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1.
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   

2.
The essential oil isolated from Turkish tarragon (Artemisia dracunculus) by hydrodistillation was analyzed by GC-MS. Thirty compounds representing 99.5% of total oil were identified. The predominant components in the oil were (Z)-anethole (81.0%), (Z)-beta-ocimene (6.5%), (E)-beta-ocimene (3.1%), limonene (3.1%), and methyleugenol (1.8%). The antibacterial and antifungal activities of the essential oils isolated from A. dracunculus, Artemisia absinthium, Artemisia santonicum, and Artemisia spicigera oils were also evaluated. In general, the oils exhibited potent antifungal activity at a wide spectrum on the growth of agricultural pathogenic fungi. Among the oils, the weakest antifungal activity was shown by the oil of A. dracunculus. In many cases, the oils of A. absinthium, A. santonicum, and A. spicigera completely inhibited the growth of some fungal species. As compared with antibacterial activities of all of tested oils, A. santonicum and A. spicigera oils showed antibacterial activities over a very wide spectrum. However, the essential oils tested showed lower inhibition zones than the inhibition zones of penicillin. In addition, antioxidant and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities of tarragon oil were determined, and weak antioxidant and DPPH radical scavenging activities were found in comparison to butylated hydroxytoluene.  相似文献   

3.
Huajiao denotes the fruits of various species of Zanthoxylum in the plant family Rutaceare used for cooking. The two most commercially popular species are bungeanum (red huajiao) and schinifolium (green huajiao). Fresh huajiao has a very high content of essential oil, up to 11%, which is described as having fresh, spicy, floral, cooling, and green aroma notes. A comprehensive analysis of the essential oils by GC-MS using advanced peak deconvolution and data processing software, revealed many overlapping components. A total of 120 aroma compounds for each species has been found. In the essential oils, linalyl acetate (15%), linalool (13%), and limonene (12%) are the major components of red huajiao, whereas linalool (29%), limonene (14%), and sabinene (13%) are the major components of green huajiao. For estimation of the aroma contribution of individual components, a new concept, "aroma character impact value" (ACI), is introduced as the percentage of the ratio of the concentration of an aroma component to its odor threshold value. Despite the differences in major components, both species have six common compounds of top aroma character impact: linalool, alpha-terpineol, myrcene, 1,8-cineole, limonene, and geraniol. The tingling sensation of huajiao is caused mainly by the alkylamide hydroxy-alpha-sanshool. The tingling compound decomposes easily under hydrolytic conditions or under UV light.  相似文献   

4.
The isolation and structure elucidation of antifungal constituents of the steam-distilled essential oil fraction of Artemisia dracunculus are described. Antifungal activities of 5-phenyl-1,3-pentadiyne and capillarin against Colletrotichum fragariae, Colletrotichum gloeosporioides, and Colletrotichum acutatum are reported for the first time. The relative abundance of 5-phenyl-1,3-pentadiyne is about 11% of the steam-distilled oil, as determined by GC-MS. Methyleugenol was also isolated and identified as an antifungal constituent of the oil.  相似文献   

5.
The potential of vibrational spectroscopy methods (attenuated total reflectance/Fourier-transform-infrared (ATR/FT-IR), FT-Raman and near infrared (NIR) spectroscopy) for the identification and quantification of valuable as well as carcinogenic substances in different basil chemotypes is described. It is shown that all main volatile components occurring in different basil accessions can be reliably determined in the isolated essential oils or solvent extracts but also in the air-dried herbs. While NIR data can be interpreted only by chemometric methods, IR and Raman spectra present characteristic key bands of the individual volatiles; therefore, in the latter case, a discrimination of basil chemotypes is frequently possible without applying chemometric algorithms. NIR calibrations are successfully established for various terpenoids and phenylpropanoids; on the basis of these data, the content of the two carcinogenic compounds methyleugenol (range: 2-235 microg/100 g) and estragole (range: 34-138 microg/100 g) can be reliably predicted in air-dried basil leaves (R (2) (coefficient of determination) = 0.951; SECV (standard error of cross validation) = 19.1 microg/100 g and R (2) = 0.890; SECV = 12.8 microg/100 g, respectively). The described methods were found to be very useful tools for the efficient selection of special basil single plants, adapted to the new demands set by the legislator and the consumer. Furthermore, they can be applied in industry to very easily control the purifying, blending, and redistilling processes of basil oil.  相似文献   

6.
The use of zinc oxide nanoparticles (nano-ZnO) has rapidly increased in recent years, and this has triggered the need for versatile toxicity tests that can be used to test a range of different exposure scenarios. Acute exposure studies, using a variety of plant species, have overwhelmingly demonstrated nano-ZnO-induced toxicity, but substantial differences in the degree of phytotoxicity are reported in different studies. Here, we analysed the role of exposure time in determining the variation in phytotoxic effects. Using the model species Lemna minor, the effects of short-term (24 h), standardised (1 week) and chronic (up to 6 weeks) nano-ZnO exposure were compared. Nano-ZnO effects on Lemna minor growth indicators (biomass growth rate, root length), chlorophyll content and photosynthetic efficiency were measured. Rapid inhibitory effects of nano-ZnO on the maximal quantum yield of photosystem II could be measured after just 24-h exposure. Standardised (1 week) experiments revealed phytotoxic effects on Lemna minor biomass growth. More severe inhibitory effects on growth developed gradually over 4 to 6 weeks exposure to nano-ZnO, and these were qualitatively associated with increased zinc content in the plant. Such dynamics of nano-ZnO toxicity have not been elucidated before, and this study emphasises the importance of exposure time in studies of nanoparticle toxicity. We conclude that short-term, standardised experiments can potentially underestimate the environmental phytotoxicity, which may result from chronic exposure to nano-ZnO.  相似文献   

7.
Volatile oil extracts of fennel seeds (Foeniculum vulgare Mill.) and thyme leaves (Thymus vulgaris L.) were obtained by simultaneous distillation-extraction (SDE) and supercritical fluid extraction (SFE) and analyzed by gas chromatography-mass spectrometry (GC-MS). In general, fennel oil extracted by SDE and SFE showed similar compositions, with trans-anethole, estragole, and fenchone as the main components. In contrast, thymol and p-cymene, the most abundant compounds in thyme leaves, showed big differences, with generally higher amounts of monoterpenes obtained by SDE. However, in this case, the differences between the extracts were higher. Key odorants of fennel seeds determined by gas chromatography-olfactometry (GC-O) showed similar patterns when applying SDE and SFE. trans-Anethole (anise, licorice), estragole (anise, licorice, sweet), fenchone (mint, camphor, warm), and 1-octen-3-ol (mushroom) were the most intense odor compounds detected in fennel extracts. Thymol and carvacrol, with oregano, thyme, and spicy notes, were identified as key compounds contributing to the aroma of thyme leaves.  相似文献   

8.
川滇黔接壤地区是中国滑坡灾害的多发区,区内共有崩塌、滑坡等地质灾害隐患点1.2万余处,对100余万人的生命与财产安全构成威胁,严重影响当地人民生产、生活安全与可持续发展。选择坡度、相对高差、到活动断裂带距离、年均降雨量和年均大雨日数5个因子作为滑坡危险性的评价因子,在GIS支持下获取各因子的贡献权重,根据贡献率模型在空间叠加下生成研究区滑坡危险性评价图。结果表明:(1)研究区1.92×105 km2面积中,极高危险区3.92×104 km2,高危险区4.34×104 km2,中危险区4.58×104 km2,低危险区3.92×104 km2,稳定区2.42×104 km2,中度以上危险区面积占研究区总面积的67.00%;(2)极高危险区主要分布在小江—安宁河深大断裂两侧以及金沙江、雅砻江等深切河谷中,显示出活动断裂带和地貌对滑坡危险性的宏观控制作用;(3)中度以上危险区内人口总量约1 152.31万人,占总人口的32.17%;GDP约419.88亿元,占研究区总量的28.75%,因此加强川滇黔接壤地区地质灾害防灾减灾能力建设已刻不容缓。  相似文献   

9.
A new chemical compound was tested for its insecticidal activity against several major insect pests. The compound, called "flufenerim", has a core pyrimidine structure and an unknown mode of action and showed potent activity against the sweet potato whitefly Bemisia tabaci (Gennadius), the green peach aphid Myzus persicae (Sulzer), and the African cotton leafworm Spodoptera littoralis (Boisduval); however, it did not show any activity against two thrips species: western flower thrips Frankliniella occidentalis (Pergande) and tobacco thrips Thrips tabaci (Lindeman). The compound was relatively potent against the three tested pests and caused mortality rates that reached up to 100% at concentrations under 10 mg of active ingredient (ai) L(-1). The action of the compound was very fast, and mortality was observed within 48 h after exposure of the insects to treated leaves. A unique characteristic of this compound is its very short residual activity, which approximates to 4 days after application under laboratory conditions and to 2 days under outdoor conditions for both B. tabaci and S. littoralis. Although this new compound's mode of action is yet unknown, its rapid and potent action against sap-sucking pests suggests that it acts on a very important target site in the insect body and possibly could be applied very close to harvesting.  相似文献   

10.
The compositions of essential oils isolated from the aerial parts of Artemisia absinthium, Artemisia santonicum, and Artemisia spicigera by hydrodistillation were analyzed by GC-MS, and a total of 204 components were identified. The major components of these essential oils were camphor (34.9-1.4%), 1,8-cineole (9.5-1.5%), chamazulene (17.8-nd%), nuciferol propionate (5.1-nd%), nuciferol butanoate (8.2-nd%), caryophyllene oxide (4.3-1.7%), borneol (5.1-0.6%), alpha-terpineol (4.1-1.6%), spathulenol (3.7-1.3%), cubenol (4.2-0.1%), beta-eudesmol (7.2-0.6%), and terpinen-4-ol (3.5-1.2%). The antifungal activities of these essential oils were tested against 11 plant fungi and were compared with that of a commercial antifungal reagent, benomyl. The results showed that all of the oils have potent inhibitory effects at very broad spectrum against all of the tested fungi. Pure camphor and 1,8-cineole, which are the major components of the oils, were also tested for antifungal activity against the same fungal species. Unlike essential oils, these pure compounds were able to show antifungal activity against only some of the fungal species. In addition, the antioxidant and DPPH radical scavenging activities of the essential oils, camphor, and 1,8-cineole were determined in vitro. All of the studied essential oils showed antioxidant activity, but camphor and 1,8-cineole did not.  相似文献   

11.
To clarify whether a particular group of soils of Archangelsk region (European N Russia) with humus‐rich topsoils exceeding the plowing zone supports an anthropogenic formation, four exemplary profiles were investigated. The investigation sites are characterized by distinct elevated surfaces, and the soils show thick toplayers of up to 60 cm with enrichment of soil organic matter and artifacts like brick, charcoal, and peat fragments, all indicating an anthropogenic origin. Increased phytolith amounts and high P contents of up to 800 mg kg–1 citric acid–soluble P and up to 1,400 mg kg–1 total P in the top horizons support an anthropogenic influence. These properties are very similar to the Plagganthrepts of NW Europe. The same is true regarding the main management aims: increasing soil fertility and overcoming the need of bedding materials. Having the required depths of the anthropogenic topsoil, the properties of the soils of the Archangelsk region allow a classification as Agrozems (Russian classification), Plaggenesche (German classification), and Plagganthrepts (US taxonomy). Since the high base saturation of the topsoil excludes a designation as plaggic horizon, the topsoil has to be considered as terric horizon, which leads to a classification as Terric Anthrosol according to WRB.  相似文献   

12.
This paper presents the results of physicochemical treatment on Pb-, Cu-, Sb-, and Zn-contaminated Canadian small arm firing range (SAFR) backstop soils in order to evaluate the potential of such methods for remediation of SAFR backstop soils. Remediation target for the treatment assays was to attain the Québec Department of Environment commercial C criterion or more realistically, to reach the soil burial D criterion. Two treatment lines (TL) were evaluated. TL-1, consisting of jig and Wilfley table (WT) treatments on the 0.5–3 mm and 53–500 μm soil size fractions (SF), respectively, and chemical leaching on the <53 μm SF and TL-2, consisting of jig on the 1–4 mm SF, spiral, and WT treatments on 250 μm–1 mm SF, and Kelsey jig assays on the <250 μm SF. For both TL, the untreated SF (>3 mm for TL-1; >4 mm for TL-2), and the gravimetric separation concentrates could be sent for recycling in smelter facilities. Results showed that the finer SF (<53 μm SF for TL-1; <250 μm SF for TL-2) were very difficult to treat. Even with metal removed mass proportions up to 78% for Pb, concentrations were still very high after chemical leaching; and the Kelsey jig showed deceiving metal removed mass proportions (up to 47% for Pb). In both TL, the jig and the WT showed Pb removed mass proportions up to 98% and treated mass proportions up to 77% in their respective SF. Whole process efficiencies in the cleaned soils showed that TL-1 led to the remediation of up to 65% of the initial total soil, and TL-2, 36%. TL-1 and TL-2 results showed that the WT effectively treated soils of 53 μm–1 mm SF, and the jig, soils of the 1–4 mm SF. Our study shows that gravimetric concentration techniques are very promising for the treatment of SAFR backstop soils, and further research has to be done in order to treat the SF lower than 53 μm.  相似文献   

13.
Gamma-linolenic acid is an essential fatty acid for humans with delta-6-desaturase deficiency; it is a precursor of prostaglandins, prostacyclins, and tromboxanes; and it has antiinflammatory and antitumoral effects. Tocopherols are natural antioxidants with biological activity, heart/vascular, and cancer protective properties. The oil, gamma-linolenic acid, and tocopherol contents, as well as tocopherol composition, were investigated in the seed oil of a collection of 47 accessions belonging to various species of the genus Ribes. Differences for oil content among species were not significant. The highest total tocopherol content was found in R. nigrum (mean, 1716 mg kg(-1) oil), followed by R. rubrum (mean, 1442 mg kg(-1) oil). R. grossularia showed the lowest values for this trait (mean, 786 mg kg(-1) oil). The three species also differed strongly for tocopherol composition. R. rubrumwas distinguished by a higher concentration of delta-tocopherol (mean, 20.2%); R. grossularia displayed the highest percentage of gamma-tocopherol (mean, 70.0%), and R. nigrum showed the highest concentration for alpha-tocopherol (mean, 34.8%), the most biologically active among the four tocopherols. Regarding gamma-linolenic acid, the highest content was found in R. nigrum, which exhibited up to 15.8% of this essential fatty acid in the oil. R. grossularia and R. rubrum showed mean gamma-linolenic acid contents of 8% and 6.2%, respectively. The present study indicated that seeds of Ribes species, especially R. nigrum, could be used as sources of gamma-linolenic acid and natural vitamin E.  相似文献   

14.
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15.
磷是作物和畜禽生长必需的营养元素,同时也是不可再生资源。为了提高农牧业生产力,80%左右的磷矿石用于生产磷肥与磷饲料添加剂,因此提高磷肥和磷饲料添加剂生产效率至关重要。然而关于磷肥和磷饲料添加剂"采矿—选矿—磷酸—磷肥/磷饲料添加剂"整个链条的磷流动特征和各个环节效率的定量研究却很少。本研究通过企业实地调研,建立企业流动数据库,利用物质流分析的方法扩展了NUFER(NUtrient flows in Food chains,Environment and Resources use)模型的磷肥和饲料磷添加剂生产模块。以我国某大型磷化工企业为例,定量揭示磷化工企业"采矿—选矿—磷酸—磷肥/磷饲料添加剂"整个链条磷流动特征、损失和利用效率;分析各种磷肥和饲料添加剂产品生产磷流动、利用效率和磷足迹;并利用情景分析提出提高磷利用效率的策略和优化潜力。结果表明:2015年该企业利用含3.902?106 t P2O5的自然矿石,生产了2.426?106 t(折纯P2O5,下同)磷复肥和磷饲料添加剂,其中磷酸二铵和磷酸一铵是最主要的产品,分别为156万t和54万t。磷酸二铵、磷酸一铵、重过磷酸钙、磷酸一二钙、普通过磷酸钙、复合肥、硫肥和磷酸二氢钾产品的生产效率分别为98%、98%、93%、95%、91%、99%、98%和91%,整个生产链条的生产效率为80%。大多数的磷资源在矿石加工部门损失掉,占磷损失量的51%;其次是矿石开采部门(25%)和磷酸生产部门(14%)。通过提高生产效率和废弃物利用率,磷资源损失预计可以减少42%。研究企业的磷利用效率在国内已达先进水平,但仍有提升潜力。  相似文献   

16.
4HJL-2型花生联合收获机摘果机构的设计与试验   总被引：5，自引：5，他引：0  
为适应4HJL-2型花生联合收获机摘果作业的要求,该文设计了一种螺旋圆弧面板式摘果机构,并对该4HJL-2型花生联合收获机中螺旋圆弧面板式摘果机构进行研究,通过试验建立了摘果机构参数与各试验指标之间的数学模型,并进行了动平衡和田间试验。结果表明,该螺旋圆弧面板式摘果机构可以对花生进行有效摘果,在最优工作参数：摘果搅龙长度168 cm、转速595 r/min、面板宽度47 cm时摘果率99.25%,破碎率0.234%,生产效率1 098.21 kg/h,均符合花生摘果机行业标准（NY/T 993-2006）,满足实际生产要求。研究结果可为花生联合收获机的开发研究提供参考。  相似文献   

17.
Chemical compositions and inhibitory effects of essential oils of Turkish oregano (Origanum minutiflorum O. Schwarz & P. H. Davis), bay laurel (Laurus nobilis L.), Spanish lavender (Lavandula stoechas subsp. stoechas L.), and fennel (Foeniculum vulgare Mill.) on Escherichia coli O157:H7, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus were determined. After the essential oils were applied on the foodborne pathogens at doses of 0 (control), 5, 10, 20, 30, 40, 50, and 80 microL/mL, the resultant numbers of cells surviving were counted. Results revealed that all essential oils exhibited a very strong antibacterial activity against the tested bacteria (P < 0.05). Gas chromatography-mass spectrophotometry analyses revealed that carvacrol (68.23%), 1,8-cineole (60.72%), fenchone (55.79%), and trans-anethole (85.63%) were the predominant constituents in Turkish oregano, bay laurel, Spanish lavender, and fennel essential oils, respectively.  相似文献   

18.
美人蕉(Canna.L)的辐射诱发突变   总被引：2，自引：2，他引：2  
本工作用60~(Co)γ射线及快中子处理美人蕉(Canna.L)休眠根茎,研究其辐射诱变规律,结果表明,γ射线处理的大花红美人蕉(Canna generalis Bai-ley)在VM_1代辐射效应十分明显,花色突变频率较高,其幅度在3.45—6％,适宜剂量为9.2—36.8Gy,不同基因型品种其辐射敏感性有明显差异。γ射线对美人蕉的诱变效果优于快中子,但连续几代重复照射的突变频率较低。应用γ射线处理大花红美人蕉共获得九个花色突变体,从中选育出三个花色各具特点的优良突变系,已繁育推广。  相似文献   

19.
用AMMI双标图分析糜子品种的产量稳定性及试点代表性   总被引：7，自引：1，他引：6  
为准确评价基因型和环境互作效应对糜子品种产量稳定性及试点对品种分辨力的影响,采用AMMI模型结合双标图和稳定性参数Dg(e)对第8轮(2006—2008年)国家糜子(粳性)品种区域试验的6个品种和9个试点的试验数据进行了分析。结果表明:基因型效应、环境效应和基因型×环境交互效应(G×E)均达到极显著水平,环境效应占总变异的52.85%,G×E交互效应占6.26%,基因型效应占2.76%。交互效应中IPCA1、IPCA2、IPCA3解释了92.58%基因与环境互作信息。试验也表明不同糜子品种在各试点的稳定性及不同试点对糜子品种的分辨力差异较大。6个参试品种中,"榆糜3号"(CK)、"伊8414-1-2-1"属于高产稳产型品种;"甘9109-6-1-1-2"、"固01-391"产量较高,但稳定性较差;"甘9133-1-3-4-1"稳产性好,但产量较低;"固02-25"产量低且稳定性差。在9个试点中,陕西府谷、宁夏同心、陕西榆林、内蒙赤峰4个试点对品种的分辨力较强,宁夏固原、宁夏盐池、甘肃会宁、山西五寨、内蒙鄂尔多斯5个试点对品种的分辨力较弱。  相似文献   

20.
Rapid, reliable and objective estimations of leaf area index (LAI) are essential for numerous studies of atmosphere–vegetation interaction, as LAI is very often a critical parameter in process-based models of vegetation canopy response to global environmental change. This paper reviews current knowledge concerning the use of direct and indirect methods for LAI determination. The value of optical LAI measurements by means of hemispherical photography has already been demonstrated in previous studies. As clumping seems to be the main factor causing errors in indirect LAI estimation, we suggest that the use of a digital camera with high dynamic range has the potential to overcome a number of described technical problems related to indirect LAI estimation. Further testing and defining of a standardised field protocol for digital hemispherical photography is however needed to improve this technique to achieve the standards of an ideal device.  相似文献   

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