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Juan Eugenio Álvaro María Teresa Lao Mourad Baghour Moumen Abdelmajid 《Journal of plant nutrition》2016,39(8):1057-1062
The growth and essential oil (EO) production of parsley were evaluated in response to salinity and nutrient solution concentrations in a soilless culture. Parsley plants that were 60 days old were potted in a coconut fiber and peat moss medium and were treated with four different nutrient solutions, including T1, T2, T3 and T4. The T1 nutrient solution was the standard, the T2 and T3 solutions contained incremental macronutrient concentrations with an electrical conductivity (EC) of up to 2.2 and 3.2 dS m?1, respectively, and the T4 solution was the same as T2 but with sodium chloride (NaCl) and an incremental macronutrient concentration with an EC of 3.2 dS m?1. Next, these plants were grown for 90 days in a greenhouse with natural daylight in Nador, Morocco. Shoot and root growth significant decreased with increasing EC. However, the salinity that resulted from the addition of NaCl did not affect plant growth in the nutrient solutions. The optimum obtained growth and EO production were 1.2 and 2.2 dS m?1, respectively. Consequently, the optimum EC value (based on the EO production) of parsley in the soilless culture was 1.2–2.2 dS m?1. 相似文献
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针对国内缺乏土壤中多环芳烃(PAHs)检测的国家标准方法的现状,以提取效率和回收率作为不同溶剂、不同提取方式前处理优劣的表征,研究了目前国内较常用的3种提取技术(索氏提取、超声波提取、水平振荡提取)和2种不同的提取剂(二氯甲烷、二氯甲烷/丙酮=5:1)对提取效率和回收率的影响。结果表明,以二氯甲烷作为提取溶剂,水平恒温振荡提取4h,可以有效地提取土壤中的15种多环芳烃类污染物。此技术提取时间短,节省提取溶剂且提取效率较高,方法回收率在73.3%-117.5%范围内。 相似文献
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Impact of low-molecular-weight organic acids on the availability of phenanthrene and pyrene in soil 总被引:1,自引:0,他引:1
Wanting Ling Yanzheng Gao Xuezhu Zhu Bingqing Sun 《Soil biology & biochemistry》2009,41(10):2187-2195
The impact of low-molecular-weight organic acids (LMWOAs) on the availability of phenanthrene and pyrene was investigated using laboratory batch assays. Experiments were conducted with two types of soil with different organic contents. The LMWOAs used were citric and oxalic acid. A mild solvent extraction procedure and a sorption-desorption experiment were used to predict the availability of phenanthrene and pyrene. Results showed that the extractable amounts of phenanthrene and pyrene in both soil types increased with increased citric or oxalic acid concentration. Citric acid addition promoted phenanthrene and pyrene extraction to a greater degree than oxalic acid. Compared with freshly spiked soils, the extractable amounts of phenanthrene and pyrene with the addition of LMWOAs decreased significantly after 60 days of cultivation. Soils with higher values of soil organic carbon content (foc) showed decreased phenanthrene and pyrene availability after the addition of LMWOAs. The sorption and desorption results also demonstrated the enhanced availability of PAHs with LMWOA addition. Phenanthrene sorption could be described using a linear model, regardless of the addition of LMWOAs. The simulated distribution constants (Kd) for phenanthrene sorption decreased significantly with the addition of LMWOAs. In contrast, phenanthrene desorption clearly increased with the addition of LMWOAs. These results suggest that the availabilities of phenanthrene and pyrene can be increased with the addition of suitable LMWOAs. 相似文献
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白玉兰与望春玉兰花香成分和含量的比较研究 总被引:1,自引:0,他引:1
采用顶空固相微萃取(HS-SPME)和气相色谱-质谱联用(GC-MS)技术分析了白玉兰和望春玉兰鲜花的芳香成分及相对含量,并对其进行了比较.结果表明,白玉兰和望春玉兰花香成分的种类及含量存在较大差异.白玉兰共检测出25种芳香成分,萜烯类化合物含量最高,达到了70.29%,是主要香气成分.含量较多的芳香成分有β-水芹烯、α-金合欢烯、桉叶油素、β-蒎烯、氧化芳樟醇和α-蒎烯;望春玉兰共检测出32种芳香成分,萜烯类化合物是主要香气成分,其相对含量为71.34%,含量较多的芳香成分有β-水芹烯、顺式-β-罗勒烯、桉叶油素、β-蒎烯、β-月桂烯和紫丁香醇D.不同的芳香物质及含量组成,使白玉兰和望春玉兰形成各自独特的香气类型. 相似文献
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D. Saura N. MartiM. Valero E. GonzálezA. Carbonell J. Laencina 《Industrial Crops and Products》2012,36(1):543-548
Tangential flow filtration was tested for clarifying lemon juice for the food industry. Membranes with three different pore sizes were assayed: 100,000 Da (polysulfone), 0.20 μm (polypropylene), and 0.45 μm (polyvinylidene difluoride). Volatiles were extracted using a distillation technique and quantified by gas chromatography-mass spectrometry. The concentration of aroma compounds finally found in the clarified lemon juice (CLJ) increased with the membrane pore size and more apolar compounds were found in the CLJ obtained by using more hydrophobic membranes. The low concentration of terpene hydrocarbons of the lemon juices clarified using membranes of 100,000 Da and 0.45 μm made them ideal as acidulant agents in fruit preservation. On the other hand, the CLJ obtained using a membrane of 0.2 μm of pore size, with high recuperation percentages for terpene hydrocarbons (e.g. limonene) and aldehydes (neral and geranial), made this juice ideal for applications in which a lemon flavor is needed.One of the main results of this work lies in the fact that certain compounds reduce their concentration in a large percentage during the cross-flow filtration. This reduction is associated with its presence in the juice cloud and pulp whose are concentrated in the retentate. The elimination of these compounds is transcendental to use lemon juice as an acidifier because they are responsible for aromatic degradation in processed food, as, for example, canned peach halves in syrup. Therefore, the use of cross-flow filtration in the clarification allows the use of lemon juice as acidulant in food with very sensitive flavors to degradation during processing and storage. 相似文献
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为了研究大花金鸡菊Coreopsis grandiflora,黑心菊Rudbeckia hirta和万寿菊Tagetes erecta香气成分的差异,从植物香气角度为3种菊科植物的园林配置提供理论依据,实验采用热脱附气质联用技术对3种菊科植物进行香气成分的分析。结果表明:从大花金鸡菊中鉴定出55种成分,主要为:α-蒎烯(相对含量23.43%),柠檬烯(22.75 %),水芹烯(4.37%),桧烯(3.78%)和月桂烯(3.56%);从黑心菊中鉴定出51种成分,主要为:水芹烯(31.36%),顺?鄄氧化芳樟醇(11.88%),桧稀(9.54%),壬醛(6.52%)和辛醛(5.08%);从万寿菊中鉴定出30种成分,主要为:萜品油烯(23.63%),罗勒烯(22.40%),柠檬烯(16.12%),石竹烯(6.36%)和反-罗勒烯(3.50%)。因此,香气成分及其相对含量的差异决定了3种菊科植物的香气表现。图1表1参23 相似文献