Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Oils, Volatile”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources
PubMed1991

Chemical, physiological, and toxicological aspects of the essential oil of some species of the genus Bystropogon.

The composition of the essential oils of Bystropogon plumosus, B. origanifolius var. palmensis, B. wildpretii, B. maderensis, and B. canariensis var. smithianus were studied by GLC and GLC/MS. The first four species provide relatively similar oils characterized by monoterpene ketones as the main constituents while the last species is quite different with main constituents consisting of mono- and sesquiterpene hydrocarbons. In B. plumosus the ontogenetic variation of the monoterpene ketones was studied for a period of four years. During this time the behaviour of pulegone was inversely correlated with that of menthone and isomenthone. Pulegone was the most active compound of the monoterpene ketones in antimicrobial tests using three species of bacteria and fungi, respectively.

Anti-Bacterial Agents↗
PubMed1989

Teratological evaluation of Juniperus sabina essential oil in mice.

Juniperus sabina essential oil was evaluated for its fetotoxic potential on mice. Pregnant dams were injected s.c. (15-45 or 135 mg essential oil/kg body weight) on days 6 to 15 of gestation. They were killed and the uterine contents were examined on day 19 of pregnancy. The fetuses were removed for examination. The dams of the two higher treated groups showed a significant weight loss as compared to controls. An hepatotoxicity was observed among females that resorbed their whole litter, thus indicating a greater susceptibility towards Juniperus sabina essential oil during pregnancy. The essential oil induced, in the three treated groups, an embryotoxicity as manifested by a statistically significant increase in the number of affected litters; but no fetotoxicity.

Animals↗
PubMed1993

Caraway oil inhibits skin tumors in female BALB/c mice.

Caraway oil, supplemented in diet or painted on the skin, inhibited 7,12-dimethylbenz[a]anthracene- (DMBA) and croton oil-induced skin tumors in female BALB/c mice. The inhibition was manifested by disappearance of carcinomas, reduced incidence and number of papillomas, delay of their appearance, retardation of their development, and regression of already established papillomas. Caraway oil is more effective when topically applied than when supplemented in the diet.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2004

Olfactory discrimination and transient mood change in young men and women: variation by season, mood state, and time of day.

Odor performance varies by clinical state and gender, though little is known about its variation by season or time of day. Many odors, including lavender, induce transient mood changes. This study explored discrimination differences between various lavender oil blends and their effects on transient mood in the morning and evening in depressed and nondepressed adults. We also determined seasonal influences on these measures. A total of 169 subjects, 98 women and 71 men (mean age +/- SD, 19.3 +/- 1.6 y) participated, with different subjects studied at different times of the year. The Beck Depression Inventory (BDI) classified subjects as depressed (score > or =10; N= 57) or nondepressed (score <10; N= 112). In the discrimination test, subjects compared pairs of two different lavender oil blends or a control. Transient change in mood was assessed by the Profile of Mood States (POMS) after each trial of five lavender blends interspersed by three control odors. Tests were conducted in the morning (08:00-10:00 h) and evening (18:00-20:00h). In all subjects, discrimination was significantly better for some odor pairs than for others, thus demonstrating test specificity. Discrimination was better overall in the fall than winter/spring and better in depressed than nondepressed subjects for specific odor pairs. No significant gender or time-of-day differences in discriminability were detected. There were, however, significant group differences in transient mood profiles. Current depressed state affected mood response, with lavender increasing anger in depressed subjects only. In addition, depressed subjects and men, whether or not depressed, exhibited diurnal mood variation, with better mood in the evening; the former group also showed more evening energy. All subjects were more confused in the morning than evening. Season also affected transient mood; winter/spring-tested subjects reported more vigor than fall-tested subjects. In addition, summer-tested subjects showed more tension in the morning, whereas fall-tested subjects showed the opposite pattern in the evening. In all subjects, lavender increased fatigue, tension, confusion, and total mood disturbance, and it decreased vigor. The study showed that both chronobiological (seasonal and time-of-day) and clinical factors modify discrimination and mood response to odors. Brief lavender odor presentation may serve as a nonphotic method for altering mood in young depressed and nondepressed adults particularly during the fall, a time of heightened discriminability.

Adolescent↗
PubMed2004

Importance of learning in the response of ewes to male odor.

Exposure of anestrous ewes to a ram or its odor results in the activation of the luteinizing hormone (LH) secretion leading to reinstatement of cyclicity in most females. Sexual experience and learning have been suggested as important factors to explain the variability of the female responses. In experiment 1, we compared the behavioral and endocrine responses of four groups of anestrous females that differed in age (young or adult) and previous exposure to males [naive (no exposure) or experienced (courtship behavior for young and numerous mating for adults)]. Age did not seem to affect the LH response to males or their odor. In contrast, sexual experience was a critical factor: the proportion of females exhibiting an LH response to male odor was significantly higher in experienced than in naive ewes. Sexual experience affected the response to male odor, but did not have an effect on responses to the male himself. A second experiment investigated whether the LH response to male odor could result from an associative learning process. Accordingly, we tested the effectiveness of a conditioned stimulus (lavender odor) previously associated with the male, in inducing the endocrine response. The results indicate that the odor of lavender activated LH secretion only in ewes that have been previously exposed to scented males. This demonstrates that ewes are able to learn the association between a neutral odor and their sexual partner.

Aging↗
PubMed1995

Susceptibility of methicillin-resistant Staphylococcus aureus to the essential oil of Melaleuca alternifolia.

All 66 isolates of Staphylococcus aureus tested were susceptible to the essential oil of Melaleuca alternifolia, or tea tree oil, in disc diffusion and modified broth microdilution methods. Of the isolates tested, 64 were methicillin-resistant S. aureus (MRSA) and 33 were mupirocin-resistant. The MIC and MBC for 60 Australian isolates were 0.25% and 0.50%, respectively. Comparable results were obtained by co-workers in Britain using similar methods. These in-vitro results suggest tea tree oil may be useful in the treatment of MRSA carriage.

Methicillin Resistance↗
PubMed1998

In-vitro activity of essential oils, in particular Melaleuca alternifolia (tea tree) oil and tea tree oil products, against Candida spp.

The in-vitro activity of a range of essential oils, including tea tree oil, against the yeast candida was examined. Of the 24 essential oils tested by the agar dilution method against Candida albicans ATCC 10231, three did not inhibit C. albicans at the highest concentration tested, which was 2.0% (v/v) oil. Sandalwood oil had the lowest MIC, inhibiting C. albicans at 0.06%. Melaleuca alternifolia (tea tree) oil was investigated for activity against 81 C. albicans isolates and 33 non-albicans Candida isolates. By the broth microdilution method, the minimum concentration of oil inhibiting 90% of isolates for both C. albicans and non-albicans Candida species was 0.25% (v/v). The minimum concentration of oil killing 90% of isolates was 0.25% for C. albicans and 0.5% for non-albicans Candida species. Fifty-seven Candida isolates were tested for sensitivity to tea tree oil by the agar dilution method; the minimum concentration of oil inhibiting 90% of isolates was 0.5%. Tests on three intra-vaginal tea tree oil products showed these products to have MICs and minimum fungicidal concentrations comparable to those of non-formulated tea tree oil, indicating that the tea tree oil contained in these products has retained its anticandidal activity. These data indicate that some essential oils are active against Candida spp., suggesting that they may be useful in the topical treatment of superficial candida infections.

Antifungal Agents↗
PubMed2004

Toxicity of plant essential oils to Tetranychus urticae (Acari: Tetranychidae) and Phytoseiulus persimilis (Acari: Phytoseiidae).

Fifty-three plant essential oils were tested for their toxicity against eggs and adults of Tetranychus urticae Koch as well as adults of Phytoseiulus persimilis Athias-Henriot, by using a filter paper diffusion bioassay without allowing direct contact. Responses varied according to oil type and dose, and mite species. In a plastic container (4.5 by 9.5 cm) bioassay at 14 x 10(-3) microl/ml air, caraway seed, citronella java, lemon eucalyptus, pennyroyal, and peppermint oils gave > 90% mortality against adult T. urticae, whereas 82 and 81% mortality was observed with sage and spearmint oils, respectively. With the exception of sage oil, the other six essential oils were highly effective against T. urticae eggs at 9.3 x 10(-3) microl/ml air. Against adult P. persimilis, these six test oils caused > 90% mortality at 7.1 x 10(-3) microl/ml air. Particularly peppermint oil at 4.7 x 10(-3) microl/ml air was highly toxic. In an acrylic cage (30 by 30 by 40 cm ) test, lemon eucalyptus, pennyroyal, peppermint, and spearmint oils were highly effective against adult T. urticae at 1.4 x 10(-3) microl/ml air. These results indicate that the mode of delivery of these essential oils was largely a result of action in the vapor phase via the respiratory system. The essential oils described herein merit further study as potential fumigants for T. urticae control.

Animals↗
PubMed2004

Repellency of ginger oil to Bemisia argentifolii (Homoptera: Aleyrodidae) on tomato.

The whitefly Bemisia argentifolii Bellows & Perring is an economically important pest of tomatoes, Lycopersicon esculentum Mill., inducing an irregular ripening disorder of fruit and transmitting plant pathogenic viruses. With the goal of investigating ginger oil as a protectant for tomato plants, we tested the effects of concentration of ginger oil and application methods on repellency to whitefly in a vertical still-air olfactometer. In choice and no-choice experiments conducted in a greenhouse, we evaluated whether ginger oil would protect tomato seedlings from whitefly settling and oviposition. Ginger oil repelled whitefly adults in the vertical olfactometer. The repellency of ginger oil was attributed to its odor, effective at the concentrations used over a distance of 1-2 mm. Tomato leaf disks dipped in ginger oil repelled whiteflies at concentrations of 0.5, 0.75, and 1%, but not at concentrations <0.5%, in a dose-response experiment conducted in the olfactometer. Repellency increased with increasing ginger oil concentration when leaf disks were dipped in ginger oil but not when ginger oil was sprayed onto the leaf disks. Higher quantities of monoterpenes and sesquiterpenes were deposited on leaf disks dipped in ginger oil than on sprayed leaf disks according to gas chromatographic quantification. In the greenhouse, both choice and no-choice tests were conducted with tomato seedlings dipped in 0.25% ginger oil solution or 2% Tween 20, as treatment and control, respectively. In the choice test, 35-42% fewer whitefly adults settled and 37% fewer eggs were laid during the 24-h exposure period on tomato plants dipped in ginger oil solution than on plants dipped in 2% Tween 20. In the no-choice test, 10.2-16.7% fewer whiteflies settled on treated plants compared with control plants but no significant differences were detected in the number of eggs laid. Higher concentrations of ginger oil could not be used without causing severe wilting of tomato leaves. Ginger oil has potential as a protectant of tomato seedlings against B. argentifolii, but issues of phytotoxicity and coverage need to be addressed.

Animals↗
PubMed2005

Use of novel compounds for pest control: insecticidal and acaricidal activity of essential oil components from heartwood of Alaska yellow cedar.

Laboratory bioassays were conducted to determine the activity of 15 natural products isolated from essential oil components extracted from the heartwood of Alaska yellow cedar, Chamaecyparis nootkatensis (D. Don) Spach., against Ixodes scapularis Say nymphs, Xenopsylla cheopis (Rothchild), and Aedes aegypti (L.) adults. Four of the compounds from the essential oil have been identified as monoterpenes, five as eremophilane sesquiterpenes, five as eremophilane sesquiterpene derivatives from valencene and nootkatone, and one as a sesquiterpene outside the eremophilane parent group. Carvacrol was the only monoterpene that demonstrated biocidal activity against ticks, fleas, and mosquitoes with LC50 values after 24 h of 0.0068, 0.0059, and 0.0051% (wt:vol), respectively. Nootkatone from Alaska yellow cedar was the most effective of the eremophilane sesquiterpenes against ticks (LC50 = 0.0029%), whereas the nootkatone grapefruit extract exhibited the greatest biocidal activity against fleas (LC50 = 0.0029%). Mosquitoes were most susceptible to one of the derivatives of valencene, valencene-13-aldehyde (LC50 = 0.0024%), after 24 h. Bioassays to determine residual activity of the most effective products were conducted at 1, 2, 4, and 6 wk after initial treatment. Residual LC50 values for nootkatone did not differ significantly at 4 wk posttreatment from the observations made at the initial 24-h treatment. The ability of these natural products to kill arthropods at relatively low concentrations represents an alternative to the use of synthetic pesticides for control of disease vectors.

Aedes↗
PubMed2002

(1S,3R,8S,9S,10R)-2,2-Dichloro-9,10-epoxy-3,7,7,10-tetramethyltricyclo[6.4.0.0(1,3)]dodecane and (1S,3R,8S,10R)-2,2-dichloro-3,7,7,10-tetramethyltricyclo[6.4.0.0(1,3)]dodecan-9-one.

The stereochemistries of the title compounds, both C(16)H(24)Cl(2)O, have been established by X-ray diffraction. In both structures, the seven-membered ring adopts the same conformation, whereas the six-membered ring shows an envelope conformation in the epoxydodecane structure and a boat conformation in the dodecan-9-one structure.

Bridged-Ring Compounds↗
PubMed2004

Cytotoxicity of lavender oil and its major components to human skin cells.

Lavender (Lavandula angustifolia) oil, chiefly composed of linalyl acetate (51%) and linalool (35%), is considered to be one of the mildest of known plant essential oils and has a history in wound healing. Concerns are building about the potential for irritant or allergenic skin reactions with the use of lavender oil. This study has demonstrated that lavender oil is cytotoxic to human skin cells in vitro (endothelial cells and fibroblasts) at a concentration of 0.25% (v/v) in all cell types tested (HMEC-1, HNDF and 153BR). The major components of the oil, linalyl acetate and linalool, were also assayed under similar conditions for their cytotoxicity. The activity of linalool reflected that of the whole oil, indicating that linalool may be the active component of lavender oil. Linalyl acetate cytotoxicity was higher than that of the oil itself, suggesting suppression of its activity by an unknown factor in the oil. Membrane damage is proposed as the possible mechanism of action.

Acyclic Monoterpenes↗
PubMed1995

Antimicrobial activity of the major components of the essential oil of Melaleuca alternifolia.

Tea tree oil, or the essential oil of Melaleuca alternifolia, is becoming increasingly popular as a naturally occurring antimicrobial agent. The antimicrobial activity of eight components of tea tree oil was evaluated using disc diffusion and broth microdilution methods. Attempts were also made to overcome methodological problems encountered with testing compounds which have limited solubility in aqueous media. After assessing media with and without solubilizing agents, the disc diffusion method was used to determine the susceptibility of a range of micro-organisms to 1,8-cineole, 1-terpinen-4-ol, rho-cymene, linalool, alpha-terpinene, gamma-terpinene, alpha-terpineol and terpinolene. While the disc diffusion method lacked reproducibility, it was considered useful as a procedure for screening for antimicrobial activity. Terpinen-4-ol was active against all the test organisms while rho-cymene demonstrated no antimicrobial activity. Linalool and alpha-terpineol were active against all organisms with the exception of Pseudomonas aeruginosa. Minimum inhibitory and minimum cidal concentrations of each component against Candida albicans, Escherichia coli and Staphylococcus aureus were determined using a broth microdilution method. Modifications to this method overcame solubility and turbidity problems associated with the oil components and allowed the antimicrobial activity of each of the components to be quantified reproducibly. There was reasonable agreement between minimum inhibitory concentrations and zones of inhibition. These results may have significant implications for the future development of tea tree oil as an antimicrobial agent.

Anti-Infective Agents, Local↗