山苍子精油深加工产品的生产途径

本文对山苍子精油深加工产品天然柠檬醛、紫罗兰酮、甲基紫罗兰酮、柠檬二乙缩醛,柠檬二甲缩醛,柠檬腈,环柠檬醛,维生素A,维生素E的生产路线、化学反应、产品质量指标及得率等方面作了较为系统的阐述。     

吉龙草精油的化学成分及抗菌活性研究

采用GC-MS方法对富含柠檬醛的吉龙草精油挥发性成分进行鉴定,共检测出62个成分,鉴定了其中55个成分。吉龙草精油主要化学成分为橙花醛(β-柠檬醛)、香叶醛(α-柠檬醛)、香芹酮、β-蒎烯等。试验也研究了吉龙草精油对大肠杆菌、金黄葡萄球菌、烟曲霉菌、白念珠菌的抗菌活性,结果显示这种精油对大肠杆菌、金黄葡萄球菌有明显的抗菌活性。     

山苍子精油及脂肪酸的利用

介绍了山苍子精油和脂肪酸的开发利用。山苍子精油可制取柠檬醛、紫罗兰酮、柠檬醛二乙缩醛、柠檬腈、α－环柠檬醛等香料原料；山苍子脂肪酸可制取酯类表面活性剂等精细化工产品。     

枯萎霉变对柠檬型香茅草精油得率和主成分含量的影响

采集广西防城港种植的柠檬醛型香茅草,对刚收割下来的香茅草枯萎叶稍、新鲜茎、新鲜全草、干燥全草的精油得率和成分进行分析,并考察自然存放霉变对香茅草精油得率和精油主要化学成分的影响。结果表明:在湿热环境下,随着存放时间的延长,香茅草腐烂程度加重,其精油得率降低,精油主要成分橙花醛和香叶醛总含量也降低。新鲜全草与干燥全草的含油率基本相同,新鲜香茅草精油中柠檬醛GC含量约为71.028%,得油率为0.483%,经过7天的自然腐烂后,霉变的香茅草精油中柠檬醛的GC含量降为66.1%,得油率为0.317%。新鲜茎精油柠檬醛GC含量78.766%为最高,枯萎叶稍精油得率最低为0.174%。     

枯萎霉变对柠檬型香茅草精油得率和主成分含量的影响北大核心

采集广西防城港种植的柠檬醛型香茅草,对刚收割下来的香茅草枯萎叶稍、新鲜茎、新鲜全草、干燥全草的精油得率和成分进行分析,并考察自然存放霉变对香茅草精油得率和精油主要化学成分的影响。结果表明:在湿热环境下,随着存放时间的延长,香茅草腐烂程度加重,其精油得率降低,精油主要成分橙花醛和香叶醛总含量也降低。新鲜全草与干燥全草的含油率基本相同,新鲜香茅草精油中柠檬醛GC含量约为71.028%,得油率为0.483%,经过7天的自然腐烂后,霉变的香茅草精油中柠檬醛的GC含量降为66.1%,得油率为0.317%。新鲜茎精油柠檬醛GC含量78.766%为最高,枯萎叶稍精油得率最低为0.174%。     

山苍子精油及脂肪酸的利用

介绍了山苍子精油和脂肪酸的开发利用。山苍子精油可制取柠檬醛、紫罗兰酮、柠檬醛二乙缩醛、柠檬腈、α－环柠檬醛等香料原料;山苍子脂肪酸可制取酯类表面活性剂等精细化工产品。     

合成柠檬醛

柠檬醛是一非环单萜烯,具有柠檬样香气,是重要香料原料之一,也是制取香草醇、紫罗兰酮及维生素A等的重要原料。从前,它是从天然精油(如柠檬草油、山苍籽油等)中分离而得,但其产量远不能满足需要。近年来,在国外已有合成柠檬醛出现,产量也迅速增长,有与天然品并驾齐驱的趋势。本文就它的主要合成方法作一简单介绍。合成柠檬醛的方法虽多,在工业上采用的一般有以下三种类型:(1)以丙酮为原料,经过中间产物甲基庚烯酮(Ⅱ),最后制得柠檬醛(Ⅰ);(2)以异戊二烯为     

从山苍子中提取柠檬醛及柠檬醛的测定研究

采用微波辐照技术从山苍子中提取制备柠檬醛,使山苍子精油的提取率较传统的直接水蒸气蒸馏法平均提高36.5%以上。用程序升温毛细管气相色谱归一化法测定山苍子精油中的柠檬醛,获得了山苍子精油柠檬醛含量为68.56%,标准偏差为0.28%,准确性与内标法相一致,而且操作较内标法和GB11424-89法更为方便的实验结果。     

山苍子精油及其开发利用

叙述了山苍子精油的提取，柠檬醛的单离，以及在柠檬腈、柠檬醛二乙缩醛、紫罗兰酮类香料方面的开发应用。     

从山苍子中提取柠檬醛及其测定研究

采用微波辐照从山苍子中提取柠檬醛 ,精油的得率较传统的直接水蒸气蒸馏法平均提高2 48%以上。用程序升温毛细管柱气相色谱归一化法测定山苍子精油中的柠檬醛 ,获得的山苍子精油柠檬醛质量分数为 6 8 6 4% ,回收率为 10 1 3% ,相对标准偏差为 0 2 8% ,线性相关系数为0 9997,准确性与内标法相一致 ,而且操作较内标法和GB 1142 4— 89法更为方便。     

Qualitative and Quantitative Changes in the Essential Oil of Lemon Verbena (Lippia citriodora) as Affected by Drying Condition

The objective of this study was to evaluate the effect of drying air temperature and air flow rate on the quantity and quality of the essential oil of lemon verbena. A completely randomized design was applied with a factorial arrangement of two factors: temperature (30, 40, and 50°C) and air flow rate (0.5, 1, and 1.5 m/s). The leaves were harvested in full blooming stage and placed in the drying machine at different temperatures and air flow rates. The essential oil of leaves was extracted by hydrodistillation in a Clevenger apparatus and analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC-MS). The results showed that the interaction between different temperatures under various air flow rates had a significant effect on the content and chemical composition of the essential oil. Seventeen compounds were identified in essential oil of lemon verbena, of which geranial, neral, and limonene were the major components. The maximum oil content and majority compounds of essential oil were obtained at 50°C and a 0.5 m/s air flow. Finally, seven mathematical models of thin-layer drying such as correlation coefficient (R ²), sum of square errors (SSE), and root mean square error (RMSE) were evaluated and the modified Page model was found to be the best drying model for lemon verbena.     

Toxic Effects of Lemon Peel Constituents on Ceratitis capitata

A series of experiments were conducted to evaluate the toxicity of lemon peel extracts incorporated into mediterranean fruit fly Ceratitis capitata diet. Extracts were obtained with different solvents: diethyl ether, ethyl acetate, and methanol. All three extracts were toxic to some extent; the diethyl ether extract was selected for further studies. Ether extracts of lemon peel were prepared weekly over a 2-month period, from fruits collected on the 1st d of the bioassay. Weekly GC-MS and UV analyses of the extracts demonstrated that the concentration of citral and coumarins decreased in the peel after harvest. We conducted a series of bioassays to evaluate the toxicity of the ether extract, and mixtures of this extract with citral, 5,7-dimethoxycoumarin. and linalool incorporated to C. capitata larvae's natural diet (lemon slices endocarp) at a concentration of 250 microg/g of diet. Significant larvicidal activity can be obtained from a fresh lemon peel extract; however, when the extract was obtained from stored lemons, toxicity decreased. Addition of small amounts of citral or 5,7-dimethoxycoumarin, and linalool to the stored lemon peel extract would bring back the toxicity to the rates of fresh lemons extracts. Finally, female adults of C. capitata fed on diets containing additional amounts of ether extract, 5,7-dimethoxycoumarin, and linalool, were exposed to different photoperiods to test for phototoxicity. The treatment was toxic and affected the oviposition capacity of females depending on photoperiod.     

大果木姜子茎挥发油化学成分分析及在卷烟中的应用

为研究大果木姜子茎挥发油成分及其对卷烟吸食品质的影响,采用水蒸气蒸馏法,从大果木姜子茎中提取挥发油,对主要化学成分进行GC-MS分析,并进行了卷烟加香试验。从挥发油中共鉴定出20个化合物,主要包括芳樟醇、D-苧烯、柠醛、（Z）-柠檬醛、6-甲基-5-庚烯-2-酮、（1S）-6,6-二甲基-2-亚甲基二环[3.1.1]庚烷、（-）-4-萜品醇、氧化芳樟醇、（＋）-α-松醇、1R-α-蒎烯等。评吸结果表明,大果木姜子茎挥发油对卷烟的香气质、香气量、余味、甜润感指标有一定改善作用。研究实,大果木姜子茎挥发油含有多种香味成分,在卷烟加香中具有一定的应用潜力。     

呋喃香豆素光化学毒性及其脱敏柑橘精油的研制

调查了柑橘类精油中普遍存在的呋喃香豆素类物质的种类、化学结构与分布,尤其是该类化合物对皮肤的光化学毒性作用。采用UV技术对市售芳香疗法用橙油、柠檬油、葡萄柚精油与佛手柑精油等四种柑橘类精油进行了光敏化合物呋喃香豆素含量测定,并使用液-液萃取分离技术实现了精油脱呋喃香豆素类生产性试验,开发研制了四种脱敏精油。这些脱敏精油在芳香疗法使用剂量下,其呋喃香豆素类化合物的含量控制在20ppm以下,保证使用的安全与可靠。     

不同工艺制得玫瑰精油香气差异对比分析

采用水蒸气蒸馏法、溶剂萃取法、超临界CO2萃取法提取玫瑰精油,采用气质联用技术对精油进行成分分析,结果表明,超临界CO2萃取法得到的玫瑰精油共有56种成分,以高级醇类和酯类为主,其中酯类相对质量分数是3种方法中最高的,为13%,特征清香成分相对质量分数为4.568%,总体上香气甜而饱满,拥有厚重优雅的底香,油脂味很淡,清香气息相对突出;水蒸气蒸馏工艺玫瑰精油含有60种成分,以高级醇类为主要成分,相对质量分数高达74.492%,主体香气成分相对质量分数最高,为72.057%,但苯乙醇的相对质量分数却只有0.711%,气息虽然香甜,但略显单薄,缺少蜜样香气;溶剂萃取玫瑰精油含有48种成分,以高级醇类和酯类为主要成分,烷酮类的相对质量分数较高,达到4.257%,所以油脂味较重,清香气息不突出,天然感较差.     

以柠檬醛为原料的香料合成研究进展

柠檬醛是一种很重要的香料化合物,是合成紫罗兰酮的主要原料,也是合成维生素A、甲基紫罗兰酮的主要原料,同时,柠檬醛还能合成柠檬腈、环状柠檬醛,香茅醇、橙花醇和香叶醇等重要的香料化合物,柠檬醛在香料工业中应用非常广泛。开展以柠檬醛为原料的合成研究对于开发利用我国的天然资源优势具有重要意义,综述了近二十年来以柠檬醛为原料的香料合成的研究进展。     

Citral Induces Auxin and Ethylene-Mediated Malformations and Arrests Cell Division in Arabidopsis thaliana Roots

Citral is a linear monoterpene which is present, as a volatile component, in the essential oil of several different aromatic plants. Previous studies have demonstrated the ability of citral to alter the mitotic microtubules of plant cells, especially at low concentrations. The changes to the microtubules may be due to the compound acting directly on the treated root and coleoptile cells or to indirect action through certain phytohormones. This study, performed in Arabidopsis thaliana, analysed the short-term effects of citral on the auxin content and mitotic cells, and the long-term effects of these alterations on root development and ethylene levels. The results of this study show that citral alters auxin content and cell division and has a strong long-term disorganising effect on cell ultra-structure in A. thaliana seedlings. Its effects on cell division, the thickening of the cell wall, the reduction in intercellular communication, and the absence of root hairs confirm that citral is a strong phytotoxic compound, which has persistent effects on root development.     

减压精馏法分离提取柠檬醛

采用间歇减式压精馏法,对从天然产物山苍子、柠檬草芳香油中分离提取柠檬醛工艺条件进行研究。获得适宜的工艺条件,分离得的单离柠檬醛含量最高达97%。另外从柠檬草油的轻度馏份中,分离得到高质量的月桂烯。     

山苍子油的精馏及柠檬醛的色谱研究

本文主要叙述了山苍子油分馏和柠檬醛的气相色谱分析方法 ,同时对采用不同精馏工艺条件对柠檬醛中同分异构体的组份和香气的影响作了讨论。并找到了合适的工艺参数