromide + DDAB to produce a lamellar liquid crystal (L α) abruptly decreases upon addition of a small amount of m-xylene, whereas the mixing fraction becomes constant at high m-xylene content. Similar results were obtained in saturated hydrocarbon systems. It is considered that oil molecules in the surfactant palisade layer increases the effective cross-sectional area per surfactant head group, as, whereas as is constant if the oil molecules are solubilized in the core of the liquid crystal. The volume fraction of penetrating oil in the total solubilized oil is defined as a penetration parameter, Pe, which is calculated from small-angle X-ray scattering data. Pe is high in the m-xylene system, whereas it is low in the n-decane system. Even in the same oil system, Pe decreases dramatically with increasing solubilization. Hence, most of the oil added penetrates into a palisade layer at an early stage of oil addition. This causes a change in the mixing fraction of surfactant in the L α phase. Thereafter the oil is solubilized in the core of the bilayer with further addition of oil. Received: 20 April 1998 Accepted: 16 July 1998  相似文献   

4.
In this study, biological properties of the essential oil isolated from seeds of Foeniculum vulgare (F. vulgare) were evaluated. GC-MS analysis revealed Trans-Anethole (80.63%), L-Fenchone (11.57%), Estragole (3.67%) and Limonene (2.68%) were the major compounds of the essential oil. Antibacterial activity of the essential oil against nine Gram-positive and Gram-negative strains was studied using disc diffusion and micro-well dilution assays. Essential oil exhibited the antibacterial activity against three Gram-negative strains of Pseudomonas aeruginosa, Escherichia coli, and Shigella dysenteriae. The preliminary study on toxicity of seed oil was performed using Brine Shrimp lethality test (BSLT). Results indicated the high toxicity effect of essential oil (LC50 = 10 μg/mL). In vitro anticancer activity of seed oil was investigated against human breast cancer (MDA-Mb) and cervical epithelioid carcinoma (Hela) cell lines by MTT assay. Results showed the seed oil behave as a very potent anticancer agent with IC50 of lower than 10 μg/mL in both cases.  相似文献   

5.
Experimental data have been compiled from the published literature for the logarithm of the gas-to-peanut oil partition coefficient, log K, and for the logarithm of the water-to-peanut oil partition coefficient, log P, for a series of 93 solutes having a wide range of solute polarities and hydrogen-bonding character. The two sets of partition coefficients were correlated with the Abraham solvation parameter model. The derived Abraham model correlations described the experimental log K and log P values within standard deviations of 0.13 and 0.14 log units, respectively. Principal component analysis was used to compare the solvent properties of peanut oil to four other natural oils (olive oil, soybean oil, triolein and oleyl alcohol). Peanut oil was found to be close to olive oil and soybean oil, and quite far away from triolein and oleyl alcohol.  相似文献   

6.
Adulteration of Camellia oleifera Abel. oil with other cheaper oil has been a long‐term problem in Taiwan because the price of Camellia oleifera Abel. oil is much higher than that of other edible oils due to its distinguished physiological properties. To develop an efficient method for determining the authenticity of Camellia oleifera Abel. oil is of great importance. In previous study (Appl. Spectrosc. 2003 , 57, 413), we showed that the Raman intensity ratio of ν16561439 was capable of reflecting precisely the degree of unsaturation in edible oils. Accordingly, we further present this Raman method to determine the authenticity of Camellia oleifera Abel. oil. It showed that the intensity ratio (Iν1656/ν1439) changed concomitantly with the magnitude of double bonds in the binary mixtures of Camellia oleifera Abel. oil blended with other edible oil. A linear relationship with a high correlation coefficient (R2 = 0.9938) between the Raman intensity ratio of ν16561439 and the percentage of Camellia oleifera Abel. oil was obtained, which could be used to determine the authenticity of Camellia oleifera Abel. oils collected from various markets. It shows that FT‐Raman spectroscopy provides a direct, simple, rapid, and non‐invasive method to probe the authenticity of Camellia oleifera Abel. oil.  相似文献   

7.
The antibacterial activity of essential oil and methanolic extract of Teucrium polium was determined against Pseudomonas aeruginosa, Pantoea agglomerans, Brenneria nigrifluens, Rhizobium radiobacter, Rhizobium vitis, Streptomyces scabies, Ralstonia solanacearum, Xanthomonas campestris and Pectobacterium cartovorum by disc diffusion method. Minimum inhibitory concentration and minimum bactericidal concentration were determined by using the serial dilution method. Chemical composition of essential oil and methanolic extract was determined by GC-MS and HPLC. α-Pinene (25.769%) and myrcene (12.507) were of the highest percentage in T. polium essential oil, and sinapic acid (15.553 mg/g) and eugenol (6.805 mg/g) were the major compounds in the methanolic extract. Our results indicate that both methanolic extract and essential oil did not show antibacterial activity against P. aeruginosa. Also the essential oil did not show antibacterial activity against P. cartovorum. In general, both methanolic extract and essential oil showed the same antibacterial activity against R. solanacearum, P. agglomerans, B. nigrifluens and S. scabies.  相似文献   

8.
The composition and the antinociceptive activity of the essential oil of Stevia serrata Cav. from a population located in the west highlands of Guatemala were evaluated. A yield of 0.2% (w/w) of essential oil was obtained by hydrodistillation of the dried aerial parts of the plant. The essential oil analysed by GC-FID and GC-MS showed a high content of sesquiterpenoids, with chamazulene (60.1%) as the major component and 91.5% of the essential oil composition was identified. To evaluate antinociceptive activity in mice, the essential oil of S. serrata Cav. was administered as gavage, using three different doses. In the formalin test, the animals were pre-treated with oral doses of the essential oil before the administration of formalin. Oral administration of S. serrata Cav. essential oil produced a marked antinociceptive activity. Therefore, the plant could be domesticated as a source of essential oil rich in chamazulene for developing medicinal products.  相似文献   

9.
In this paper, biodegradable polycaprolactone (PCL) was used as the raw material to prepare micro/nanofibrous polycaprolactone membrane (PCLM) through solution blow spinning (SBS) technology. The effects of spinning conditions (distance, gas pressure, and spinning solution concentration) on PCLM structures were investigated. The obtained membranes were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, water contact angle, and thermogravimetric analysis instrument. The oil adsorbency and reusability of PCLM were measured. The oil adsorption capacity of PCLM for motor oil, peanut oil, and diesel oil was 15.93, 14.81, and 12.86 g·g?1, respectively. After 10 times of reuse, the adsorption capacity for motor oil, peanut oil, and diesel oil could still remain at about 80% of the first cycle. The kinetic and thermodynamic studies showed that the adsorption conformed to the first‐order kinetic model and Freundlich model. Thermodynamic parameters for oil adsorption ΔGθ, ΔHθ, and ΔSθ indicated the oil adsorption of PCLM was a spontaneous and physisorption process.  相似文献   

10.
The essential oil obtained from Wedelia urticifolia growing in Hunan Province, China, was analyzed for the first time by capillary GC and GC-MS. A total of 67 constituents, representing 98.68% in essential oil were identified. The major constituents of the oil were: α-pinene (8.85%), limonene (6.38%), carvacrol (6.15%), caryophyllene (6.08%), spathulenol (5.49%), sabinene (5.36%), camphor (4.34%). Antimicrobial potential of oil against bacterial strains (Pseudomonas aeruginosa, Escherichia coli and Bacillus subtilis, and Staphylococcus aureus), yeast strains (Hansenula anomala and Saccharomy cescerevisiae) and molds (Aspergillus niger, Chaetomium globosum, Mucor racemosus, and Monascus anka) was determined by disc diffusion method and broth micro dilution method, respectively. The oil exhibited promising antimicrobial effect as a diameter of zones of inhibition (16.8–24.9 mm). Minimum inhibitory concentration values of oil were ranged 62.5–1000 μg/mL.  相似文献   

11.
Inclusion complex between the essential oil of Mentha x villosa Hudson and β-cyclodextrin, with a 1:9 mass/mass oil–β-cyclodextrin ratio was prepared by co-precipitation and kneading methods in a hydroethanolic medium. The GC/MS analysis showed a total volatile content of 99.5% in the Mentha x villosa oil. The characterization of the complex involved the analysis of the original essential oil, the surface and the total extracted oils. Among 28 detected compounds in the original essential oil, 13 are monoterpenes and 10 sesquiterpenes, furthermore, piperitenone-oxide is the major component (35.4%). 12 compounds were totally and 11 partially complexed, 3 have been adsorbed only on the surface of the β-CD and 2 have not been detected neither in the surface oil nor in the complexed oil. A 13.6% encapsulation efficiency was observed, while the total oil and volatiles retention was 15 and 77%, respectively. Non-parametric statistic analysis of the data showed that the profile of the volatiles were not significantly different comparing the original oil and the complexed oil (p>0.04). The results of thermogravimetry-mass spectrometry and XRD analysis have proven the inclusion complex formation between the essential oil and cyclodextrin.  相似文献   

12.
The chemical composition of the essential oil obtained from aerial parts of Nepeta graciliflora was analysed, for the first time, by GC–FID and GC–MS. A total of 27 compounds were identified, constituting over 91.44% of oil composition. The oil was strongly characterised by sesquiterpenes (86.72%), with β-sesquiphellandrene (28.75%), caryophyllene oxide (12.15%), α-bisabolol (8.97%), α-bergamotene (8.51%), β-bisabolene (6.33%) and β-Caryophyllene (5.34%) as the main constituents. The in vitro activity of the essential oil was determined against four micro-organisms in comparison with chloramphenicol by the agar well diffusion and broth dilution method. The oil exhibited good activity against all tested organisms.  相似文献   

13.
Melicope denhamii leaf volatile oil was isolated by hydrodistillation, and twenty-six constituents comprising 95.95% of the leaf oil were characterised by gas chromatographic techniques. Sesquiterpenes, zierone (22.49%) and α-gurjunene (19.96%), were identified as the major components. M. denhamii leaf oil tested against Gram-positive and Gram-negative bacteria showed significant activity against Bacillus subtilis and Escherichia coli. Anticancer activity of M. denhamii leaf oil against Dalton's lymphoma ascites cells was assessed by trypan blue exclusion and MTT assays, and the oil showed significant cytotoxicity at CD50 of 12.2 μg/mL. Induction of apoptosis on DLA cells by M. denhamii leaf oil was confirmed by morphological observation, nuclear damage and comet assays.  相似文献   

14.
Rationale: The illegal cooking oil has become a serious social problem and raised widespread alarm recently. However, an efficient and sensitive technique for identifying the potential illegal cooking oil is still unavailable, especially when mixed with the ordinary ones; there is an urgent need to develop an efficient method for identifying the illegal cooking oil. Sterols in the cooking oil could be used as an indicator to identify the source and quality of oil by detecting the kinds of phytosterols and zoosterols. However, those sterols are difficult to be ionized by electrospray ionization, which resulted in the low sensitivity in electrospray ionization (ESI)‐mass spectrometric (MS) analysis. Methods: N‐alkylpyridinium isotope quaternization was extended to charge label sterols in different cooking oil and attached N‐cationic pyridinium tag onto the sterols in the presence of trifluoromethanesulfonic anhydride (Tf2O); the kinds of sterols were identified and quantified by comparing d0/d5 pairs and product scan from ESI‐quadrupole‐time of flight (Q‐TOF) MS analysis. Results: The derivatized sterols were attached with permanent charge, resulting in the significant enhancement of ionization in ESI‐Q‐TOF MS analysis. The detection limits of analytes were improved to 0.02–0.05 ng/mL; different kinds of phytosterol, zoosterol and oxides were identified and quantified by comparing d0/d5 pairs from full scan and product scan. The method was applied in the detection of zoosterol for identifying the potential recycled cooking oil, even when the illegal oil has been blended into the ordinary one. More zoosterol was detected in the recycled oil compared with other cooking oil. Conclusions: The use of N‐alkylpyridinium isotope quaternization method provided an alternative method for identifying the potential illegal cooking oil. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
This study describes the qualitative and quantitative chemical composition and evaluates the antibacterial activity of essential oil from Eugenia platysema leaves. Analysis by GC–FID and GC–MS allowed the identification of 22 compounds. Different from the other species of the Eugenia genus, the major compound found in the essential oil was the diterpene phytol (66.05%), being this the first report of the presence of this compound in the essential oils from Eugenia genus. The sesquiterpene elixene was the second most concentrated compound in the studied essential oil (9.16%). The essential oil from E. platysema was tested for its antibacterial activity against cell-walled bacteria and mollicute strains of clinical interest using the microdilution broth assay. The results showed that the essential oil of E. platysema was inactive until 1000 μg mL?1 against tested bacteria.  相似文献   

16.
The composition of the essential oil obtained from the resin of Canarium album (Lour.) Raeusch, Burseraceae, growing in Vietnam, was studied by GC and GC/MS. Twenty-nine compounds representing 95.2% of the oil were identified. Monoterpenoids made up 93.2% of the oil, with β-pinene (33.3%), α-terpinene (19.4%), γ-terpinene (14.1%), and terpinen-4-ol (11.9%) as the main components. Sesquiterpenoids made up 2.0% of the oil, and the content of each individual was below 0.5% of the oil. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 421–422, September–October, 2006.  相似文献   

17.
In the present study analyses concerning the composition of vitamin E, sterols, triglycerides, and fatty acids of three Teucrium species (Teucrium alopecurus, T. nabli, and T. polium) seed oil were performed. Linoleic, linolenic, and palmitic were the major fatty acids. The oil was characterized by a high amount of phytosterol, wherein clerosterol, sitosterol, and stigmasterol are the main constituents. The amount of tocopherol is nearly 550 mg/kg of oil, with α-tocopherol as the major isomer. Information concerning the composition of Teucrium seed oil is very important for evaluating the therapeutic effect of this oil. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 261–264, May–June, 2009.  相似文献   

18.
The antibacterial effects of Thymus vulgaris (Lamiaceae), Lavandula angustifolia (Lamiaceae), and Calamintha nepeta (Lamiaceae) Savi subsp. nepeta var. subisodonda (Borb.) Hayek essential oils on five different bacteria were estimated. Laboratory control strain and clinical isolates from different pathogenic media were researched by broth microdilution method, with an emphasis on a chemical composition–antibacterial activity relationship. The main constituents of thyme oil were thymol (59.95%) and p-cymene (18.34%). Linalool acetate (38.23%) and β-linalool (35.01%) were main compounds in lavender oil. C. nepeta essential oil was characterized by a high percentage of piperitone oxide (59.07%) and limonene (9.05%). Essential oils have been found to have antimicrobial activity against all tested microorganisms. Classification and comparison of essential oils on the basis of their chemical composition and antibacterial activity were made by utilization of appropriate chemometric methods. The chemical principal component analysis (PCA) and hierachical cluster analysis (HCA) separated essential oils into two groups and two sub-groups. Thyme essential oil forms separate chemical HCA group and exhibits highest antibacterial activity, similar to tetracycline. Essential oils of lavender and C. nepeta in the same chemical HCA group were classified in different groups, within antibacterial PCA and HCA analyses. Lavender oil exhibits higher antibacterial ability in comparison with C. nepeta essential oil, probably based on the concept of synergistic activity of essential oil components.  相似文献   

19.
Spent engine oil, a mixture of aliphatic and aromatic compounds, is one of the frequent environmental pollutants. In this paper, biodesulfurization of spent oil using Rhodococcus sp. was studied. Batch studies were conducted varying the oil to aqueous medium ratio of 10:90 to 90:10. The results demonstrated that maximum desulfurization of 80% was obtained at the oil to aqueous phase ratio of 70:30. Kinetic parameters of Monod type growth model, namely, µmax, maximum specific growth rate and Ks, the half saturation constant were determined by varying the initial sulfur content of spent oil in the range of 0.16–1.05% (w/v). Gas chromatography–mass spectrometry was done to identify the compounds present in treated and untreated spent engine oil. The surface tension and emulsification indices of both oil and aqueous phases were also determined at different reaction times.  相似文献   

20.
New polymeric materials have been prepared by the cationic copolymerization of regular soybean oil, low saturation soybean oil, i.e. LoSatSoy oil, or conjugated LoSatSoy oil with styrene and divinylbenzene, norbornadiene or dicyclopentadiene initiated by boron trifluoride diethyl etherate (BF 3·OEt 2) or related modified initiators. The effects of the stoichiometry, the type of soybean oil and the alkene comonomer on the damping behavior of the resulting polymers have been investigated. The damping properties have been quantitatively evaluated by the loss tangent maximum (tan δ) max, ­the temperature range ΔT for efficient damping (tan δ > 0.3), and the integrals of the linear tan δ v. temperature curves (tan δ area, TA). These bulk materials are composed primarily of soybean oil‐styrene‐divinylbenzene random copolymers with considerable variability in the backbone compositions. The good damping properties of the soybean oil polymers are presumably determined by the presence of fatty acid ester side groups directly attached to the polymer backbone and the segmental heterogeneities resulting from crosslinking. In general, crosslinking reduces the (tan δ) max and the TA values, but broadens the region of efficient damping (ΔT). Soybean oil polymeric materials with appropriate compositions and crosslink densities are capable of efficiently damping over a temperature region in excess of 110 °C and provide noise and vibration attenuation over broad temperature and frequency ranges. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

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