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1.
The supercritical fluid extraction (SFE) of the aerial parts of Perovskia atriplicifolia Benth. was studied. The effect of different parameters such as pressure, temperature, modifier identity, and modifier volume on the SFE of the plant was investigated. The extracts were analyzed by GC and GC-MS and compared with the essential oil obtained from P. atriplicifolia Benth by steam distillation. The supercritical extracts and the steam-distilled products had very different compositions. The main constituents of the oil obtained by steam distillation were 1,8-cineole, limonene, camphor, beta-caryophyllene, alpha-pinene, camphene, and alpha-humulene. On the other hand, the major components of SFE extracts were 1,8-cineole, limonene, camphor, beta-caryophyllene, gamma-cadinene, alpha-pinene, and alpha-terpinyl acetate. The results showed that increasing the temperature from 35 to 65 degrees C (at a constant pressure of 100 atm) drastically reduced the number of extracted components. Also, the number of extracted constituents and the percent of main analytes increased when lower pressures were used. Using different modifiers (e.g., methanol, ethanol, dichloromethane, and hexane) for the extraction of the plant at low pressure (100 atm) and temperature (35 degrees C) showed that hexane was more selective than the other modifiers.  相似文献   

2.
The essential oil from the gum of Pistachio (Pistacia vera L. (Anacardiaceae)) grown in Turkey was obtained by the hydro-distillation method, and its chemical composition was analyzed by GC and GC-MS. Moreover, the antimicrobial activities of the oil against the growth of 13 bacteria and 3 pathogenic yeasts were evaluated using the agar-disk diffusion and minimum inhibitory concentration (MIC) methods. The results showed that the essential oil contained about 89.67% monoterpenes, 8.1% oxygenated monoterpenes and 1.2% diterpenes. alpha-Pinene (75.6%), beta-pinene (9.5%), trans-verbenol (3.0%), camphene (1.4%), trans-pinocarveol (about 1.20%), and limonene (1.0%) were the major components. The antimicrobial results showed that the oil inhibited nine bacteria and all the yeasts studied, and the activities were considerably dependent upon concentration and its bioactive compounds such as carvacrol, camphene, and limonene. Moreover, the essential oil of the gum was found to be more effective yeastcide than Nystatin, synthetic yeastcide. Furthermore, the antibacterial activities of the oil were lower than those of standard antibiotics, ampicillin sodium, and streptomycine sulfate under the conditions studied.  相似文献   

3.
The antioxidant activity of a commercial rectified clove leaf essential oil (Eugenia caryophyllus) and its main constituent eugenol was tested. This essential oil comprises in total 23 identified constituents, among them eugenol (76.8%), followed by beta-caryophyllene (17.4%), alpha-humulene (2.1%), and eugenyl acetate (1.2%) as the main components. The essential oil from clove demonstrated scavenging activity against the 2,2-diphenyl-1-picryl hydracyl (DPPH) radical at concentrations lower than the concentrations of eugenol, butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA). This essential oil also showed a significant inhibitory effect against hydroxyl radicals and acted as an iron chelator. With respect to the lipid peroxidation, the inhibitory activity of clove oil determined using a linoleic acid emulsion system indicated a higher antioxidant activity than the standard BHT.  相似文献   

4.
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   

5.
Chestnut (Castanea sativa) is an important basic food in rural diets and a major starch crop used in a similar way to potatoes. Chestnuts are a fundamental economic resource in the "chestnut regions" not only for the fruit but also for the chestnut wood. Chestnuts have become increasingly important with respect to human health, for example, as an alternative gluten-free flour source. Chestnuts are also a rich source of other beneficial compounds, but there have been few studies on the composition during processing. In this study, we analyzed the chemical composition of three Portuguese cultivars at different stages of industrial processing. The chestnut cultivars were Longal, Judia, and Martaínha. All three cultivars had high moisture contents but were low in ash, crude fat, and crude protein contents, with high starch and low fiber contents. The free amino acid contents, including various essential amino acids, varied depending on the cultivar. All three cultivars also had a significant content of polyphenolics with gallic acid; ellagic acid was predominant among hydrolyzable and condensed tannins. Many of these compounds are known to exert significant positive effects on human health. The one-way analysis of variance for fresh chestnut shows significant differences among the three cultivars for most of the studied parameters. The same statistical analysis applied to each one of the two cultivars (Judia and Longal) sampled for the four processing steps analyzed indicates a significant effect of this factor in practically all of the constituents. On the other hand, the two-way analysis of variance shows that, besides the residual, the processing step and the interaction cultivar x processing step were the factors that more contributed for the total variation observed in the constituents analyzed, while the contribution of cultivar was much less significant.  相似文献   

6.
A study was conducted to evaluate the effect of cut on biomass productivity, oil content, composition, and bioactivity of Ocimum basilicum L. (cvs. German and Mesten) and Ocimum sanctum L. (syn. O. tenuiflorum L.) (cv. Local) in Mississippi. Yields of basil herbage and essential oil were high and comparable to those reported in the literature. Essential oil content of O. basilicum cv. German varied from 0.40 to 0.75%, the oil content of cv. Mesten varied from 0.50 to 0.72%, and the oil content of cv. Local (of O. sanctum) ranged from 0.17 to 0.50% in air-dried basil. Herbage and essential oil yields of cvs. German and Mesten of O. basilicum increased with the second and then again with the third cut, whereas herbage and oil yields of cv. Local of O. sanctum increased with the third cut relative to the previous cuts. Overall, essential oil yields were 115, 123, and 51 kg/ha for the cvs. German, Mesten, and Local, respectively. The major oil constituents of cvs. German and Mesten (of O. basilicum) were (-)-linalool (30-40%) and eugenol (8-30%), whereas the major oil constituents of cv. Local (of O. sanctum) were eugenol (8-43%) and methylchavicol (15-27%). Essential oils from both species grown in Mississippi showed in vitro activity against Leishmania donovani (IC50 = 37.3-49.6 microg/mL), which was comparable to the activity of commercial oil (IC50 = 40-50 microg/mL). Minor basil oil constituents (+)-delta-cadinene, 3-carene, alpha-humulene, citral, and (-)- trans-caryophyllene had antileishmanial activity, whereas other constituents were ineffective. None of the oil was cytotoxic to mammalian cells.  相似文献   

7.
The composition of essential oils from twigs and needles of Balkan pine (Pinus peuce Gris.) grown in northern Greece was investigated. The compounds were identified by using GC-MS analysis. The twig oil was rich in alpha-pinene (7.38%), beta-pinene (12.46%), beta-phellandrene (26.93%), beta-caryophyllene (4.48%), and citronellol (12.48%), and the needle oil was rich in alpha-pinene (23.07%), camphene (5.52%), beta-pinene (22.00%), beta-phellandrene (6.78%), bornyl acetate (9.76%), beta-caryophyllene (3.05%), and citronellol (13.42%). The mean oil yield was 2.85% for twigs and 0. 57% for needles.  相似文献   

8.
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   

9.
Carrot root oil (SCO), obtained by supercritical fluid carbon dioxide (SC-CO2) extraction, was characterized and compared to a commercial carrot oil (MCO) and a virgin olive oil (VOO) (cv. Coratina). SCO showed much higher contents of carotenes, phenolics, waxes, phytosterols, and sesquiterpene and monoterpene volatiles. In SCO, the most prominent components present in the fully investigated analytical fractions (fatty acids, triglycerides, waxes, phytosterols, long-chain aliphatic alcohols, superior triterpene alcohols, and volatiles) were, respectively, linolenic acid, trilinolein, waxes C38, beta-sitosterol, campesterol and stigmasterol, 1-hexacosanol, 24-methylencycloartanol and cycloartenol, beta-caryophyllene, alpha-humulene, alpha-pinene, and sabinene. In VOO, the major constituents of the above analytical classes were, respectively, oleic acid, trilinolein, waxes C36, unsaturated volatile C6 aldehydes (trans-2-hexenal most markedly), and the same prominent sterols and superior alcohols found in SCO. In MCO, which also contained a proportion of unknown plant oil, several components showed magnitudes that were lower compared to SCO but higher with respect to VOO. The last had the aliphatic and triterpene alcohol concentration higher compared to that of both SCO and MCO. Several chemometric methods, applied to different analytical data sets, proved to be effective in grouping the three oil kinds.  相似文献   

10.
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   

11.
More than 50 compounds were identified in essential oils from stems and leaves of Salvia officinalis L. plants harvested in July, in Arouca, in northern Portugal. About 40 of those compounds were also present in flower essential oils, collected from the same plants. alpha-Thujone was the major compound, representing about 55, 30, and 18% of the essential oils from stems, leaves, and flowers, respectively. Significant percentage variations in the main compound classes of the essential oils from shoots sampled over the year were recorded at two different sites in northern Portugal. From December to April, oxygenated monoterpenes (MO) decreased from approximately 67-72% to values of 42-43% of the essential oils. During the same time interval, the percentage of monoterpene hydrocarbons (MH) rose from 8-11% to 17-22%. At both sites, sesquiterpene hydrocarbons (SH) rose from approximately 7% in February to 19-22% in April, decreasing thereafter to approximately 9% in July. Oxygenated sesquiterpenes (SO) increased from a minimum of approximately 5% in July to a maximum of 8-11% in February, decreasing thereafter. The compounds that mostly accounted for the essential oil composition variation were alpha-pinene, beta-pinene, and camphene, as MH; alpha-thujone and camphor, as MO; alpha-humulene and beta-caryophyllene, as SH; and viridiflorol, as SO.  相似文献   

12.
Olives (Olea europaea cv. Cobran?osa, Madural, and Verdeal Transmontana) used for oil production were stored, in plastic containers, at 5 +/- 2 degrees C (70% relative humidity) for three different periods before oil extraction: 0, 7, and 14 days (T(0), T(7), and T(14), respectively). In the crop year 1997/1998 this procedure was done only for cv. Cobran?osa and in 1998/1999 for the three cultivars. After storage, the oils were extracted from the fruits, and the acidity, peroxide value, coefficients of specific extinction at 232 and 270 nm, stability, color, p-anisidine value, fatty acids, and tocopherols compositions were determined. The results confirm that storage of fruits produces losses in the olive oil quality. Acidity and stability to oxidation indicate a progressive deterioration of oil quality as fruit is stored. The storage time affects the total tocopherols contents, namely, alpha-tocopherol, which clearly decreased during fruit storage. The oil quality of the Verdeal Transmontana cultivar deteriorated more rapidly than that of Cobran?osa and Madural cultivars. This study also shows that cv. Cobran?osa, the main cultivar in the region, is a good choice in terms of final olive oil quality.  相似文献   

13.
The essential oil composition and genetic variability of six commercial cultivars of thyme (Thymus vulgaris L.), a Mediterranean medicinal and aromatic plant, were analyzed by GC-MS and randomly amplified polymorphic DNA (RAPD), respectively. All evaluated cultivars belong to the thymol chemotype, with differences in the concentrations of thymol, gamma-terpinene, p-cymene, and other minor components. The comparison of the oil components concentration by multivariate analysis allowed separation of the cultivars into two groups. All of the cultivars exhibited characteristic RAPD patterns that allowed their identification. On the basis of the RAPD patterns, the cultivars could be divided into two clusters, which coincides with results obtained by oil GS-MS analysis, with a correlation coefficient of -0.779.  相似文献   

14.
This study was conducted to determine the composition of kumquat (Fortunella japonica Swingle) cold-pressed peel oil and to determine which volatile components are primarily responsible for the aroma of this oil. Eighty-two compounds were identified in the oil by GC and GC-MS. The major compounds were limonene (93.73%), myrcene (1.84%), and ethyl acetate (1.13%). Flavor dilution (FD) factors and relative flavor activities (RFA) of volatile constituents were evaluated by aroma extract dilution analysis with gas chromatography-olfactometry (GC-O). Camphene, terpinen-4-ol, citronellyl formate, and citronellyl acetate showed high FD factors (>/=5) and RFA (>20). Citronellyl formate and citronellyl acetate were regarded as the characteristic odor components of the kumquat peel oil from the results of FD factor, RFA, and GC-sniffing. Citronellyl acetate is considered to be the odor component most similar to kumquat by organoleptic evaluation with GC-O.  相似文献   

15.
The chemical composition of the essential oil of the Sardinian Rosmarinus officinalis L. obtained by hydro distillation and steam\hydro distillation was studied using GC-FID and MS. Samples were collected at different latitude and longitude of Sardinia (Italy). The yields ranged between 1.75 and 0.48% (v/w, volume/dry-weight). A total of 30 components were identified. The major compounds in the essential oil were alpha-pinene, borneol, (-) camphene, camphor, verbenone, and bornyl-acetate. Multivariate analysis carried out on chemical molecular markers, with the appraisal of chemical, pedological, and random amplified polymorphic DNA data, allows four different clusters to be distinguished. The antimicrobial and antifungal tests showed a weak activity of Sardinian rosemary. On the other hand, an inductive effect on fungal growth, especially toward Fusarium graminearum was observed.  相似文献   

16.
Abstract

Aluminum (Al) toxicity is one of the major factors limiting plant growth in acid soils. To determine the response of taro [Colocasia esculenta (L.) Schott] to Al‐toxicity, cultivars (cv.) Lehua maoli and Bun long were grown in hydroponic solution at six initial levels of Al (0, 110, 220, 440, 890, and 1330 uM Al). Increasing Al levels significantly depressed fresh and dry weights of taro leaf blades, petioles, and roots, as well as leaf areas and root lengths. No significant cultivar differences were found for plant dry weights. However, significant cultivar differences were found for expansion growth parameters, with cv. Lehua maoli exhibiting greater leaf fresh weights and root lengths in the presence of Al, compared to cv. Bun long. Apparently, differential response of taro cultivars to Al is related to the ability of the Al‐tolerant cultivar to maintain water uptake and cell expansion in the presence of Al. The initial solution Al level that resulted in the greatest separation of growth differences between taro cultivars in their response to Al was 890 μM Al.  相似文献   

17.
In order to reduce the damage caused by late-season drought stress of canola, a factorial split plot experiment was performed on the basis of the randomized complete blocks design with three replications in Karaj, Iran. The treatments were potassium sulfate in two levels, including application and non-application of potassium sulfate, irrigation at three levels including normal irrigation (control), restricted irrigation from the flowering and pod formation stage, as factorial were in main plots and winter canola cultivars including Opera, L72, KR1, GKH3705, GKH0224 were in subplots. The interaction effect of potassium sulfate?×?irrigation?×?cultivar on seed yield, stomatal resistance, oil yield, linoleic acid, linolenic acid and glucosinolate was significant at the 1% level. The promising line of L72 in normal irrigation and application of potassium sulfate and Opera cultivar under late-season drought stress and application of potassium sulfate had the highest seed yield, oil yield and fatty acids composition.  相似文献   

18.
This research characterized flour and raw starches isolated from red and white sweet potato cultivars. Their composition, determined by proximate analysis, is typical of sweet potato cultivars. These cultivars have high amylose content (32-34%) and exhibit a Ca-type X-ray diffraction pattern. Similar gelatinization characteristics were detected for both starches with onset temperature of 67 degrees C and enthalpy of 10.5-11.0 J/g. Starches of both red and white cultivars had well-correlated (r (2) = 0.982) and high solubilization and swelling temperatures, starting at 80 degrees C. Pasting properties of the white cultivar exhibit lower tendency for retrogradation. Water and oil absorption capacities were low for both red and white flours. When parboiled, both cultivars showed improved water absorption capacity and decreased least gelation concentration. It is concluded that the white cultivar should be preferred when low retrogradation tendency is required.  相似文献   

19.
Abstract

The effect of soil sodicity [exchangeable sodium percentage (ESP)] on the growth, yield, essential oil composition, and cation accumulation of two cultivars (Bourbon and Cimpawan) of geranium (Pelargonium graveolens) were studied in a pot experiment. Irrespective of soil sodicity, two cultivars of geranium differed significantly in their plant height and herb and oil yield. Plant height was not significantly affected with increases in soil ESP from 0.7 (control) to 20.0 and 7.0, respectively, for cultivars (cv) Bourbon and Cimpawan, but further increase in soil ESP decreased the plant height. The herb yield of cv Bourbon significantly increased with increasing soil ESP to 16.0, and the oil yield increased with increasing ESP to 7.0. Further increase in soil ESP decreased the yield. The increase in yield of cv Bourbon was 13.1 and 15.1% in the herb and 40.0 and 15.2% in the oil over the control (ESP 0.7) at soil ESP of 7.0 and 16.0, respectively. Decreases in yield were 3.5, 4.9, 53.3, and 59.3% in the herb yield and 3.8, 5.7, 53.3, and 80.0% in the oil over control (ESP 0.7) at soil ESP of 20.0, 24.0, 28.0, and 30.0, respectively. The herb and oil yield of cv Cimpawan significantly decreased with increase in soil ESP. The decease in yield was 17.7, 20.2, 40.7, 53.1, 70.7, and 72.6% in the herb and 4.0, 6.8, 30.9, 45.4, 83.2, and 84.0% in the oil over control (soil ESP 0.7) at the soil ESP 7.0, 16.0, 20.0, 24.0, 28.0, and 30.0, respectively. The concentration of isomenthone, linalool, citronellyl formate, and geranyl formate in the essential oil increased at low levels of soil ESP (between 16.0 to 24.0) but decreased at high soil ESP (>28). The concentration of l‐citronellol, nerol, and geraniol gradually increased with increase in soil ESP. The increase in the soil ESP enhanced the concentration of sodium (Na) and decreased that of potassium (K) in shoot and root tissues of geranium as compared to control. The concentration of Ca in shoot tissues of cv Bourbon significantly decreased with increase in soil ESP, but in the cv Cimpawan, the Ca concentration was not significantly affected with increase in soil ESP from 0.7 to 16.0, and thereafter the Ca concentration significantly decreased with further increase in soil ESP. The concentration of Na, K, and Ca were relatively higher in shoot than in root tissues. The K/Na and Ca/Na ratios in shoot tissues of both cultivars of geranium decreased with increase in soil ESP. The K/Na and Ca/Na ratios in shoot were not found to be related to the differences in sodicity tolerance of the cultivars of geranium tested in this experiment. The concentration of zinc (Zn) in shoot tissues decreased with increase in soil ESP. The cv Bourbon maintained a higher concentration of Zn in shoot tissues at high sodicity than that of cv Cimpawan. The results suggest that the geranium is slightly to moderately tolerant of soil sodicity stress.  相似文献   

20.
Aiming at learning the effects of soil conditions and cultivar on the bacterial diversity in the rhizosphere of soybean (Glycine max(L.) Merr.), bacterial communities associated with four soybean cultivars grown in two soils were revealed by terminal-restriction fragment length polymorphism (T-RFLP) combined with sequencing analysis of a 16S rDNA clone library. Lower bacteria diversity was found in soil A which has higher salinity and nutrient contents, while the highest bacterial diversity was found in the rhizosphere of cv. Jidou 12 in both soils. These results revealed that both the soil conditions and soybean cultivar affected the community composition of rhizosphere bacteria, but the effect of soil conditions was greater than that of soybean cultivar as demonstrated by the principal component analysis. It also revealed that the abundant rhizosphere bacteria may also the main symbiotic or non-symbiotic nodule endophytes.  相似文献   

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