Octyl Acetate Research Articles

Reevaluation of the sex pheromone of the lesser date moth, Batrachedra amydraula, using autosampling SPME-GC/MS and field bioassays

In a previous study of the sex pheromone of the lesser date moth, Batrachedra amydraula, using laboratory females, (Z4,Z7)-4,7-decadien-1-yl acetate, Z4-decen-1-yl acetate, Z5-decen-1-yl acetate and decyl acetate were identified by sequential SPME-GC/MS analysis. Traces of Z5-decen-1-ol were detected only in airborne collections. Concomitant field tests and re-evaluation of the composition of the sex pheromone of B. amydraula with feral female moths, using an improved sequential SPME-GC/MS procedure revealed a complex mixture of candidate pheromonal compounds. The same unsaturated acetates and the corresponding alcohols: (Z4,Z7)-4,7-decadien-1-ol, Z4-decen-1-ol, Z5-decen-1-ol were positively identified. In addition, the corresponding aldehydes, octanol and octyl acetate were also detected. All compounds were found to be released in a circadian rhythm, in a narrow time window of 2 h, approximately 1 h before sunrise. Comprehensive field bioassays indicated that the optimal attractive blend is a three-component mixture of (Z4,Z7)-4,7-decadien-1-yl acetate, Z5-decen-1-yl acetate and Z5-decen-1-ol in a ratio of 1:2:2. This blend gave about fivefold higher trap catch of B. amydraula males as compared to the previously published binary blend of (Z4,Z7)-4,7-decadien-1-yl acetate and Z5-decen-1-yl acetate in a ratio of 1:2. The alcohol Z5-decen-1-ol is an essential synergistic component of the sex pheromone of B. amydraula. All other identified compounds are inert, being neither synergists nor inhibitors of the pheromone. The optimal pheromone blend will be a useful tool in monitoring and control of B. amydraula, which is a serious pest of date plantations throughout the Middle East and northern Africa.

Chemical Composition and Antimicrobial Activity of Essential Oil of Heracleum rigens

The essential oil was extracted from the seeds of Heracleum rigens by hydrodistillation and a total of twenty compounds accounting for 98.5% of the total oil composition were identified. Physicochemical properties and chemical composition of the oil was determined by a combination GC/FID and GC/MS analysis. The major compounds identified were bornyl acetate (51.2%), alpha-pinene (22.6%), limonene (9.62%), octyl acetate (3.94%), rho-cymene (2.85%) and gamma-terpinene (1.93%). The antimicrobial activity of the oil was screened by the disc diffusion method against nine pathogenic bacterial strains. Maximum antimicrobial activity was noted against Klebsiella pneumonia and Bacillus subtillis. This investigation corroborates the traditional claim of H. rigens as an effective antimicrobial agent.

Determination of α-pinene and octyl acetate contents in Boswellia serrata

To establish method for determining the contents of alpha-pinene and octyl acetate in Boswellia serrata, in order to provide preference for making quality standards for B. serrata and processed B. serrata. Application of orthogonal design was employed to optimize the solvent, solvent quantity and extraction time. The GC-MS analysis was performed on a Rxi-5ms silica capillary column, running in the electron impact (EI) mode, with ion trap and injector temperature of 200 degrees C and 250 degrees C, respectively. The column oven was initially 50 degrees C and was held for 1 min after injection, followed by temperature ramping at 5 degrees C x min(-1) up to 130 degrees C, holding for 1 min. 1 microL of samples solution were injected in the split mode (1:60). Helium was the carrier gas. The mass spectrometer was set to scan m/z 45450 with an ionizing voltage at 70 eV. Sample solutions were prepared for 50-fold dose by ultrasonic extraction with hexane for 30 min. The content of alpha-pinene and octyl acetate in 10 batches of B. serrata were 0.021 3-0.149 5, 2.519 6-9.098 0 mg x g(-1), respectively. And, those of alpha-pinene and octyl acetate in processed B. serrata were 0.015 9-0.065 9, 0.801 0-12.812 2 mg x g(-1). The method is a stable and reliable for determining the contents of alpha-pinene and octyl acetate in B. serrata.

ChemInform Abstract: Superelectrophilic sp3 C—H Carbonylation of n‐Octyl Acetate as a Way to New Bifunctional neo‐Octanes.

Carbonylation of n -octyl acetate in the presence of CBr 4 ·2AlBr 3 followed by treatment with nucleophiles such as alcohols, amines or (het)arenes affords 7-acetoxy-2,2-dimethylheptanoyl-containing products.

Chemistry, pharmacology and medicinal properties of Heracleum persicum Desf. Ex Fischer: A review

Heracleum persicum is known as Persian Hogweed. H. persicum extracts and essential oil are important areas in drug development with numerous pharmacological activities in the Middle East especially in Iran. For a long time H. persicum has been used in traditional medicines for the relief of flatulence, stomachs as well as flavoring, as a digestive and an antiseptic. H. persicum has recently been shown to have antioxidant, anticonvulsant, analgesic, anti-inflammatory and immunomodulatory activities. Pimpinellin, isopimpinellin, bergapten, isobergapten and sphondin are furanocoumarins which are reported from roots of this plant. Hexyl butyrate, octyl acetate and hexyl-2-methylbutanoate were identified as the major constituents for H. persicum essential oil. Due to the easy collection of the plant and being widespread and also remarkable biological activities, this plant has become both food and medicine in Iran. This review presents comprehensive analyzed information on the botanical, chemical and pharmacological aspects of H. persicum. Key words: Heracleum persicum, Apiaceae, antioxidant, anticonvulsant, anti-inflammatory.

Grape Contribution to Wine Aroma: Production of Hexyl Acetate, Octyl Acetate, and Benzyl Acetate during Yeast Fermentation Is Dependent upon Precursors in the Must

Wine is a complex consumer product produced predominately by the action of yeast upon grape juice musts. Model must systems have proven ideal for studies of the effects of fermentation conditions on the production of certain wine volatiles. To identify grape-derived precursors to acetate esters, model fermentation systems were developed by spiking precursors into model must at different concentrations. Solid-phase microextraction-gas chromatgraphy mass spectrometry analysis of the fermented wines showed that a variety of grape-derived aliphatic alcohols and aldehydes are precursors to acetate esters. The C6 compounds hexan-1-ol, hexenal, (E)-2-hexen-1-ol, and (E)-2-hexenal are all precursors to hexyl acetate, and octanol and benzyl alcohol are precursors to octyl acetate and benzyl acetate, respectively. In these cases, the postfermentation concentration of an acetate ester increased proportionally with the prefermentation concentration of the respective precursor in the model must. Determining viticultural or winemaking methods to alter the prefermentation concentration of precursor compounds or change the precursor-to-acetate ester ratio will have implications upon the final flavor and aroma of wines.

Chemical composition of volatile compounds and antioxidant activities of essential oil, aqueous and ethanol extracts of wild Tunisian Ruta chalepensis L. (Rutacea)

The chemical composition of the volatile fractions of two populations of Ruta chalepensis L. (Rutaceae) collected, at the vegetative stage, from two areas of the South-East of Tunisia (Sdira and Thoujene) were analysed. The volatile fractions were extracted from the leaves by hydrodistillation or static headspace, then analysed by gas chromatography flame ionization detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS). Octyl acetate (24.22 to 33.16 %), 2-undecanone (12.43 to 23.82%) and 2-nonanone (14.11 to 41.69%) were found to be major components of the volatiles extracted by hydrodistillation or head space method.Minor components revealed by hydrodistillation were not detected by head space extraction. However, hexadecanoic acid (10.2%) and di(ethylhexyl) phthalate (12.73%) were detected only in headspace of R. chalepensis leaves from Thoujene. Unlike the essential oil, the ethanol andthe aqueous extracts revealed interesting antioxidant activities including 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, reducing power and metal (Fe2+) chelating activity and could be considered as important sources of natural antioxidants. Key words: Ruta chalepensis, hydrodistillation, headspace, ketones, esters, antioxidant activity.

Water-Stable All-Biodegradable Microparticles in Nanofibers by Electrospinning of Aqueous Dispersions for Biotechnical Plant Protection

Pheromone eluting oligolactide (OLA) microcapsules immobilized in electrospun biodegradable polyester nanofibers were obtained by electrospinning of aqueous dispersions of the microcapsules. OLA was prepared by conventional melt polycondensation of lactic acid. Following the protocol of the solvent displacement method, OLA was dissolved in acetone and mixed with Brij S20 and the pheromone of the European grape vine moth, Lobesia Botrana, (E,Z)-7,9-dodecadien-l-yl acetate (DA). Up to 32 wt % of this mixture could be dispersed in water with colloidal stability of several weeks without any sedimentation. Without DA as well as OLA, no stable dispersions of OLA in water were obtained. Replacement of DA by classical hydrophobes typically used for miniemulsions did not yield stable dispersions, but the addition of octyl acetate, which shows structural similarity to DA, yielded stable dispersions in water up to 10 wt %. Dispersions of OLA/DA were successfully electrospun in combination with an aqueous dispersion of a biodegradable block copolyester resulting in water-stable nanofibers containing OLA/DA microcapsules. Release of DA from microcapsules and fibers was retarded in comparison with non-encapsulated DA, as shown by model studies.

响应面分析法优化乙酸正辛酯制备工艺研究

采用响应面分析法优化酸性离子液体催化制备乙酸正辛酯的工艺条件。在单因素实验的基础上，选取反应时间、酸醇物质的量比、带水剂用量和催化剂用量4个因素进行Box–Behnken中心组合设计。实验结果表明，带水剂量与催化剂用量的相互作用和反应物物质的量比和离子液体剂量的相互作用最大；离子液体1-甲基-3-(丙基-3-磺酸基)咪唑硫酸氢盐([HSO3-pmim]HSO4)催化合成乙酸正辛酯的最佳反应条件为：反应时间1 h，n(乙酸):n (正辛醇) = 1:1.8，离子液体剂量5%，带水剂用量10 mL，在该条件下，乙酸正辛酯的酯化率为95.4%，与模型预测值基本相符。[HSO3-pmim]HSO4离子液体在催化乙酸正辛酯制备过程中具有良好的催化活性和稳定性。 Response surface methodology (RSM) was applied to optimize the synthesis of octyl acetate from n-octanol catalyzed by acidic ionic liquid. Based on the single factor experiments, Box-Behnken central composite design was adopted to investigate the effects of various reaction conditions, including reaction time, alcohol/acid mole ratio, amount of water carrying agent, the amount of ionic liquid and their interactions on the esterification. The analysis from Design-Expert showed that the interactions between the amount of water carrying agent and the catalyst dosage, the molar ratio and the amount of ionic liquid were the strongest. The optimum conditions were as follows: reaction time 1 h, n(acetic acid):n(n-octanol) = 1:1.8, ionic liquid 5% of acid and the amount of water carrying agent 10 mL. Under the optimized conditions, the yield of octyl acetate reached 95.4%, in close agreement with values predicted by the mathe- matical model. [HSO3-pmim]HSO4 ionic liquid showed the good catalytic properties and stability on the esterification of n-octanol with acetic acid.

响应面分析法优化乙酸正辛酯制备工艺研究<br>Optimization of Process Variables in the Synthesis of Octyl Acetate by Response Surface Methodology

响应面分析法优化乙酸正辛酯制备工艺研究<br>Optimization of Process Variables in the Synthesis of Octyl Acetate by Response Surface Methodology

Temperature Dependence of Ion Transport in Dilute Tetrabutylammonium Triflate-Acetate Solutions and Self-Diffusion in Pure Acetate Liquids

Conductivities and static dielectric constants for 0.0055 M tetrabutylammonium trifluoromethanesulfonate in n-butyl acetate, n-pentyl acetate, n-hexyl acetate, n-octyl acetate, and n-decyl acetate have been collected over the temperature range of 0-80 °C. Self-diffusion coefficients and static dielectric constants of pure acetates were obtained over the same temperature range. Both temperature-dependent diffusion coefficients and ionic conductivities of these pure acetates and dilute acetate solutions can be accurately described by the compensated Arrhenius formalism. Activation energies were calculated from compensated Arrhenius plots for both conductivity and diffusion data. Activation energies are higher for conductivity data of 0.0055 M TbaTf-acetates compared to diffusion data of pure acetates. The plot of the exponential prefactor versus the dielectric constant yields a single master curve for both conductivity and diffusion data. These data support the argument that mass and charge transport are thermally activated processes in the acetates, as previously observed in alcohol-based electrolytes.

Superelectrophilic sp3 C–H carbonylation of n-octyl acetate as a way to new bifunctional neo-octanes

Carbonylation of n -octyl acetate in the presence of CBr 4 ·2AlBr 3 followed by treatment with nucleophiles such as alcohols, amines or (het)arenes affords 7-acetoxy-2,2-dimethylheptanoyl-containing products.

Evaluation of the use of Syzygium cumini fruit extract as an antioxidant additive in orange juice and its sensorial impact

This work is an exploratory study of the possibility of promoting the consumption of Syzygium cumini fruit by adding its extract to orange juice making good use of its functional (antioxidant) properties. S. cumini fruit extract was characterized in terms of its anthocyanin content (2.11 g/100 g expressed in cyanidine-3-glucoside equivalents), total phenolic compounds (360 mg/100 g expressed in gallic acid equivalents) and antioxidant capacity evaluated by the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging method. The effects of the addition of S. cumini fruit crude extract as well as its chromatographic fractions on the juice were assessed chemically by headspace solid-phase micro-extraction and gas chromatography coupled with a mass spectrometry detector. Only six compounds had their chromatographic peak intensities clearly changed and the results are discussed in terms of the inhibition of the formation of 2-octanone, hexanol, α-copaene, and α-panasinsene and the conservation of octyl acetate and p-menth-1-en-9-ol. Sensory evaluation of orange juice with and without S. cumini crude extract addition did not show any significant differences in the sensorial profile, discriminative and acceptance tests.

Chemical composition, antibacterial and antifungal activities of essential oil from Heracleum Siamicum Craib

Heracleum siamicum Craib (Apiaceae), is an important herbal species having wide application in food flavoring processes. The flat-oval shaped fruit of H. siamicum Craib from North Thailand was hydrodistilled, and the chemical composition of the essential oil was analyzed by GC and GC-MS. The essential oil yield based on dried plant material was 1.25%, and twenty-five compounds (corresponding to 97.69% of the total weight) were identified. The main components were: n-octyl acetate (65.30%), o-cymene (10.35%), limonene (7.52%), δ-2-carene (6.87%), cis-thujone (1.92%), isobornyl acetate (0.94%), n-octanol (0.73%), 1,8-cineol (0.62%), n-tridecanol (0.44%), and safrole (0.37%). H. siamicum essential oil demonstrated bactericidal and fungicidal activity against five bacterial strains and two fungal strains, as evaluated using agar diffusion in terms of the minimum inhibitory concentration.

Efficient carbonyl hydrosilylation reaction: Toward EVA copolymer crosslinking

AbstractIn this article, the hydrosilylation reaction of carbonyl groups of acetate derivatives and SiH groups of hydride‐terminated polydimethylsiloxane at high temperature (100–130 °C) are described. Triruthenium dodecacarbonyl, Ru3(CO)12, was used as effective catalyst for hydrosilylation reaction. The hydrosilylation reactions with octyl acetate and 4‐heptyl acetate were investigated by multinuclear NMR spectroscopy (1H, 13C, and 29Si). This work provides evidence of the addition reaction of SiH groups onto carbonyl groups. The influence of the nature of the acetate structure on the reaction kinetics was shown and the slight contribution of side reactions at high temperature highlighted. Hydrosilylation reaction was extent to the crosslinking of ethylene‐vinyl acetate (EVA) copolymer in the same range of temperature. The formation of EVA chemical network was demonstrated by HR‐MAS NMR spectroscopy and by measuring the gel fraction of EVA chains in hot toluene. From Flory theory, the crosslinking density of elastic strand was calculated to be 80 mol m−3 in agreement with the measurements from swelling ratio (VA/SiH molar ratio: 11.8). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011

GC-MS analysis of volatile oil of olibanum

To analyze the volatile oil of olibanum and apply scientific evidences for its applications. The volatile oil was analyzed by GC-MS. One hundred components were identified,accounting for 91.26% of the total volatile oil, and the main components were octyl acetate, beta-elemene. It contains some transdermal absorption enhancers. The components of olibanum volatile oil were complicated; the connatural transdermal absorption enhancers make it possible to use in external preparation.

The effects of acetates of aliphatic alcohols on the cholinergic nerve structures and the acetylcholine receptor of the guinea-pig ileum.

Abstract Isoamyl acetate, n-butyl acetate, n-amyl acetate and n-propyl acetate produced contractions of the isolated ileum of the guinea-pig. These were inhibited by atropine, procaine and by cooling. These acetates and also s-butyl, t-butyl and n-octyl acetate behaved as inhibitors of acetylcholine at 14 ± 1°. The acetylcholine content in the organ bath fluid increased after 60 min incubation of the ileum with isoamyl acetate. The results indicated that the agonistic acetates produced contraction of ileum through the liberation of acetylcholine from the cholinergic nerve-endings. All the acetates behaved as inhibitors of acetylcholine when they combined with the acetylcholine receptor on the muscle.

Comparison of Chemical Composition of Essential Oil and n-Hexane Extracts of Zosimia absinthifolia (Vent.) Link

The water distilled essential oils and n-hexane extract of Zosimia absinthifolia (Vent.) Link. (family: Umbelliferae) growing in Khalkhal, North-west Iran were analyzed by GC and GC-MS. The yields were: 0.2 % and 0.7 % (v/w) for essential oil and n-hexane extracts, respectively. Twenty-one compounds representing 96.0 % of the distilled oil of Z. absinthifolia were identified, among them octyl acetate (24.7 %), β-caryophyllene (22.2 %), cis-β-ocimene (8.9 %), α-pinene (5.3 %), clovane (5.3 %) and β-gurJunne (4.6 %) were the major constituents. The extracts was characterized by higher amount of butyl octanoate (31.4 %), octyl acetate (29.7 %), 6-methoxy-1- indanone (12.2 %) and osthol (4.4 %), sixteen components comprising 95.1 % of the total oil were detected in the extract. The oil obtained by hydrodistillation method consist mainly of aliphatic oxygenated and sesquiterpene constituents, whereas the extracts contain mainly aliphatic ester compounds.

Analyses of the Headspace Volatile Constituents of Aerial Parts of Zosimia radians Boiss. and Hohen and Flowers, Leaves and Stems of Zosimia absinthifolia (Vent.) Link. by Solid-Phase Microextraction

The present study describes the volatile composition of headspace from aerial partsof Zosimia radians Boiss. & Hohen. which is endemic to Iran and flowers, leaves and stems of Zosimiaabsinthifolia (Vent.) Link., were investigated through solid-phase microextraction method by GCMS.The volatile of Z.radians was characterized by higher amount of octyl acetate (58.8 %). In theflower volatile of Z. absinthifolia also octyl acetate (58.4 %) and octanol (25.0 %) were the predominantcompounds. The volatile composition from leaf and stem of the plant were rich in germacrene D (22.5% and 18.5 %), β-caryophyllene (18.1 % and 10.5 %) and bicyclogermacrene (11.2 %, 7.6 %)respectively. The other main component of the stem was cis-chrysanthenyl acetate (15.5 %). Theflower volatile of Z. absinthifolia consisted mainly of aliphatic compounds, while in leaf and stemvolatile of the plant sesquiterpenes predominated over monoterpenes.

Odorant-binding proteins of the malaria mosquito Anopheles funestus sensu stricto.

BackgroundThe mosquito Anopheles funestus is one of the major malaria vector species in sub-Saharan Africa. Olfaction is essential in guiding mosquito behaviors. Odorant-binding proteins (OBPs) are highly expressed in insect olfactory tissues and involved in the first step of odorant reception. An improved understanding of the function of malaria mosquito OBPs may contribute to identifying new attractants/repellents and assist in the development of more efficient and environmentally friendly mosquito controlling strategies.MethodologyIn this study, a large screening of over 50 ecologically significant odorant compounds led to the identification of 12 ligands that elicit significant electroantennographic (EAG) responses from An. funestus female antennae. To compare the absolute efficiency/potency of these chemicals, corrections were made for differences in volatility by determining the exact amount in a stimulus puff. Fourteen AfunOBP genes were cloned and their expression patterns were analyzed. AfunOBP1, 3, 7, 20 and 66 showed olfactory tissue specificity by reverse transcriptase PCR (RT-PCR). Quantitative real-time PCR (qRT-PCR) analysis showed that among olfactory-specific OBPs, AfunOBP1 and 3 are the most enriched OBPs in female antennae. Binding assay experiments showed that at pH 7, AfunOBP1 significantly binds to 2-undecanone, nonyl acetate, octyl acetate and 1-octen-3-ol but AfunOBP3, which shares 68% identify with AfunOBP1 at amino acid level, showed nearly no binding activity to the selected 12 EAG-active odorant compounds.ConclusionThis work presents for the first time a study on the odorants and OBPs of the malaria vector mosquito An. funestus, which may provide insight into the An. funestus olfactory research, assist in a comparative study between major malaria mosquitoes An. gambiae and An. funestus olfactory system, and help developing new mosquito control strategies to reduce malaria transmission.