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1.
The phenylpyrazole insecticide, fipronil, is used in seed coating against Agriotes larvae, which infest mainly corn and sunflower. Coating the seeds of the cultivated plants with fipronil has proven its effectiveness against Agriotes populations. In the case of sunflower or even corn, the possible root uptake of this insecticide may lead to a toxic effect against pollinators such as honeybees. In the present report, the uptake and transport of fipronil inside the sunflower seedling was studied in the laboratory. In a first study, sunflower was cultivated on an aqueous medium containing fipronil. An intense root uptake of fipronil occurred, leading to a transport into leaves depending upon transpiration. In a second study, plants were cultivated on a soil in which fipronil was uniformly distributed. Under our soil conditions (20% organic carbon), the partition coefficient between soil and water (K(d)) was found to be equal to 386 +/- 30. The average rate of fipronil transfer from soil water to seedlings was from 2 to 2.6 times lower than water transfer. During the 3 week experiment, 55% of recovered labeled compounds was in the parent form and 35% had been converted to lipophilic metabolites, with either a 4-CF(3)-SO(2) or 4-CF(3)-S substituant, which are also very potent lipophilic insecticides. This paper suggests that the possible uptake of fipronil by sunflower seedlings under agronomic conditions is mainly controlled by the physicochemical characteristics of the seed-coating mixture.  相似文献   

2.
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   

3.
Sesame lignans are working as antioxidants in various physiological functions. In the present study, the antioxidative effect of sesame lignans is examined in chemically induced diabetes mellitus (DM) in rats against lipid profile and lipid peroxidations. DM was induced in four groups of rats by injection of alloxan. The control groups (non-diabetic and diabetic) received a diet containing sunflower oil while the rest of the three experimental diabetic groups received a diet containing 0.25% alpha-tocopherol (D-Toc), 0.5% sesame lignan (D-SL), and 0.25% alpha-tocopherol+0.25% sesame lignan (D-Toc-SL) in sunflower oil for 4 weeks. Lipid profile and lipid peroxidations of plasma, erythrocyte membrane (EM), and liver tissues were measured. The total cholesterol, non-HDL cholesterol, plasma lipid peroxidation, and also LDL-peroxidation decreased, and HDL cholesterol increased significantly (P<0.05) in all the experimental groups as compared to the control diabetic sunflower oil group. The triacylglycerol (TAG) level in plasma decreased significantly in the D-SL and D-Toc-SL groups as compared to control diabetic group. Significant decrease in TAG level was observed in the D-SL group as compared to the D-Toc group. LDL peroxidation also decreased significantly in the D-Toc-SL group as compared to the D-Toc group. EM lipid peroxidation and liver lipid peroxidation decreased significantly in the D-Toc, D-SL, and D-Toc-SL groups as compared to the control diabetic group. Liver TAG level decreased more significantly in the D-SL and D-Toc-SL groups than in the control diabetic group. So, sesame lignans at 0.5% level and sesame lignan + alpha-tocopherol significantly ameliorate the alteration in lipid profile and the adverse free radical generative influence of DM induced by alloxan.  相似文献   

4.
In the present study, chemical constituents of the essential oil and oleoresin of the seed from Carum nigrum obtained by hydrodistillation and Soxhlet extraction using acetone, respectively, have been studied by GC and GC-MS techniques. The major component was dillapiole (29.9%) followed by germacrene B (21.4%), beta-caryophyllene (7.8%), beta-selinene (7.1%), and nothoapiole (5.8%) along with many other components in minor amounts. Seventeen components were identified in the oleoresin (Table 2) with dillapiole as a major component (30.7%). It also contains thymol (19.1%), nothoapiole (15.2.3%), and gamma-elemene (8.0%). The antioxidant activity of both the essential oil and oleoresin was evaluated in mustard oil by monitoring peroxide, thiobarbituric acid, and total carbonyl and p-anisidine values of the oil substrate. The results showed that both the essential oil and oleoresin were able to reduce the oxidation rate of the mustard oil in the accelerated condition at 60 degrees C in comparison with synthetic antioxidants such as butylated hydroxyanisole and butylated hydroxytoluene at 0.02%. In addition, individual antioxidant assays such as linoleic acid assay, DPPH scavenging activity, reducing power, hydroxyl radical scavenging, and chelating effects have been used. The C. nigrum seed essential oil exhibited complete inhibition against Bacillus cereus and Pseudomonas aeruginosa at 2000 and 3000 ppm, respectively, by agar well diffusion method. Antifungal activity was determined against a panel of foodborne fungi such as Aspergillus niger, Penicillium purpurogenum, Penicillium madriti, Acrophialophora fusispora, Penicillium viridicatum, and Aspergillus flavus. The fruit essential oil showed 100% mycelial zone inhibition against P. purpurogenum and A. fusispora at 3000 ppm in the poison food method. Hence, both oil and oleoresin could be used as an additive in food and pharmaceutical preparations after screening.  相似文献   

5.
Essential oil of Haplopappus greenei A. Gray was obtained by hydrodistillation of aerial parts, which were subsequently analyzed by gas chromatography and gas chromatography-mass spectrometry. Major components were identified as carvacrol (8.7%), beta-pinene (7.6%), trans-pinocarveol (6.2%), and caryophyllene oxide (5.8%), respectively. In total, 104 components representing 84.9% of the investigated essential oil were characterized. Furthermore, the essential oil was evaluated for antimalarial, antimicrobial, and antifungal activities. However, only antifungal activity was observed against the strawberry anthracnose-causing fungal plant pathogens Colletotrichum acutatum, Colletotrichum fragariae, and Colletotrichum gloeosporioides using the direct overlay bioautography assay. Major essential oil components were also evaluated for antifungal activity; the carvacrol standard demonstrated nonselective activity against the three Colletotrichum species and the other compounds were inactive.  相似文献   

6.
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   

7.
The screening for bioactive principles from several Chinese medicinal herbs showed that the essential oil of Cymbopogon distans aerial parts possessed strong repellency against the booklouse, Liposcelis bostrychophila , and the red flour beetle, Tribolium castaneum . A total of 36 components of the essential oil were identified by GC and GC-MS. trans-Geraniol (16.54%), (R)-citronellal (15.44%), (+)-citronellol (11.51%), and α-elemol (9.06%) were the main components of the essential oil followed by β-eudesmol (5.71%) and (+)-limonene (5.05%). From the essential oil, four monoterpenes were isolated by bioassay-guided fractionation. The compounds were identified as limonene, citronellol, citronellal, and trans-geraniol. Geraniol and citronellol were strongly repellent against the booklouse, L. bostrychophila, whereas citronellal and limonene exhibited weak repellency against the booklouse. Geraniol and citronellol exhibited comparable repellency against the booklouse relative to the positive control, DEET. Moreover, geraniol and citronellol exhibited stronger repellency against the red flour beetle than DEET, whereas the two other compounds showed the same level of repellency against the red flour beetle compared with DEET.  相似文献   

8.
Antilisterial activities of Thymbra capitata and Origanum vulgare essential oils were tested against 41 strains of Listeria monocytogenes. The oil of T. capitata was mainly constituted by one component, carvacrol (79%), whereas for O. vulgare three components constituted 70% of the oil, namely, thymol (33%), gamma-terpinene (26%), and p-cymene (11%). T. capitata essential oil had a significantly higher antilisterial activity in comparison to O. vulgare oil and chloramphenicol. No significant differences in L. monocytogenes susceptibilities to the essential oils tested were registered. The minimum inhibitory concentration values of T. capitata essential oil and of carvacrol were quite similar, ranging between 0.05 and 0.2 microL/mL. Antioxidant activity was also tested, the essential oil of T. capitata showing significantly higher antioxidant activity than that of O. vulgare. Use of T. capitata and O. vulgare essential oils can constitute a powerful tool in the control of L. monocytogenes in food and other industries.  相似文献   

9.
The essential oils from leaves and inflorescences of Hyptis martiusii Benth were analyzed by GC-MS. Twenty-six compounds representing 93.2% of the essential oil of leaves were characterized; Delta-3-carene (22.5%), 1,8-cineole (24.27%), beta-caryophyllene (6.15%), and bicyclogermacrene (6.32%) were found as the major components. In the essential oil of inflorescences 27 compounds representing 87.7% of the oil were identified. The major components were Delta-3-carene (13.5%), alpha-pinene (5.78%), beta-caryophyllene (6.59%), viridiflorene (8.25%), and germacrene B (5.21%). The essential oil of leaves and 1,8-cineole showed pronounced insecticidal effect against Aedes aegypti larvae and Bemisia argentifolii, the vectors of dengue fever and white fly fruit plague, respectively.  相似文献   

10.
Seeds of Matthiola incana contain oil rich (55-65%) in (n-3) linolenic acid. Selected lines were developed and evaluated for their agronomic and chemical parameters. Extracted oil was fed for 6 weeks to rats, which were compared with rats fed a diet containing coconut oil or sunflower oil. Cholesterol levels were significantly lowest in rats fed diets rich in M. incana oil (27% reduction), and triglycerides were significantly lower in rats receiving either M. incana or sunflower oil (36% reduction). The contents of arachidonic acid and other (n-6) fatty acids were significantly the lowest in the liver and plasma of rats that had received M. incana oil. The levels of (n-3) fatty acids were significantly greater in both the liver and plasma of rats fed M. incana oil. The ratio of (n-3)/(n-6) long-chain fatty acids in the plasma was 7 times higher in rats fed with M. incana oil than in those fed with sunflower oil and 6 times higher than in those fed coconut oil. The results demonstrate for the first time a beneficial effect of dietary M. incana oil in reducing cholesterol levels and increasing (n-3) fatty acid levels in the plasma. This new, terrestrial plant source of (n-3) fatty acids could replace marine oils and thereby contribute beneficially to the human diet.  相似文献   

11.
The effect of lipid composition and oxidation on dough bleaching has been determined. At >2.25% (flour basis), pure linoleic acid was very efficient in degrading β‐carotene in dough, unlike colza, corn, peanut, soy, or sunflower oil, which were mainly characterized by different polyunsaturated fatty acids content. In a very oxidized state, as determined by a peroxide index of >15 meq/kg of oil, sunflower oil (rich in polyunsaturated fatty acids) had a major bleaching activity on β‐carotene when compared with colza oil (less polyunsaturated), especially in combination with long mixing times. A combination of lipase (815 U), slightly oxidized oil (peroxide index of 2–5 meq/kg of oil), and linoleic acid (90 mg/100 g of flour) significantly degraded flour pigments (P < 0.05).  相似文献   

12.
The present study aimed to analyze the mycoflora and the occurrence of alternariol (AOH) and alternariol monomethyl ether (AME) in grain samples of sunflower during different stages of plant development in Nova Odessa, State of S?o Paulo, Brazil. The data obtained were correlated with the presence of fungi in soil, wind-dispersed fungi, and the predominant climatic conditions of the region where the experiment was carried out. Analysis of the mycoflora revealed the presence of Fusarium verticillioides and Alternaria alternata in 70% and 46% of the samples, respectively. The profile of wind-dispersed fungi also showed F. verticillioides as the most frequently isolated fungus (68%), although A. alternata was detected in 28% of samples. In soil, Penicillium was the most frequent species (49.9%), followed by F. verticillioides (47.7%) and A. alternata (10.9%). Regarding water activity, sunflower grains presenting a high frequency of isolation of F. verticillioides and A. alternatahad a water activity ranging from 0.92 to 0.96, and statistical analysis revealed a negative linear correlation between the isolation of fungi and water activity. HPLC analysis showed that 18% of the sunflower grains were contaminated with alternariol (24.9-170.9 ng/g) and 10% with alternariol monomethyl ether (14.1-108.6 ng/g). The contamination of sunflower grains with AOH and AME in the field was low when compared to the LD50 necessary to cause toxicity to animals. However, the contamination with other toxigenic fungi such as F. verticillioides may indicate the presence of other mycotoxins in sunflower grains and a possible synergistic effect between them. This is the first report of the natural occurrence of alternariol and alternariol monomethyl ether in sunflower grains in Brazil.  相似文献   

13.
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   

14.
利用盆栽试验,研究了丛枝菌根真菌(Glomus.caledonium)在不同程度铜污染土壤上对玉米苗期生长的影响。结果表明,即使在土壤施铜量达150mg/kg时,菌根真菌对玉米仍有近55%的侵染率;接种菌根真菌,能显著促进玉米根系的生长。菌根玉米的根系生物量和根系长度,平均较未接种处理分别提高108.4%和58.8%;接种处理的植株地上部生物量达到每盆(3株)10.58g,显著高于不施铜的非菌根玉米。这些结果表明,丛枝菌根真菌对铜污染具有较好的抗性;并且由于菌根的形成,使宿主植物明显地改善了对磷的吸收和运输,并能通过抑制土壤酸化、降低土壤可溶态铜的浓度等机制,增强宿主植物对铜污染的抗(耐)性。在150mg/kg施铜水平时,与非菌根玉米相比,菌根玉米地上部和根系铜浓度分别降低24.3%和24.1%,吸铜量分别提高了28.2%和60.0%,表明菌根植物对铜污染土壤具有一定的生物修复作用。  相似文献   

15.
The present study was designated to evaluate the antimicrobial and antioxidant activities of the essential oil, obtained by using a Clevenger distillation apparatus, water soluble (polar) and water insoluble (nonpolar) subfractions of the methanol extracts from aerial parts of Satureja hortensis L. plants, and methanol extract from calli established from the seeds using Gamborg's B5 basal media supplemented with indole-3-butyric acid (1.0 ppm), 6-benzylaminopurine (N(6)-benzyladenine) (1.0 ppm), and sucrose (2.5%). The antimicrobial test results showed that the essential oil of S. hortensis had great potential antimicrobial activities against all 23 bacteria and 15 fungi and yeast species tested. In contrast, the methanol extract from callus cultures and water soluble subfraction of the methanol extract did not show antimicrobial activities, but the nonpolar subfraction had antibacterial activity against only five out of 23 bacterial species, which were Bacillus subtilis, Enterococcus fecalis, Pseudomonas aeruginosa, Salmonella enteritidis, and Streptococcus pyogenes. Antioxidant studies suggested that the polar subfractions of the methanol extract of intact plant and methanol extract of callus cultures were able to reduce the stable free radical 2,2-diphenyl-1-picrylhydrazyl to the yellow-colored diphenylpicrylhydrazine. In this assay, the strongest effect was observed for the tissue culture extract, with an IC(50) value of 23.76 +/- 0.80 microgram/mL, which could be compared with the synthetic antioxidant agent butylated hydroxytoluene. On the other hand, linoleic acid oxidation was 95% inhibited in the presence of the essential oil while the inhibition was 90% with the chloroform subfraction of the intact plant. The chemical composition of a hydrodistilled essential oil of S. hortensis was analyzed by gas chromatography (GC)/flame ionization detection (FID) and a GC-mass spectrometry system. A total 22 constituents representing 99.9% of the essential oil were identified by GC-FID analaysis. Thymol (29.0%), carvacrol (26.5%), gamma-terpinene (22.6%), and p-cymene (9.3%) were the main components.  相似文献   

16.
The chemical composition of the essential oil obtained by steam distillation of the floral calyces of Ocotea bofo Kunth (Lauraceae) was studied by means of GC, GC-MS, and 1H, 13C, and bidimensional NMR (COSY, HSQC, HMBC). Twenty-five constituents were identified, and estragole (48.7%), alpha-phellandrene (19.6%) and sabinene (10.4%) were found to be the major components. Antimicrobial activity against six aerobic bacteria and five yeasts and antioxidant activity performed by photochemiluminescence (PCL), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and beta-carotene bleaching assays are reported. The oil showed fair inhibiting properties against bacteria and a good inhibition against most yeasts. Its radical scavenging and chain-breaking antioxidant properties were comparable to or better than those provided by synthetic controls. Particular emphasis has been given to the use of NMR as a fast and reliable tool to discriminate O. bofo essential oil from other commercial anethole- and estragole-rich oils, namely, Illicium verum, Foeniculum vulgare, and Artemisia dracunculus.  相似文献   

17.
The amount and variety of polycyclic aromatic hydrocarbons (PAHs) in fumes during frying of chicken legs in edible oils were determined using a modified smoke collection device and a GC-MS technique. Chicken legs were fried in soybean oil, canola oil, or sunflower oil at 163 degrees C for 1-4 h. Results showed that most smoke (99%) was collected in the condensation apparatus, whereas the rest (1%) was adsorbed onto adsorption wool. A large proportion of PAHs in the smoke were detected in adsorption wool, whereas a small portion was found in the condensation apparatus. Canola oil generated the largest content (500.9 g for a frying time of 4 h) of smoke, followed by soybean oil, and sunflower oil. A similar trend was observed for PAH formation in fumes, with the exception that soybean oil produced a higher level than canola oil.  相似文献   

18.
Hydrodistillation of Decalepis hamiltonii roots yielded an essential oil (0.33% v/w) that contained 2-hydroxy-4-methoxybenzaldehyde (37.45%), 2-hydroxybenzaldehyde (31.01%), 4-O-methylresorcylaldehyde (9.12%), benzyl alcohol (3.16%), and alpha-atlantone (2.06%) as major constituents, with aromatic aldehydes constituting the main fraction of this root's essential oil. The oil was tested for its antimicrobial activity against foodborne pathogens responsible for food spoilage and human pathologies using standard antimicrobial assays. It exhibited strong antimicrobial activity against Bacillus cereus, Bacillus megaterium, Candida albicans, Escherichia coli, Micrococcus luteus, Micrococcus roseus, and Staphylococcus aureus at a concentration range of 1:0 with inhibitory activities of 27, 23, 16, 19, 22, 19, and 23 mm, respectively, which are comparable to those of the standards. The roots of D. hamiltonii, therefore, may be considered as an inexpensive source of an essential oil rich in antimicrobial compounds against foodborne pathogens.  相似文献   

19.
针对目前油葵机械化收获存在缺少专用机械设备、籽粒损失率和破损率均较高、收获设备工作性能不可靠等问题,该研究设计了油葵联合收获机拨禾板式割台装置并介绍其结构与工作原理,建立拨禾齿的运动模型,分析拨禾机构运动特性并获取拨禾齿端点的运动轨迹。通过对拨禾齿端点运动轨迹仿真,分析拨禾板转速、机具前进速度与拨禾板圆周数量之间的变化关系;利用MATLAB软件编写程序,仿真获取相邻两拨禾齿端点的运动轨迹曲线,解决拨禾齿运动参数不合理、籽粒碰撞损失较高的难题。割台性能试验结果表明,当割台倾斜角度25°、绞龙转速150r/min、拨禾板与导板距离170 mm时,油葵花盘损失率为2.04%。进一步通过田间油葵收获正交试验和参数优化,分析油葵收获机前进速度、拨禾板转速、茎秆留茬高度的不同组合对油葵籽粒损失率及破损率的影响,利用Design-Expert获取最优参数组合。结果表明,当油葵收获机前进速度1.2 m/s、拨禾板转速240 r/min、茎秆留茬高度570 mm时,油葵籽粒损失率与破损率分别为1.90%和0.65%。研究结果可为提高油葵联合收获机的作业性能、油葵收获机的结构设计和参数优化提供参考。  相似文献   

20.
Although poppy seed oil is an expensive article of trade, no literature about identification methods for adulteration with cheaper vegetable oils, like sunflower oil, has been published. This kind of adulteration is a challenge for routine analytical methods, such as the determination of fatty acid composition, because of almost similar fatty acid ratios. The detection of adulteration of poppy seed oils with sunflower oils at different levels (5-40%, w/w) by using SPME-GC-MS and MALDI-ToF-MS is the subject of our investigation. With the mentioned SPME-GC-MS method, it was possible to detect an admixture of sunflower oils in all relevant (5-40%) amounts by using alpha-pinene as a marker compound. Admixture of sunflower oil with high levels of triolein (high-oleic acid type) could be undoubtedly detected by MALDI-MS down to the 5-10% level. In contrast, adulteration of pure poppy seed oil by "standard" sunflower oils remained indistinguishable using this MALDI-MS.  相似文献   

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