芳香植物资源现状及其开发利用

基于国内外有关芳香植物的研究成果, 概述芳香植物的概念、分类和开发利用现状, 总结影响芳香植物生长、发育及其精油产量和品质的环境因素, 分析温度、光照、营养、植物种植模式等对芳香植物生长、发育的影响及其可能的机理, 介绍芳香植物在环境美化、香化、意境化以及杀菌、空气净化和身心保健等方面的研究成果以及目前国内外芳香植物的主要应用形式.     

土壤中多环芳烃不同前处理分析方法的比较

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。     

气相色谱法检测辐照牛肉中的碳氢化合物

利用气相色谱法分析牛肉辐照前后碳氢化合物的类型与浓度差异,建立了一种能判别辐照牛肉的鉴定方法。本试验通过正己烷溶剂萃取,Florisil柱分离和气相色谱分析,对辐照牛肉产生的6种碳氢化合物进行了定性和定量分析。研究结果表明,牛肉经辐照处理后,显著产生1,7-C16:2(1,7-十六二烯),而在未辐照的牛肉中没有检测到,因而1,7-C16:2是鉴定牛肉是否经过辐照处理的最适合标志物。     

Impact of low-molecular-weight organic acids on the availability of phenanthrene and pyrene in soil

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 (f_oc) 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 (K_d) 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.     

白玉兰与望春玉兰花香成分和含量的比较研究

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.     

Separation of aromatics compounds during the clarification of lemon juice by cross-flow filtration

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.     

3种菊科植物香气成分的热脱附气质联用分析

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     

野外长期污染土壤中残留多环芳烃的提取

[目的]准确定量野外污染土壤中残留的PAHs,为PAHs污染土壤的修复提供依据。[方法]针对长期石油污水灌溉农田土壤,对比了常用PAHs提取方法（索氏、震荡和超声提取方法）的提取效率差异。[结果]索氏提取法对土壤中总PAHs的可提取量最高（6 873.7μg/kg）,其次为往复震荡提取法（6 698.8μg/kg）,超声提取法最低（5 737.6μg/kg）,约为前2种提取方法的84%左右;相对于其他提取方法,索氏提取对4环和6环PAHs的提取效率最高,震荡提取对2环和5环PAHs的提取效率最高,超声萃取仅对3环PAHs提取效率最高。[结论]该研究为野外污染土壤中残留PAHs定量评价方法的选择提供了技术支持。     

芳香植物源营养液对梨树的抑菌和营养效应

 【目的】为有机果品生产提供一种制作简便、成本低廉的芳香植物源营养抑菌制剂的制作方法,探讨喷施该营养液对梨树的抑菌和营养效应。【方法】以芳香植物孔雀草、紫苏、神香草、薄荷、香矢车菊地上部分为材料,经发酵制成营养液,以分别喷施上述5种芳香植物源营养液（Tr1—Tr5）、5种植物的混合营养液（Tr6）为处理,喷施南国春氨基酸叶面肥（Tr7）和清水（Tr8）为对照（CK）,检测其对二年生盆栽南水梨/杜梨幼树黑星病、轮纹病、腐烂病的抑菌效果及营养生长、叶片养分含量的效果。【结果】芳香植物源营养液田间叶面喷施和实验室抑菌试验均对梨树黑星病、轮纹病和腐烂病有显著的抑菌效果;田间叶面喷施5种芳香植物源营养液与南国春氨基酸叶面肥均能显著地促进新梢生长,提高叶面积,提高叶片矿质元素含量（除P元素外）;其中喷施神香草营养液（Tr3）对于南水梨幼树生长发育的促进作用较显著;喷施孔雀草营养液（Tr1）和薄荷营养液（Tr4）对梨树病害的抑制效果较显著。【结论】田间叶面喷施芳香植物源营养液能够提高梨叶片养分含量,改善营养生长状况,有效抑制梨黑星病、轮纹病、腐烂病害的发生。     

珠江口伶仃洋水域沉积物中多环芳烃及其生态风险评价

为了研究珠江口伶仃洋水域沉积物中多环芳烃(PAHs)的分布特征、来源及评价PAHs对海洋生物的生态风险,于2010年6月采集珠江口伶仃洋水域20个站位的表层沉积物,采用GC-MS分析方法对沉积物中的16种PAHs含量进行分析测定。研究结果表明:珠江口伶仃洋水域沉积物中16种多环芳烃总含量范围是143.90~522.67 ng/g,平均含量287.05 ng/g,与国内外发达地区相比,该水域沉积物中PAHs污染处于中等水平。本实验采用目前较为常用的比值法(如荧蒽/芘、芘/苯并(a)芘)对调查区域沉积物中的PAHs来源进行分析研究,结果表明,大部分站位沉积物中的PAHs可能主要来源于石油污染,仅一小部分站位PAHs来源于煤等化石燃料的燃烧。利用效应区间低中值法评价珠江口伶仃洋水域沉积物中PAHs的生态风险,结果表明,在所设的20个站位中,有3个站位处的沉积物中的苊和芴对生物可能具有一定的生态风险,而其他站位沉积物中所有PAHs的含量均未达到生态风险评价标准,可以确定该水域沉积物中PAHs对生物具有潜在生态风险的可能性很小;有9个站位处的沉积物中的茚并(1,2,3-c,d)芘对生物可能存在生态风险;利用平均效应中值商法评价PAHs对珠江口伶仃洋水域的生态风险,认为所有站位处PAHs对生物体的潜在的综合生态风险的可能性较小。