Isobornyl Acetate Research Articles

Study of Chemical Composition, Antibacterial and Antioxidant Activities of Rapistrum rugosum L. Essential Oils from Flowers, Leaves, and Stems

The chemical composition of the essential oils of three organs (flowers, leaves and stems) from Rapistrum rugosum (L.) All., was studied and screened for their possible antibacterial and antioxidant properties. According to the GC and GC/ MS analysis, 28 (represent 92.5 % of the total oil composition), 23 (93.9 %), and 38 compounds (94.3 %) were identified from flowers, leaves and stems, respectively. The major compound in the leaves essential oil was found to be pentadecanal (55.3 %) followed by hexahydrofarnesylacetone (8.4 %) and tetradecanoic acid (5.7%). While hexahydrofarnesylacetone (17.2 %) followed by 1-pentadecanol (8.3 %), tetradecanoic acid (5.9 %), (E)-β-damascenone (5.7 %) were the major compounds of the flowers oil. Tetradecanoic acid (13.1 %), hexahydrofarnesylacetone (10.1 %), dodecanoic acid (10.0 %), isobornyl acetate (7.6 %), 5-methylthiopentyl isothiocyanate (6.7 %) and (E)-β-ionone (6.2 %) were the main constituents for the stem essential oil. The essential oil of flowers exhibited the higher activity in each antioxidant system (ABTS, DPPH and β-Carotene-linoleic acid methods) with an important value for DPPH assay (PI = 69.88 ± 0.02 %). Furthermore, the isolated oils were tested against five Gram-positive and Gram-negative bacteria. It was found that the essential oil of all organs exhibited interesting antibacterial activities against Gram-positive bacteria, comparable to those of Gentamicin, which was used as positive control.

Insecticidal activity of the essential oil from Schizogyne sericea (Asteraceae) on four insect pests and two non-target species

Salado (Schizogyne sericea) is an aromatic shrub occurring very frequently in the coastal areas of Tenerife, Canary Islands. Herein, we investigated whether the essential oil produced by salado under salt stress could be effective as a botanical insecticide against a panel of target insects such as larvae and adults of the filariasis vector Culex quinquefasciatus, the peach-potato aphid Myzus persicae, the housefly Musca domestica and the tobacco cutworm Spodoptera littoralis. The essential oil, which was characterized by p-cymene, isobornyl acetate and thymol esters, as detected by gas chromatographic analysis, was highly effective against larvae of C. quinquefasciatus (LC50 of 49.1 mL.L−1) and adults of M. persicae (LC50 of 2.1 mL.L−1). On the other hand, little toxicity was found on adult females of C. quinquefasciatus and M. domestica, as well as on larvae of S. littoralis. Finally, the S. sericea essential oil was not toxic to selected non-target organisms, 3rd instar larvae and adults of the ladybug Harmonia axyridis or adults of the earthworm Eisenia fetida. Overall, the present research supports a possible use of salado oil in eco-friendly insecticidal formulations useful to manage culicine larval populations as well as M. persicae aphids.

Phytochemical composition and bioactivities of essential oils from six Lamiaceae species

Essential oils isolated from the Lamiaceae species are attracting increasing interest because of their applications in natural food preservation and pharmaceutics. The aim of this study was to systematically investigate the composition and biological effects of six Lamiaceae essential oils. Approximately 106 components were identified by gas chromatography-mass spectrometry (GC–MS), and the predominant compounds were linalool (0.05–46.55%), α-pinene (0.12–45.35%), o-cymene (0.91–41.20%), patchouli alcohol (28.27%), dl-menthol (21.12%), isobornyl acetate (22.52%), d-limonene (0.01–18.42%), α-terpineol (0.07–4.88%), and β-pinene (0.08–2.03%). Most of these essential oils were found to have effective antioxidant activities (IC50; 1.07–18.77%), as estimated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assays. The essential oils not only had antibacterial activities (6.5–12.3 mm diameter inhibition zones), but also had antifungal activities (6.5–19.0 mm diameter inhibition zones). The essential oils exhibited strong anti-inflammatory activities and markedly decreased the production of tumor necrosis factor (TNF-α), nuclear factor-kappa B (NF-κB), interleukin 6 (IL-6), and cyclooxygenase 2 (COX-2). The most abundant compounds in the essential oils isolated from the six Lamiaceae species have potential applications in the scavenging of free radicals, inhibition of bacterial and fungal growth, and relief from inflammation.

Insecticidal contact toxicity of several essential oils against stored product pests: Poster

Results of laboratory bioassays in Petri dishes on evaluation of contact toxicity of Illicium verum, Artemisia absinthium and Abies sibirica essential oils (EOs) against larvae of khapra beetle, Trogoderma granarium Ev., adults of grain weevil, Sitophilus granarius L., and rice weevil, Sitophilus oryzae L., and confused flour beetle, Tribolium confusum Duv., and larvae and adults of the lesser mealworm, Tenebrio molitor L., are presented. EOs commercial samples from retail pharmacy were tested at doses 0.01, 0.25, 0.50, 0.75 and 1.00 µl/cm2. A treated Petri dish surface treted with acetone was used as a control. The experiment was carried out in triplicate. Mortality of insects was assessed after 1, 3, 6 and 24 hours post exposure. After exposure insects were placed into untreated Petri dishes for 3 days. The main components of the A. absinthium EOs are thujil alcohol (19.65%), phellandrene (16.71%), borneol (12.1%) and thujone (11.55%) was found. The major component of I. verum EOs was anethole (98.64%). Isobornyl acetate (57.25%), a-pinene (13.55%) and limonene (10.62%) were found as the main components of A. sibirica EOs. S. oryzae and S. granarius were most sensitive to each EO. I. verum EOs was the most effective and caused 100% mortality of each insect at the dose 0.25 µl/cm2.

Continuous synthesis of isobornyl acetate catalyzed by a strong acid cation exchange resin in an oscillatory flow reactor

Recently, the application of continuous reaction technology for the production of fine chemicals has expanded significantly. Despite the increasing interest in continuous flow manufacturing, most industries continue to use multipurpose batch or semi-batch reactors. In this work, the utilization of a continuous oscillatory flow reactor(OFR) for heterogeneous catalysis is demonstrated by conducting a typical acetylation reaction (the acetylation of camphene) Parallel experiments was also performed in a batch stirred tank reactor (BSTR), and the results were compared with those obtained in the OFR. The temperature inside the OFR was uniform than that inside the BSTR, and the residence time distribution in the former system was close to that in a plug flow reactor. In addition, the OFR exhibited higher reaction rate and selectivity values than those obtained for the BSTR. Although the liquid was refreshed faster inside the OFR and no polymer residue was formed on the catalyst surface, its application required the screening of catalysts grains, which increased the probability of surface cracking. The OFR for continuous flow catalysis can serve as a promising starting point in the development of new, low-cost, and more efficient reactors for the synthesis of pharmaceuticals and other fine chemicals.

Antioxidant Activity of Several Essential Oils from Different Rosmarinus officinalis Cultivars Grown in Sanremo (Italy)

The evaluation of the essential oil (EO) profile of several cultivars of Rosmarinus officinalis, usually not used for food, and the assessment of their antioxidant activity as potential sources of natural antioxidants were studied in this work. Five different cultivars of Rosmarinus officinalis: R. officinalis ‘Alba'; R. officinalis ‘Blue Rain'; R. officinalis ‘Corsican Blue'; R. officinalis ‘Israeli'; R. officinalis ‘Majorca Pink’ and one hybrid of rosemary, Rosmarinus x lavandulaceus Noë, cultivated at CREA Sanremo (Italy), were hydrodistilled separately and the obtained EOs were analysed by GC-MS. Monoterpenes predominated in all the EO profiles but oxygenated monoterpenes were the most abundant constituents in R. officinalis ‘Blue Rain’, R. officinalis ‘Corsican Blue’, R. officinalis ‘Israeli’ and R. officinalis ‘Majorca Pink’. R. x lavandulaceus Noë and R. officinalis ‘Alba’ showed percentages of monoterpene hydrocarbons and oxygenated monoterpenes very similar. α-pinene, camphene, 1,8-cineole, camphor, borneol, verbenone, isobornyl acetate and β-caryophyllene were the main constituents present in all the plant cultivars, even though in different percentages. Myrcene predominate in R. officinalis ‘Alba’ (30.3 %), 1,8 cineol in R. officinalis ‘Blue Rain’ and R. officinalis ‘Israeli’ (21.9% and 26.4%, respectively), while camphor was the main constituent in R. officinalis ‘Majorca Pink’ (42.5%) and in R. x lavandulaceus (24.2%). R. officinalis ‘Corsican Blue’ showed similar amount of the three main components, verbenone, camphor and isobornyl acetate (18.5% >18.2% >15.4%, respectively). All the EOs were also tested for their antioxidant activity using the ferric reducing antioxidant power (FRAP) method and the stable radical DPPH. R. x lavandulaceus Noë showed the highest antioxidant activity, two folds more than that observed in R. officinalis ‘Israeli’.

MAO-A Inhibitory Potential of Terpene Constituents from Ginger Rhizomes-A Bioactivity Guided Fractionation.

Background: In the search for novel antidepressive drug candidates, bioguided fractionation of nonpolar constituents present in the oleoresin from ginger rhizomes (Zingiber officinale Roscoe, Zingiberaceae) was performed. This particular direction of the research was chosen due to the existing reports on the antidepressive properties of ginger total extract. The search for individual metabolites acting as MAO-A inhibitors, which correspond to the apparent effect of the total extract, is the subject of this work. Methods: Hexane extracts from ginger rhizomes were fractionated by using column chromatography (including silica gel impregnated with silver nitrate) and semi-preparative high-performance chromatography. For the activity assessment, an in vitro monoamine oxidase A (MAO-A) inhibition luminescence assay was performed on 10 purified terpenes: 1,8-cineole, α-citronellal, geraniol, β-sesquiphellandrene, γ-terpinen, geranyl acetate, isobornyl acetate, terpinen-4-ol, (E,E)-α-farnesene, and α-zingiberene. Results: Geraniol and (−)-terpinen-4-ol were found to be the strongest enzyme inhibitors with inhibition of 44.1% and 42.5%, respectively, at a concentration of 125 µg/mL. No differences in the inhibition potential were observed for the different groups of terpenes: sesquiterpenes, monoterpenes, or sesquiterpene alcohols; however, the two most active compounds contained a hydroxyl moiety. Conclusions: Terpene constituents from ginger’s extract were found to exhibit moderate inhibitory properties against the MAO-A enzyme in in vitro tests.

CHROMATOGRAPHIC BEHAVIOR OF BORNYL ACETATE DIASTEREOMERS UNDER THE CONDITIONS OF REVERSED-PHASE HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC)

The present paper illustrates the results of the study on chromatographic behavior and optimization of some parameters of the method of quantitative determination of bornyl acetate and isobornyl acetate diastereomers under the conditions of reversed-phase high- performance liquid chromatography. Chromatography was performed with HPLC platform Agilent 1200 with diode-matrix detector and a column Agilent Zorbax XDB, Extend-C18. Detection of the studied analytes was performed at a wavelength of 210 nm. Determinationof the concentration of bornyl acetate isomers was carried out in mixture with other components of the Abiessibirica essential oil in chromatographic systems with mobile phases of acetonitrile-water or isopropyl alcohol-water. The range of analyte concentrations in a sample was varied from 2 to 430 mg/ml for bornyl acetate and from 2 to 950 mg/ml for isobornyl acetate. It is stated that in a chromatographic system with a mobile phase, based on acetonitrile, the peaks of the studied components have an asymmetric shape, and the retention times of analytes increase with the decrease of their concentrations in a sample. In a chromatographic system with isopropyl alcohol the asymmetry of the bornyl acetate peak disappears, the width decreases and the retention time stabilizes. For isobornyl acetate a peak width also decreases, its asymmetry is preserved, but at the same time, the asymmetry coefficient takes on permitted values (less than 2). Calibration charts for the mentioned compounds in the used eluents are linear throughout the studiedconcentration range with correlation coefficients of R2>0.998. Thus, the conducted researches allow to recommend the reversed-phaseHPLC variant for the separate quantitative determination of bornyl acetate and isobornyl acetate in the pine oil samples.

Salvia broussonetii Benth.: aroma profile and micromorphological analysis

The volatile profiles (VOC) and the essential oil (EO) composition from the aerial parts of Salvia broussonetii were analysed. Sesquiterpene hydrocarbons dominate the VOCs from leaves (95.7%) and flowers (67.6%), followed by monoterpene hydrocarbons (2.6 and 29.7%, respectively). The main common compounds are germacrene D, β-bourbonene, α-pinene, α-copaene and α-gurjunene, even if with divergent relative abundances. In the leaf EOs the sesquiterpenes prevail, even if not overwhelmingly (about 50.0%), followed by monoterpenes (23.0–35.0%) and by minor fractions of diterpene hydrocarbons and non-terpene derivates. The most abundant common compounds across the two sampling periods are α-pinene, β-pinene, isobornyl acetate, α-gurjenene, germacrene D and bifloratriene. A morphological characterisation of the trichomes responsible for the productivity in terpenes was also performed. Four different morphotypes were observed on the above ground organs of S. brussonetii: peltates and capitates of type II and III resulted the only producers of volatile substances.

Ionic Liquids as Catalysts for the Acetylation of Camphene

[bnmim]HSO4 and [bnpy]HSO4 are active and environmentally friendly catalysts for the acetylation of camphene with acetic acid. The reaction provides isobornyl acetate with 100% selectivity and 72-86% yield. The effect of temperature, molar ratio camphene/acetic acid, and catalyst loading were investigated. The catalyst can be reused four times without loss of activity. Isobornyl acetate is an important fine chemical and has been used in the field of fragrance, medicine, organic synthesis and cosmetics [1]. It is an intermediary in the synthesis of camphor [2]. Usually it is prepared by an acid-catalized reaction of camphene with acetic acid or acetic anhydride. But this process has serious drawbacks such as the corrosion of equipment, non-recyclability of the catalyst and serious environmental pollution. In the face of increasing environmental requirements, the use of such catalysts becomes unacceptable. Therefore many studies have recently focused on the development of "clean" (green) processes for the production of terpene derivatives with high selectivity. For this purpose, heteropolyacids [3, 4], zeolites [5, 6], solid acid catalysts [7, 8], ion-exchange resin [9-11] were used as catalysts for synthesizing terpene esters. However, these catalysts have drawbacks such as a large ratio of catalyst/substrate, fast deactivation and a selectivity that leaves much to be desired. In the recent years ionic liquids (IL) have been investigated by many researchers as catalysts for different reactions. Due to its low volatility, negligible vapor pressure, reasonable thermal stability, outstanding recyclability and reusability, ionic liquids may be a viable alternative to widely applicable catalysts in the processes of modern synthetic chemistry, the green chemistry [12]. The improvement of the versatility of ionic liquids was achieved by creating acidic functionalized ionic liquids and combining the properties of a reagent and solvent [13]. A number of such ionic liquids were synthesized and successfully applied in the esterification reaction [14-17]. Received that the structure of the IL cation determines the direction of the rearrangement of terpene, whereas the nature of the anion affects the selectivity of the reaction [18, 19]. In the present work, we report the acetylation of camphene with acetic acid catalyzed by imidazolium and pyridinium ionic liquids (Scheme 1). The influence of various reaction parameters, such as the temperature, the molar ratio of camphene/acetic acid and catalyst loading, on the activity of the most active catalyst is also studied.

Oral 1-Generation Rat Reproduction Study of Isobornyl Acetate: An Evaluation Through Sexual Maturity in the F1 Generation.

Reproductive toxicity of isobornyl acetate (IA), a widely used fragrance ingredient, was investigated in a 1-generation reproduction study in which 25 Crl: CD (Sprague-Dawley) rats/sex/group were gavaged with dosages of 0 (corn oil vehicle), 30, 100, or 300 mg/kg/d during premating, mating, gestation, and lactation. After weaning, 25 F1 generation pups/sex/dosage group were randomly selected for evaluation until sexual maturity. The following parameters were evaluated in P generation males and females: viability, clinical signs, body weights, feed consumption, mating and fertility, organ weights, gross and microscopic observations, sperm assessments (motility and concentration), natural delivery and litter observations, and ovarian follicle counts. In F1 generation pups, viability, body weights, sexual maturation, anogenital distance (days 1 and 22 postpartum), nipple eruption (day 12 postpartum), and gross necropsy observations were recorded. Isobornyl acetate did not adversely affect any of the investigated parameters. Based on the results of this investigation, the no observable adverse effect level (NOAEL) for toxicity of IA is considered to be 300 mg/kg/d. Increased incidences of excess salivation occurred in P generation male and female rats at 100 and/or 300 mg/kg/d throughout the dosage period, and low incidences of urine-stained abdominal fur were seen in females at 300 mg/kg/d during the gestation period. These clinical signs were not considered as adverse effects of IA administration. Thus, the NOAEL for reproductive toxicity in the P generation rats and the NOAEL for viability and growth of the F1 generation offspring is considered to be ≥300 mg/kg/d.

Phytotoxic activities of essential oils and hydrosols of Haplophyllum tuberculatum

Phytotoxic properties of plants and their compounds against other plants or seeds are being increasingly reported. Moreover, essential oils may provide a new source of phytotoxic agents with possibly novel mechanisms of action. The aim of this study is to determine the chemical composition of the leaves, stems and leaves+stems essential oils by GC/MS and to assess their phytotoxic activities extracted from Haplophyllum tuberculatum A. Juss. (Forssk) as well as of the aromatic water obtained from these parts and of the roots. The phytotoxic activities of the essential oils and hydrosols were evaluated against Triticum aestivum L. and Raphanus sativus L. seeds. The GC–MS analysis revealed the presence of limonene, cis-p-menth-2-en-1-ol, trans-p-menth-2-en-1-ol, cis-piperitol, trans-piperitol, 1-octyl acetate, piperitone and isobornyl acetate as major compounds. Phytotoxic results showed that the assayed stems essential oils were active on the roots inhibition (IC50=1.09mg/mL) for wheat. Leaves+stems essential oils had a significant activity against the tested seeds with IC50 ranged from 0.70 to 1.46mg/mL for radical and epicotyls/coleoptiles percentage inhibition against T. aestivum L. and R. sativus L. While the hydrosols of leaves, stems and leaves+stems inhibited seeds germination at a higher concentration. The essential oils of this plants cannot be used as biologic herbicide with these cultivated plants.

Chromatographic Fingerprints Combined with Chemometric Methods Reveal the Chemical Features of Authentic Radix Polygalae.

GC-MS fingerprints of Radix Polygalae (RP) were measured for deliberately collected samples. A total of 88 volatile components were identified and quantified by subwindow factor analysis, heuristic evolving latent projection, and retention index. Next, an efficient discrimination model based on partial least-squares (PLS) discriminant analysis (DA) was developed to distinguish the superior RP samples from the inferior ones, and the reliability and predictive ability of the model was evaluated by cross-validation and permutation tests. Furthermore, four components (1-octanol, shyobunone, isobornyl acetate, and α-asarone) were screened by coefficient β of PLS-DA. They represented the important chemical features of authentic RP and could be applied to the accurate discrimination and QC of RP in the future. Our results suggest that chromatographic fingerprints coupled with chemometric methods provide an effective and convenient strategy for QC of RP and are helpful for revealing the chemical features of a complex analytical sample.

СОВРЕМЕННЫЕ НАПРАВЛЕНИЯ МЕДИКАМЕНТОЗНОЙ ТЕРАПИИ ХРОНИЧЕСКОГО ГЕНЕРАЛИЗОВАННОГО ПАРОДОНТИТА

The review deals with the analysis of modern methods of treatment of chronic generalized parodontitis from the perspective of differentiated principle of treatment of this disease. Particular attention is paid to methods of medical treatment, their diversity on the efficiency and mechanisms of therapeutic effects to select appropriate treatment, taking into account all the individual characteristics of the patient, aetiology, pathogenesis and severity of chronic generalized parodontitis. It has been demonstrated that an important aspect to achieve high efficiency of treatment is a method of drug delivery. The most effective method is a transmembrane dialysis, which makes it possible simultane-ously to obtain the maximum concentration of the therapeutic substances in the inflammatory focus and to eliminate from the inflammatory focus the low-medium weight tissue decomposition products, products of metabolism, while maintaining factors of regeneration and protection against infection. It has been evinced the advantages of sanogenetic therapy using vitamin cocktail and some higher plants BAS containing terpenoids (bornylacetate and its semisynthetic stereoisomer – isobornyl acetate), as the least toxic, having analgesic and anti-bacterial properties comparable with antibiotics, and capable to stimulate repair processes. The good water solubility of these substances provides ample pos-sibility of using these drugs in the form of solutions for rinsing, transmembrane dialysis, as liquid at ultrasonic curettage.

RIFM fragrance ingredient safety assessment, isobornyl isovalerate, CAS registry number 7779-73-9

This material was evaluated for genotoxicity, repeated dose toxicity, developmental toxicity, reproductive toxicity, local respiratory toxicity, phototoxicity/photoallergenicity, skin sensitization potential, as well as, environmental safety. Data from the suitable read across analog isobornyl acetate (CAS # 125-12-2) show that this material is not genotoxic, provided a MOE > 100 for the repeated dose, developmental and reproductive endpoints, and does not have skin sensitization potential. The local respiratory toxicity endpoint was completed using the TTC (threshold of Toxicological Concern) for a Cramer Class II material (0.47 mg/day). The phototoxicity/photoallergenicity endpoint was completed based on suitable UV spectra. The environmental endpoint was completed as described in the RIFM Framework.

Variation of Chemical Composition in Flowers and Leaves Essential Oils Among Natural Population of Tunisian Glebioniscoronaria (L.) Tzvelev (Asteraceae).

The aim of this study was to assess the percentage and constituents variations in flowers and leaves essential oil of three Glebioniscoronaria (L.) Tzvelev population, growing wildly in three different ecotypes (Utique, M'saken, and Sahara Lektar) in Tunisia. The chemical compositions of these essential oils were analyzed by the GC and GC/MS systems. Qualitative and quantitative differences were recorded between essential oils extracted from plants collected from the three geographical provinces and between organs of the same plant (leaves and flowers). In fact, 161 components representing 87.2-96.5% of the whole oils were identified. Myrcene (3.2-35.7%), (Z)-β-ocimene (0.6-23.0%), camphor (0.6-17.2%), cis-chrysanthenol (0-6.9%), cis-chrysanthenyl acetate (1.1-17.9%), isobornyl acetate (1.6-3.5%), (E)-β-farnesene (0-6.0%), germacrene D (0-8.7%), and (E,E)-α-farnesene (0.7-12.4%) were the predominant components in the oils. These major constituents occur in different amounts depending on the organs (leaves or flowers) and the geographical origin of the plant. The chemotaxonomic usefulness of these data was discussed according to results of principal component analysis (PCA). The scores, together with the loadings, revealed a different chemical pattern for each population.

Modulation of Human Neutrophil Responses by the Essential Oils from Ferula akitschkensis and Their Constituents.

Essential oils were obtained by hydrodistillation of the umbels+seeds and stems of Ferula akitschkensis (FAEOu/s and FAEOstm, respectively) and analyzed by gas chromatography and gas chromatography-mass spectrometry. Fifty-two compounds were identified in FAEOu/s; the primary components were sabinene, α-pinene, β-pinene, terpinen-4-ol, eremophilene, and 2-himachalen-7-ol, whereas the primary components of FAEOstm were myristicin and geranylacetone. FAEOu/s, β-pinene, sabinene, γ-terpinene, geranylacetone, isobornyl acetate, and (E)-2-nonenal stimulated [Ca(2+)]i mobilization in human neutrophils, with the most potent being geranylacetone (EC50 = 7.6 ± 1.9 μM) and isobornyl acetate 6.4 ± 1.7 (EC50 = 7.6 ± 1.9 μM). In addition, treatment of neutrophils with β-pinene, sabinene, γ-terpinene, geranylacetone, and isobornyl acetate desensitized the cells to N-formyl-Met-Leu-Phe (fMLF)- and interleukin-8 (IL-8)-induced [Ca(2+)]i flux and inhibited fMLF-induced chemotaxis. The effects of β-pinene, sabinene, γ-terpinene, geranylacetone, and isobornyl acetate on neutrophil [Ca(2+)]i flux were inhibited by transient receptor potential (TRP) channel blockers. Furthermore, the most potent compound, geranylacetone, activated Ca(2+) influx in TRPV1-transfected HEK293 cells. In contrast, myristicin inhibited neutrophil [Ca(2+)]i flux stimulated by fMLF and IL-8 and inhibited capsaicin-induced Ca(2+) influx in TRPV1-transfected HEK293 cells. These findings, as well as pharmacophore modeling of TRP agonists, suggest that geranylacetone is a TRPV1 agonist, whereas myristicin is a TRPV1 antagonist. Thus, at least part of the medicinal properties of Ferula essential oils may be due to modulatory effects on TRP channels.

Chemical composition and toxicity of Moroccan Tetraclinis articulata and Juniperus phoenicea essential oils against Aphis citricola Goot, 1912 (Homoptera, Aphididae)

Aphids cause significant damage tp crops, particularly citrus. To combat these pests, farmers typically use synthetic pesticides, yet these pesticides leave negative impacts on the environment. In an effort to find new efficient forms of control against aphids, especially Aphis citricola, without causing damage to the environment, we evaluated the toxicity of essential oil from the leafy twigs of Tetraclinis articulata and Juniperus phoenicea. Essential oil extraction was performed by steam distillation, and chemical composition was analyzed by gas chromatography–mass spectrometry (GC–MS). Thirty-six components were identified in the essential oil from T. articulata. Isobornyl acetate (58.32 %), α-pinene (9.31 %), and camphor (9.23 %) are the main components of this oil. For J. phoenicea, forty-seven compounds were identified; α-pinene was the major compound at 48.18 %, followed by δ-cadinene (6.61 %). Each of the essential oils we tested showed some degree of toxicity against A. citricola. This toxicity is amplified with concentration and time, and varies between plant species. Ultimately, the essential oil extracted from J. phoenicea’s leafy twigs was the most toxic (54.03 μL/L after 24 h) against A. citricola; its compounds may therefore be considered as new biodegradable agents to control aphids and viable for use in an integrated pest management program.

Chemical analysis of the essential oils from Schizogyne sericea growing in different areas of Tenerife (Spain)

Schizogyne sericea, also known as ‘salado’, is a halophytic species widespread throughout all the Canary Islands (Spain), being more common in Tenerife and Gran Canaria. The plant has been traditionally used as analgesic, astringent, anti-inflammatory and vulnerary. The aim of this work was to investigate the chemical variability in the volatile profiles obtained from the flowering aerial parts of S. sericea harvested in different localities (Palm Mar, Los Roques and La Barranquera) of Tenerife characterized by different microclimates. For the purpose, the essential oils were hydrodistilled from the dried aerial parts by a Clevenger-type apparatus and analysed by GC–MS. A similar chemical composition for the essential oil samples from the different geographic areas was obtained. The aromatic monoterpene hydrocarbon p-cymene (43.0–57.0%) was by far the main component of the essential oils, with minor amounts of isobornyl acetate (4.5–11.0%), limonene (4.7–5.6%), β-pinene (0.7–5.3%), α-phellandrene (2.2–4.8%) and camphene (1.8–4.5%). Interesting to note was the occurrence of thymol derivatives. That may be considered important chemotaxonomic markers of the genus Schizogyne, and, more in general, of the tribe Inulae. The volatile chemical profile obtained for S. sericea was similar to that of Schizogyne glaberrima previously studied.

Chemical Composition and Antibacterial Activity of the Essential Oil of Kauri Pine [ Agathis robusta (C. Moore ex F. Muell.) F.M. Bailey] from India

Agathis robusta (C. Moore ex F. Muell.) F.M. Bailey, commonly known as Queensland Kauri or smooth-barked Kauri, is a coniferous tree in the family Araucariaceae. This study aimed to investigate the chemical composition and antibacterial activity of the essential oil of A. robusta from India. The hydrodistilled resin and leaf essential oils were analyzed using GC-FID and GC-MS. Altogether, 34 constituents (forming 98.2% of the resin oil) and 43 constituents (forming 91.2% of the leaf oil composition) were identified. Major constituents of the resin oil were isobornyl acetate (37.9%), limonene (12.3%), bornyl acetate (7.4%), and myrtenol (5.8%), while the leaf oil contained β-selinene (18.1%), rimuene (14.2%), caryophyllene oxide (11.5%), spathulenol (10.5%), α-selinene (9.8%), and γ-muurolene (5.8%) as main constituents. The resin essential oil showed minimum inhibitory concentration (MIC) in the range of 250–500 μg/mL and minimum bactericidal concentration (MBC) in the range of 500 to >1000 μg/mL against pathogenic strains of eight bacteria.