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Concept: Essential oil


Postoperative nausea (PON) is a common complication of anesthesia and surgery. Antiemetic medication for higher-risk patients may reduce but does not reliably prevent PON. We examined aromatherapy as a treatment for patients experiencing PON after ambulatory surgery. Our primary hypothesis was that in comparison with inhaling a placebo, PON will be reduced significantly by aromatherapy with (1) essential oil of ginger, (2) a blend of essential oils of ginger, spearmint, peppermint, and cardamom, or (3) isopropyl alcohol. Our secondary hypothesis was that the effectiveness of aromatherapy will depend upon the agent used.

Concepts: Alcohol, Ethanol, Chemotherapy, Carbon, Anesthesia, Essential oil, Ginger, Oil


Lavender essential oils are predominantly constituted of regular monoterpenes, for example linalool, 1, 8 cineole and camphor. However, they also contain irregular monoterpenes including lavandulol and lavandulyl acetate. Although the majority of genes responsible for the production of regular monoterpenes in lavenders are now known, enzymes (including LPPS) catalyzing the biosynthesis of irregular monoterpenes in these plants have not been described. Here, we report the isolation and functional characterization of a novel cis prenyl diphosphate synthase cDNA, termed L. x intermedia lavandulyl diphosphate synthase (LiLPPS), through a homology based cloning strategy. The LiLPPS ORF, encoding for a 305 amino acids long protein, was expressed in E. coli and the recombinant protein was purified by NiNTA affinity chromatography. The ca. 34.5 kDa bacterially produced protein specifically catalyzed the head to middle condensation of two DMAPP units to LPP in vitro with apparent Km and kcat values of 208 microM and 0.1, respectively. LiLPPS is a homodimeric enzyme with a sigmoidal saturation curve and hill coefficient of 2.7, suggesting a positive cooperative interaction among its catalytic sites. LiLPPS could be used to modulate the production of lavandulol and its derivatives in plants through metabolic engineering.

Concepts: DNA, Protein, Amino acid, Metabolism, Enzyme, Escherichia coli, Essential oil, Lavender


BACKGROUND: Pelargonium graveolens (P. graveolens) L. is an aromatic and medicinal plant belonging to the geraniacea family. RESULTS: The chemical compositions of the essential oil as well as the in vitro antimicrobial activities were investigated. The GC-MS analysis of the essential oil revealed 42 compounds. Linallol L, Citronellol, Geraniol, 6-Octen-1-ol, 3,7-dimethyl, formate and Selinene were identified as the major components. The tested oil and organic extracts exhibited a promising antimicrobial effect against a panel of microorganisms with diameter inhibition zones ranging from 12 to 34 mm and MICs values from 0.039 to10 mg/ml. The investigation of the phenolic content showed that EtOAc, MeOH and water extracts had the highest phenolic contents. CONCLUSION: Overall, results presented here suggest that the essential oil and organic extracts of P. graveolens possesses antimicrobial and properties, and is therefore a potential source of active ingredients for food and pharmaceutical industry.

Concepts: Pharmacology, Water, Essential oil, Oil, Oils, Rose, Rose oil, Pelargonium graveolens


This article describes the various chemical components as obtained from the oils in the leaves of Cymbopogon citratus using hydrodistillation and solvent-free microwave extraction methods. Furthermore, extractions of the oils were also carried out with a slight in pH variation and compared, “GC-MS evaluation of C. citratus (DC) Stapf oil obtained using modified hydrodistillation and microwave extraction methods” (Ajayi et al., 2016 [1]). The current article contains one table exhibiting a list of compounds in the four different methods of extraction. Comparative studies amongst the various methods of extraction are highlighted in the table.

Concepts: Chemical compound, Essential oil, Oil, Oils, Cymbopogon, Cymbopogon citratus


The Asian citrus psyllid, Diaphorina citri Kuwayama, is the insect vector of the pathogen causing huanglongbing. We selected three botanical oils to evaluate behavioral activity against D. citri. In laboratory olfactometer assays, fir oil was repellent to D. citri females, while litsea and citronella oils elicited no response from D. citri females. In choice settling experiments, D. citri settled almost completely on control plants rather than on plants treated with fir oil at a 9.5 mg/day release rate. Therefore, we conducted field trials to determine if fir oil reduced D. citri densities in citrus groves. We found no repellency of D. citri from sweet orange resets that were treated with fir oil dispensers releasing 10.4 g/day/tree as compared with control plots. However, we found a two-week decrease in populations of D. citri as compared with controls when the deployment rate of these dispensers was doubled. Our results suggest that treatment of citrus with fir oil may have limited activity as a stand-alone management tool for D. citri and would require integration with other management practices.

Concepts: Water, Citrus, Liquid, Fruit, Orange, Hemiptera, Essential oil, Insect repellent


Patchouli is used as an incense material and essential oil. The characteristic odor of patchouli leaves results from the drying process used in their production; however, there have to date been no reports on the changes in the odor of patchouli leaves during the drying process. We investigated the aroma profile of dried patchouli leaves using the hexane extracts of fresh and dried patchouli leaves. We focused on the presence or absence of the constituents of the fresh and dried extracts, and the differences in the content of the common constituents. Fourteen constituents were identified as characteristic of dried patchouli extract odor by gas chromatography-olfactometry analysis. The structures of seven of the 14 constituents were determined by gas chromatography-mass spectrometry (α-patchoulene, seychellene, humulene, α-bulnesene, isoaromadendrene epoxide, caryophyllene oxide, and patchouli alcohol). The aroma profile of the essential oil obtained from the dried patchouli leaves was clearly different from that of dried patchouli. The aroma profile of the essential oil was investigated by a similar method. We identified 12 compounds as important odor constituents. The structures of nine of the 12 constituents were determined by gas chromatographymass spectrometry (cis-thujopsene, caryophyllene, α-guaiene, α-patchoulene, seychellene, α-bulnesene, isoaromadendrene epoxide, patchouli alcohol, and corymbolone). Comparing the odors and constituents demonstrated that the aroma profile of patchouli depends on the manufacturing process.

Concepts: Olfaction, Drying, Perfume, Odor, Essential oil, Aroma compound, Aromatherapy, Patchouli


Olfactory stimulation is an often overlooked method of environmental enrichment for cats in captivity. The best known example of olfactory enrichment is the use of catnip, a plant that can cause an apparently euphoric reaction in domestic cats and most of the Pantherinae. It has long been known that some domestic cats and most tigers do not respond to catnip. Although many anecdotes exist of other plants with similar effects, data are lacking about the number of cats that respond to these plants, and if cats that do not respond to catnip respond to any of them. Furthermore, much is still unknown about which chemicals in these plants cause this response.

Concepts: Felidae, Essential oil, Valerian, Nepeta, Dipsacales, Nepetalactone


Abstract Objectives: The objective of this pilot study was to determine the effectiveness of a mixture of essential oils (peppermint, basil, and helichrysum) on mental exhaustion, or moderate burnout (ME/MB) using a personal inhaler. Design: This was a randomized, controlled, double-blind pilot study. Data were collected 3 times a day for 3 weeks (Monday-Friday). The first week was baseline for both groups, the second week was intervention (aromatherapy or placebo), and the third week was washout. Settings/location: Participants used a personal inhaler at home or at work. Subjects: The subjects comprised a convenience sample of 13 women and 1 man who each had self-assessed ME/MB. Interventions: Participants were randomized to receive a personal inhaler containing either a mixture of essential oils or rose water (as used in Indian cooking). Outcome measures: The outcome measures were a 0-10 scale with 10=worst feeling of burnout, 0=no feeling of burnout. There was a qualitative questionnaire rating aroma and a questionnaire listing perceived stressors. Results: While both groups had a reduction in perception of ME/MB, the aromatherapy group had a much greater reduction. Conclusions: The results suggest that inhaling essential oils may reduce the perceived level of mental fatigue/burnout. Further research is warranted.

Concepts: Psychology, Effectiveness, Perception, Mind, Essential oil, Oil, Rose, Aromatherapy


ETHNOPHARMACOLOGICAL SIGNIFICANCE: Although no known medicinal use for Pittosporum undulatum Vent. (Pittosporaceae) has been recorded, anecdotal evidence suggests that Australian Aboriginal people used P. angustifolium Lodd., G.Lodd. & W.Lodd. topically for eczema, pruritis or to induce lactation in mothers following child-birth and internally for coughs, colds or cramps. AIMS OF THE STUDY: Essential oil composition and bioactivity as well as differential solvent extract antimicrobial activity from P. angustifolium is investigated here firstly, to partially describe the composition of volatiles released in traditional applications of P. angustifolium for colds or as a lactagogue, and secondly to investigate antibacterial activity related to topical applications. Essential oils were also investigated from P. undulatum Vent., firstly to enhance essential oil data produced in previous studies, and secondly as a comparison to P. angustifolium. MATERIALS AND METHODS: Essential oils were hydrodistilled from fruit and leaves of both species using a modified approach to lessen the negative (frothing) effect of saponins. This was achieved by floating pumice or pearlite obsidian over the mixture to crush the suds formed while boiling. Essential oil extracts were analysed using GC-MS, quantified using GC-FID then screened for antimicrobial activity using a micro-titre plate broth dilution assay (MIC). Using dichloromethane, methanol, hexane and H(2)O as solvents, extracts were produced from leaves and fruit of P. angustifolium and screened for antimicrobial activity and qualitative phytochemical character. RESULTS: Although the essential oil from leaves and fruit of P. undulatum demonstrated some component variation, the essential oil from fruits of P. angustifolium had major constituents that strongly varied according to the geographical location of collection, suggesting the existence of at least two chemotypes; one with high abundance of acetic acid decyl ester. This chemotype had high antimicrobial activity whilst the other chemotype had only moderate antimicrobial activity against the three microbial species investigated here. This result may support the occurrence of geographical specificity with regard to ethnopharmacological use. Antimicrobial activity screening of the solvent extracts from P. angustifolium revealed the leaves to be superior to fruit, with water being the most suitable extraction solvent. CONCLUSION: To the best of our knowledge, this study constitutes the first time essential oils, and solvent extracts from the fruits of P. angustifolium, have been examined employing comprehensive chemical and biological analysis. The essential oil composition presented in this paper, includes components with structural similarity as chemosemiotic compounds involved in mother-infant identification, which may have significance with regard to traditional applications as a lactagogue.

Concepts: Water, Ethanol, Petroleum, Acetic acid, Solvent, Essential oil, Oil, Indigenous Australians


Volatile compounds play a key role in determining the sensory appreciation of vegetable oils. In this study a systematic evaluation of odorants responsible for the characteristic flavour of roasted tigernut oil was carried out.

Concepts: Fat, Cyperus rotundus, Essential oil, Oil, Oils, Cyperus esculentus, Cyperus