香叶油的化学成分

为了探讨不同产地香叶油的香气特徵,我们对云南省昆明、玉溪、石屏、宾川产香叶油和法国波尔蓬,埃及产香叶油的化学成分用Finnigan-4510型气相色谱/质谱/计算机联用方法进行了定性、定量分析,共分离鉴定了35个成分(见表2)。 分析结果表明:云南产香叶油的香气成分主要由香茅醇,甲酸香茅酯,香叶醇,玫瑰醚构成;而法国、埃及产香叶油的香气成分则主要由香叶醇,甲酸香叶酯,香茅醇,甲酸香茅酯和芳樟醇构成。二者具有不同的格调和香气特徵。     

Coupling of Metabolism and Bioconversion: Microbial Esterification of Citronellol with Acetyl Coenzyme A Produced via Metabolism of Glucose in an Interface Bioreactor

Microbial esterification of citronellol with acetyl coenzyme A (acetyl-CoA) produced via metabolism of glucose was performed with Hansenula saturnus IFO 0809 in an interface bioreactor by using a hydrophilic carrier (an agar plate or an agar-coated filter pad) and a hydrophobic organic solvent (decane). An increase in the glucose concentration on an agar plate led to a decrease in oxidation of citronellol and an increase in the amount of citronellyl acetate. Fed-batch addition of citronellol efficiently alleviated substrate toxicity and resulted in the accumulation of high levels of citronellyl acetate. Furthermore, triple coupling of acetyl-CoA formation, microbial reduction of citronellal to citronellol, and esterification of the resulting citronellol with acetyl-CoA was also an efficient way to prepare citronellyl acetate. By using coupling systems, citronellyl acetate could be efficiently produced without any acetyl donor.     

Volatile constituents of Trichothecium roseum

In the course of investigation of Trichothecium roseum (Fungi Imperfecti) for its attractancy against Tyrophagus putrescentiae (cheese mite), the twenty following volatile compounds produced at a very low concentration by the microfungus were identified by gc, gc/ms, gc/c.i.ms and tlc: 3-methyl-1-butanol, 3-octanone, 1-octen-3-one, 3-octanol, octa-1,5-dien-3 one, 1-octen-3-ol, 6-methyl-5-hepten-2-ol, octa-1,5-dien-3 ol, furfural, linalool, linalyl acetate, terpineol (alpha and beta) citronellyl acetate, nerol, citronellol, phenylacetaldehyde, benzyl alcohol geranyl acetate, 1-phenyl ethanol and nerolidol. Octa-1,5-dien-3-ol and octa-1,5-dien-3-one have not been previously isolated from fungi; octa-1,5-dien-3-ol is the most potent attractant amount the volatile compounds detected by gc.     

Composition of rugosa rose (Rosa rugosa thunb.) hydrolate according to the time of distillation

Rugosa rose (Rosa rugosa Thunb.) is one of the most common rose species in Poland. It has mild soil and climate requirements and is resistant to low temperatures. Rugosa rose hips are a valuable raw material used in food and pharmaceutical industries, while flowers and petals may be a source of fragrant products, such as essential oil and hydrolate. The main aim of this study was to verify usefulness of dried R. rugosa petals for essential oil and hydrolate production. We also assessed the use of rugosa rose petals remaining after oil distillation for hydrolate production.The R. rugosa dried petals immersed in water were subjected to simple distillation and five fractions of primary rose hydrolate were obtained. In parallel, essential oil from the second sample of petals was obtained by hydrodistillation in Clevenger-type apparatus. The distillation residue was used for obtaining four fractions of secondary hydrolate. The volatiles from hydrolate fractions were isolated by liquid–liquid extraction with diethyl ether. The essential oil and hydrolate volatiles were analyzed by GC–FID–MS.Hydrolate fractions contained similar amounts of volatiles (20–30 mg/L) with the exception of the first fraction of primary hydrolate (60 mg/L). β-Phenylethanol, citronellol, geraniol, and nerol were the main volatile constituents of primary hydrolate. β-Phenylethanol, citronellic acid, and geranic acid were the main volatile constituents of secondary hydrolate. The content of alcohols decreased, while the content of monoterpene esters (citronellyl, neryl, and geranyl acetate) as well as monoterpene acids (citronellic, neric, and geranic acid) increased in successive fractions of both hydrolates.The scent and composition of essential oil and hydrolate obtained from R. rugosa petals were similar to those of rose oil and rose water produced from damask rose (Rosa damascena Mill.). This proves, that rugosa rose distillation products may become an alternative to fragrant damask rose products.     

The Main Chemical Components of the Essential oil from Rosa rugosa Thunb

The plant of Rosa rugosa Thunb. now is cultivated widely in northern China and other places is characterized as Rosa rugosa cv 'Plena' with violet-redflowers, The essential oil extracted by steam distillation, from its flower is a famousfragrance: The flower can be used as medicine and food. The chemical components ofthis essential oil have been determined by chromatography, IR, DC-MS and other methods. Thirty components have been identified, such as β-citronellol, geraniol, geraniolacetate, citronellyl acetate, methyl eugenol, linalool etc. Their contents in the oil havebeen determined also. The chemical components of absolute oil have been determined byGC-MS. All these results can be used to compare with that of Rosa damascena Millfrom Bulgarian 'Valley cf rose and other Rosa sp.     

Repelling properties of some plant materials on the tick Ixodes ricinus L.

The repellent effects on nymphal stages of Ixodes ricinus L. of some plant materials have been studied in the laboratory. The plant material consisted of an ethanolic extract from Achillea millefolium L., and volatile oils of birch and/or pine tar, citronella, cloves, eucalyptus, geranium, lavender, lily of the valley and peppermint. The most pronounced effects were observed for the oils of citronella, cloves and lily of the valley. They possessed repelling activities of the same magnitude as the reference repellent DEET (N,N-diethyl-m-toluamide). Some major constituents of these oils, e.g. citronellol and geraniol (oil of citronella and lily of the valley) and eugenol (oil of cloves) showed pronounced repelling effects. This was also the case for phenethyl alcohol, a minor component in the oil from lily of the valley.     

Chemical composition of volatiles from cortical oleoresin of Pseudotsuga menziesii

Pseudotsuga menziesii cortical oleoresin was found to contain 1·7% of oxygenated terpenoids and compounds of similar volatility composed of linalool, methylsalicylate, bornyl acetate, citronellol, geranyl acetate, methylthymol, citronellyl acetate, terpinen-4-ol, borneol, isopulegol, anethole, terpinen-4-ol acetate, camphor, geraniol, neryl acetate, and nerol. Sesquiterpenoid hydrocarbons were low (only 0·07%) and contained sibirene and longifolene as main constituents, with β-caryophyllene, γ-muurolene, γ-cadinene (identified by IR), and 20 additional compounds in small amounts. p-Cymen-8-ene was identified in monoterpene hydrocarbon fraction.     

c-fos expression in the amygdala:In vivo antisense modulation and role in anxiety

Summary 1. The amygdaloid complex is a key structure in mechanisms of fear and anxiety. Expression of the immediate-early gene c-fos has been reported in the central nucleus of the amygdala following various stressors, but the functional role of this phenomenon has remained unknown.2. c-fos expression was observed in the central nucleus when rats were subjected to a pharmacologically validated animal model of anxiety, the Vogel conflict test, but not after mere exposure to the test apparatus. Bilateral amygdala injection of a 15-mer phosphorothioate c-fos antisense oligodeoxynucleotide prior to testing blocked conflict-induced c-fos expression and had behavioral effects similar to those of established antianxiety drugs.3. Separate experiments determined that antisense treatment did not affect conflict behavior by acting on shock thresholds or drinking motivation.4. These findings provide evidence that neuronal activation and c-fos induction in the amygdala may be of importance for mechanisms of fear and anxiety.     

Reversal of the anti-conflict action of valproate by various GABA and benzodiazepine antagonists

The effects of RO 15-1788, RO 5-3663, picrotoxin and bicuculline on the anti-conflict properties of valproate were studied in rats using a modified Vogel 's conflict test procedure. A low dose of the benzodiazepine (BDZ) antagonist, RO 15-1788 (5 mg/kg), blocked the anti-punishment properties of valproate (400 mg/kg), whereas no antagonism was observed after a high dose (25 mg/kg) of the BDZ antagonist. High doses of RO 5-3663 or picrotoxin also reversed the anti-conflict action of valproate. Bicuculline did not change the effects of valproate in this test situation. The suppressive effect of valproate on locomotor activity was reversed by a low dose (5 mg/kg) of RO 15-1788, but not by the other antagonists. RO 5-3663 was the only antagonist which effectively reversed the muscle relaxant effects of valproate observed in a Rotarod performance test. These findings indicate that various pharmacological actions of valproate may be due to a complex interplay with several sites at the GABA-BDZ-receptor complex.     

Citronellol and Geraniol,Components of Rose Oil,Activate Peroxisome Proliferator-Activated Receptor α and γ and Suppress Cyclooxygenase-2 Expression

We evaluated the effects of rose oil on the peroxisome proliferator-activated receptor (PPAR) and cyclooxygenase-2 (COX-2). Citronellol and geraniol, the major components of rose oil, activated PPARα and γ, and suppressed LPS-induced COX-2 expression in cell culture assays, although the PPARγ-dependent suppression of COX-2 promoter activity was evident only with citronellol, indicating that citronellol and geraniol were the active components of rose oil.     

Citronellol and geraniol, components of rose oil, activate peroxisome proliferator-activated receptor α and γ and suppress cyclooxygenase-2 expression

We evaluated the effects of rose oil on the peroxisome proliferator-activated receptor (PPAR) and cyclooxygenase-2 (COX-2). Citronellol and geraniol, the major components of rose oil, activated PPARα and γ, and suppressed LPS-induced COX-2 expression in cell culture assays, although the PPARγ-dependent suppression of COX-2 promoter activity was evident only with citronellol, indicating that citronellol and geraniol were the active components of rose oil.     

Antifungal action and antiaflatoxigenic properties of some essential oil constituents

The effect of 20 essential oil constituents on Aspergillus flavus growth and aflatoxin production was tested at the level of 1000 ppm. Some of the tested oils exhibited inhibitory effects on fungal growth and toxin formation. Five oils, namely geraniol, nerol and citronellol (aliphatic oils), cinnamaldehyde (aromatic aldehyde) and thymol (phenolic ketone), completely suppressed growth and aflatoxin synthesis. Trials for determining the minimum inhibitory concentration (MIC) of these oils revealed that geraniol, nerol and citronellol were effective at 500 ppm, while thymol and cinnamaldehyde were highly effective at doses as low as 250 and 200 ppm, respectively. It was observed that citral, citronellal and eugenol prevented fungal growth and toxin formation for up to 8 d. However, after 15 d of incubation, toxin production was greater than the controls.     

Anti-inflammation activities of essential oil and its constituents from indigenous cinnamon (Cinnamomum osmophloeum) twigs

In this study, chemical compositions of hydrodistilled essential oil and anti-inflammatory activities from the twigs of Cinnamomum osmophloeum Kaneh. were investigated for the first time. The chemical constituents of the twig essential oil were further analyzed by GC-MS and they were found to be L-bornyl acetate (15.89%), caryophyllene oxide (12.98%), gamma-eudesmol (8.03%), beta-caryophyllene (6.60%), T-cadinol (5.49%), delta-cadinene (4.79%), trans-beta-elemenone (4.25%), cadalene (4.19%), and trans-cinnamaldehyde (4.07%). The effects of essential oil on nitric oxide (NO) and prostaglandin E2 (PGE2) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophages were also examined. Results of nitric oxide tests indicated that twig essential oil and its major constituents such as trans-cinnamaldehyde, caryophyllene oxide, L-borneol, L-bornyl acetate, eugenol, beta-caryophyllene, E-nerolidol, and cinnamyl acetate have excellent activities. These findings demonstrated that essential oil of C. osmophloeum twigs have excellent anti-inflammatory activities and thus have great potential to be used as a source for natural health products.     

Studies on glucosinolate degradation in Lepidium sativum seed extracts

Analysis of Lepidium sativum seeds showed the presence of allyl, 2-phenethyl and benzyl glucosinolates, the first two being reported for the first time from this source. The effects of temperature, pH of the extraction medium and the length of time allowed for autolysis were assessed on the benzyl glucosinolate degradation products in seed extracts. In particulàr benzyl thiocyanate was not produced at higher temperatures but at ambient and lower temperatures it exceeded isothiocyanate. Nitrile was always the major product under the conditions studied, ever at pH levels as high as 7.4. Five new possible benzyl glucosinolate degradation products were detected and evidence is presented that benzaldehyde and benzyl alcohol could be secondary products formed thermally from isothocyanate and thiocyanate, respectively. Benzyl mercaptan and benzyl methyl sulphide also appear to be thermally produced.     

Generation of Phenylpropanoid Pathway-Derived Volatiles in Transgenic Plants: Rose Alcohol Acetyltransferase Produces Phenylethyl Acetate and Benzyl Acetate in Petunia Flowers

Esters are important contributors to the aroma of numerous flowers and fruits. Acetate esters such as geranyl acetate, phenylethyl acetate and benzyl acetate are generated as a result of the action of alcohol acetyltransferases (AATs). Numerous homologous AATs from various plants have been characterized using in-vitro assays. To study the function of rose alcohol acetyltransferase (RhAAT) in planta, we generated transgenic petunia plants expressing the rose gene under the control of a CaMV-35S promoter. Although the preferred substrate of RhAAT in vitro is geraniol, in transgenic petunia flowers, it used phenylethyl alcohol and benzyl alcohol to produce the corresponding acetate esters, not generated by control flowers. The level of benzyl alcohol emitted by the flowers of different transgenic lines was ca. three times higher than that of phenylethyl alcohol, which corresponded to the ratio between the respective products, i.e. ca. three times more benzyl acetate than phenylethyl acetate. Feeding of transgenic petunia tissues with geraniol or octanol led to the production of their respective acetates, suggesting the dependence of volatile production on substrate availability.     

超临界CO2萃取茉莉净油化学成分的研究

利用 GC和 GC- MS联用仪对超临界 CO2 萃取茉莉浸膏的净油进行化学成分分析 ,分离出 131个组分 ,鉴定出其中的 35个化合物 ,所鉴定的成分占分离成分的 85%以上。同时将分析结果与普通溶剂法制取的茉莉净油进行比较。     

Location and biosynthesis of monoterpenyl fatty acyl esters in rose petals

The upper epidermal layer of cells and the epicuticular wax surface of Lady Seton rose petals are sites of biosynthesis and accumulation, respectively, of a family of terpenyl fatty acyl esters. These esters are based mainly on the acyclic monoterpene alcohol geraniol coupled primarily to fatty acids of chain lengths 16-20 and in mass terms represent from 14% to 64% of the total monoterpenes present in the petals. The lipophilic nature of these non-volatile esters of the monoterpene alcohols contrasts with that of the lipophilic volatile parent alcohols themselves and with the hydrophilic, non-volatile, glucoside derivative of the other principal petal fragrant compounds, the phenylpropanoids, beta-phenyl ethanol and benzyl alcohol. These latter compounds are also synthesised and are resident in the petal. Biosynthetic studies confirmed that the petal upper epidermal cell layer has the capacity to incorporate mevalonic acid into the monoterpene component of the fatty acyl ester. The biosynthesis of the monoterpene component of the fatty acyl ester occurs via the mevalonic acid pathway in Lady Seton as well as in the hybrid tea rose Fragrant Cloud. In the latter flower the biosynthesis of geraniol was biosynthetically trans as was the formation of nerol and citronellol. Both geraniol and nerol were shown to be precursors of citronellol via an NADPH dependent reductase reaction. Oleic acid is assimilated into the acyl moiety of the terpenyl ester in Lady Seton isolated petal discs. It is probable that the lipophilic non-volatile terpenyl fatty acyl esters represent a stable storage form of the corresponding alcohols from their residency within the epicuticular wax layer. These acyl esters may realise, on hydrolysis, additional aroma notes from the living flower and potentially commercially significant quantities of the fragrant terpenols during oil of rose essence production.     

Potentiation of GABAA receptors expressed in Xenopus oocytes by perfume and phytoncid.

To study the effects of perfume and phytoncid on GABAA receptors, ionotropic GABAA receptors were expressed in Xenopus oocytes by injecting mRNAs that had been prepared from rat whole brain. Essential oil, perfume and such phytoncid as leaf alcohol, hinokitiol, pinene, eugenol, citronellol and citronellal potentiated the response in the presence of GABA at low concentrations (10 and 30 microM), possibly because they bound to the potentiation-site in GABAA receptors and increased the affinity of GABA to the receptors. Since it is known that the potentiation of GABAA receptors by benzodiazepine, barbiturate, steroids and anesthetics induces the anxiolytic, anticonvulsant and sedative activity or anesthetic effect, these results suggest the possibility that the intake of perfume or phytoncid through the lungs, the skin or the intestines modulates the neural transmission in the brain through ionotropic GABAA receptors and changes the frame of the human mind, as alcohol or tobacco does.     

蒙椴树叶挥发油成分的气相色谱-质谱分析

采用水蒸气蒸馏法对蒙椴树叶挥发油进行提取,挥发油回收率约为0.6%(w);用气相色谱—质谱联用技术对挥发性成分进行分析,鉴定了45个化合物,占挥发油成分的80.35%以上。其中主要有己醇,己烯醇,贝壳杉烯和苯甲酸等