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PubMed2005

[Allelopathy and chemical constituents of Ligularia virgaurea volatile].

Ligularia virgaurea is a noxious weed widely distributed on the psychro-grasslands of east Qinghai-Tibet Plateau of China, but the allelopathic effects of its volatile is less known. In this study, the allelopathy of L. virgaurea volatile to 5 kinds of grasses was examined, and its chemical constituents were analyzed by GC-MS. The results demonstrated that the volatile of growing L. virgaurea could inhibit the seed germination speed and germination rate of all tested grasses. The inhibitory effects on Elymus nutans and Bromus magnus were significant, while Poa annua and Festuca ovin were not very sensitive. 18 major constituents were identified from the essential oil of L. virgaurea, accounted for 68.24% of the total. The main chemical components were 2-methylheptane (9.84%), 3-methyl-heptane (8.25%), heptane (7.93%), 4-methyl-1-(methylethyl)-bicyclo [3, 1, 0] hex-2-ene (7.79%), 3-methyl-hexane (6.38%), 2-methyl-hexane (5.54%), and D-limonene (4.70%). Monoterpenoids accounted for 16.58% of the total, indicating that volatilization was one of the ways by which L. virgaurea released allelochemicals. The allelopathy of the volatile may play an important role in enhancing the competitive ability of the species, and be one of reasons of grassland degeneration.

Asteraceae↗
PubMed2005

[Study on extraction methods of volatile oil from Mosla soochowensis].

OBJECTIVE: To study the different extraction methods of the volatile oil from Mosla soochowensis Matsuda and to determine the optimum extraction method. METHODS: The yields and the chemical constituents of volatile oil were used to compare the different extraction methods including SFE-CO2, steam distillation and organic solvent (petroleum ether) extraction. RESULTS: The yield of volatile oil by means of SFE-CO2 was 3.46%, which was higher than others. The quality of the oil by means of SFE-CO2 and steam distillation was better. Based on the result of GC-MS, the constituents of volatile oil were similar. It was mainly the methyleugenol, accounted for about 42%. The second was monocyclic terpene, such as bornene, dihydrocarvon, carvacrol, accounted for about 27%. The third was sesqutierpenoids, such as nerolidene etc, accounted for about 19%. CONCLUSION: SFEE-CO2 is the optimum extraction method of the volatile oil from Mosla soochowensis Matsuda.

Carbon Dioxide↗
PubMed2006

[Effect of Huajiao volatile oil on Cu2+ -induced oxidative modification of low density lipoprotein in vitro].

OBJECTIVE: To evaluate the effect of Huajiao volatile oil on copper mediated low density lipoprotein (LDL) oxidative modification. METHODS: LDL was isolated by ultracenfugation from normal human plasma. The extent of LDL peroxidation was measured in terms of thiobarbituric acid reactive substances (TBARS) expressed as malondialdehyde (MDA) equivalents. The electrophoresis mobility of LDL was determined as relative electrophoresis mobility (REM) on an agarose gel electrophoresis. RESULTS: The TBARS generation and the REM in Cu2+ -induced oxidation of LDL with Huajiao volatile oil at different concentrations were statistically different (P < 0.01). The Cu2+ -induced oxidation of LDL without addition of Huajiao volatile oil exhibited a lag phase of 1 h, a rapid increasing phase at 2 h-4 h, and a summit phase starting at 24 h. Then, with the addition of Huajiao volatile oil (40 mg/mL), the lag phase lasted 4 h, the rapid increasing phase was seen at 6 h-8 h, but the summit of TBARS was not on the decline. CONCLUSION: Huajiao volatile oil could protect LDL against Cu2+ -induced oxidative modification in vitro.

Antioxidants↗
PubMed2005

[Extraction and determination of volatile constituents in leaves of Eucalyptus citriodora].

The volatile constituents in leaves of Eucalyptus citriodora, including oil fraction and water-soluble fraction, were extracted and determined. Oil fraction of volatile components was obtained through steam distillation. Ether was used as the solvent to extract the water-soluble fraction of volatile compounds from the liquid left after steam distillation in order to know the quantity and constituents of volatile compounds dissolved in the water phase. The oil yield in the oil fraction was 1.36%, and the oil yield in the water-soluble fraction was 0.48% (both on fresh weight basis). Both oil fraction and water-soluble fraction were analyzed by gas chromatography-mass spectrometry (GC-MS) method. The results showed that 37 compounds (97.36%) in the oil fraction and 10 compounds (82.05%) in the water-soluble fraction were identified. There were 12 hydrocarbon compounds and 25 oxygenated compounds identified in oil fraction. The major constituents in oil fraction were citronellal (57.00%), followed by citronellol (15.89%) and citronellyl acetate (15.33%). Alcohols dominated the compounds in water-soluble fraction. cis-p-Menthane-3, 8-diol (53.43%) and trans-p-menthane-3, 8-diol (16. 48%) were found to be the major compounds, which have the activity to repel insects. It is concluded that the comprehensive utilization value of leaves of Eucalyptus citriodora was enhanced owing to the extraction of water-soluble volatile components.

Acyclic Monoterpenes↗
PubMed2005

Repellency of volatile oils from Moschosma polystachyum and Solanum xanthocarpum against filarial vector Culex quinquefasciatus say.

Volatile oils extracted by steam distillation from leaves of two plant species Moschosma polystachyum and Solanum xanthocarpum were evaluated in mosquito cages for their topical repellency effects against filarial vector Culex quinquefasciatus. The oil from M. polystachyum was tested at four different concentrations ranging from 1 to 4%. The 4% concentration gave 332.2 minutes protection whereas control gave only 4.4 minutes protection against mosquito bites. However, the volatile oil of S.xanthocarpum was tested from 2 to 8% concentration. The 8% concentration gave 311.4 minutes protection whereas control gave only 4.4 minutes protection against mosquito bites. The results suggest that the volatile oils of these two plant species were effective as repellents and gave more than 300 minutes of (>5 hour) protection against the bite of Cx. quinquefasciatus bite. Both volatile oils did not cause dermal irritation when applied to human skin. No adverse effects on human volunteers were observed after application. Therefore, both volatile oils can be applied as an effective personal protection measure against mosquito bites.

Animals↗
PubMedDate not supplied

[Effect of carbon composition of the fermented medium on the synthesis of volatile acids by the yeast Saccharomyces carlsbergensis 776].

The effect of glucose, maltose and sucrose on the synthesis of volatile oils during fermentation of model carbohydrate solutions (6, 8 and 11%) by the yeast Saccharomyces carlsbergensis 776 was studied. The composition and concentration of carbohydrates affected the build-up of volatile fatty acids during fermentation. The accumulation of biomass and volatile fraction of fatty acids reached maximum on the medium containing 11% glucose. There was a certain correlation between the biomass synthesis and accumulation of volatile fatty acids, i.e. with an increase in the biomass the content of volatile fatty acids in the medium increased. During fermentation of disaccharide solutions cell multiplication diminished and the fermentation process accelerated. Ethanol, residual sugar and acidity of fermented solutions increased with the initial concentration of carbohydrates. The pH value of the fermented must remained essentially unaltered independent of the sugar amount used.

Culture Media↗
PubMed1980

[Influence of pH on the transfer of volatile fatty acids in the isolated cecal wall of the rat].

The influence of pH on the transfer of acetic, propionic and butyric acids was studied in vitro using everted sacs of the rat caecum. The sacs were filled with 2 ml of saline medium and then shaken 1 hr at 38 degrees C in flasks containing the same medium. A Krebs-Ringer phosphate incubation medium was used with O2 as gas phase. Incubation mediums containing 15 mM acetic, propionic and butyric acids were adjusted to give three different pH values: 7.91, 7.00 and 6.03. After incubation the mucosal and serosal fluids were collected and samples were taken to determine the pH and the volatile fatty acid concentrations. The pH values of mucosal and serosal fluids changed slightly during the course of the experiments. There was net volatile fatty acid influx into caecal tissue from the serosal medium and into the mucosal medium from the caecal tissue. Lowering the pH from 7.00 to 6.03 resulted in a significant decrease of serosal volatile fatty acid influxes. Caecal tissue retained more volatile fatty acids by lowering the pH from 7.91 to 7.00 and 6.03. Acetic acid accumulated in the caecal tissue against its electro-chemical gradient at pH 6.03. Two different mechanisms appeared to favor the transport of ionized and non-ionized forms of volatile fatty acids through the caecal membranes.

Acetates↗
PubMed2006

A variety of volatile compounds as markers in unifloral honey from dalmatian sage (Salvia officinalis L.).

Volatile compounds of unifloral Salvia officinalis L. honey has been investigated for the first time. The botanical origin of ten unifloral Salvia honey samples has been ascertained by pollen analysis (the honey samples displayed 23-60% of Salvia pollen). Fifty-four volatile compounds were identified by GC and GC/MS in ten Salvia honey extracts obtained by ultrasound-assisted extraction (USE) with pentane/Et(2)O 1 : 2. The yield of isolated volatiles varied from 25.7 to 30.5 mg kg(-1). Salvia honey could be distinguished on the basis of the high percentage of benzoic acid (6.4-14.8%), and especially phenylacetic acid (5.7-18.4%). Minor, but floral-origin important volatiles were identified such as shikimate pathway derivatives, 'degraded-carotenoid-like' structures (3,5,5-trimethylcyclohex-2-ene derivatives) and 2,6,6-trimethylcyclohex-2-ene derivatives. Compounds from other metabolic pathways such as aliphatic acids and higher linear hydrocarbons, as well as heterocycles (pyrans, furans, and pyrroles), were also present. Most of the identified compounds do not constitute specific Salvia honey markers, due to their presence in honeys of other botanical origins; however, their ratio in different honeys could be useful to distinguish floral origin. Salvia-honey volatile markers were: benzoic acid, phenylacetic acid, p-anisaldehyde, alpha-isophorone, 4-ketoisophorone, dehydrovomifoliol, 2,6,6-trimethyl-4-oxocyclohex-2-ene-1-carbaldehyde, 2,2,6-trimethylcyclohexane-1,4-dione, and coumaran.

Chemistry↗
PubMed1975

[About the formation of volatile products during lipoxigenase-linoleic-acid reaction (author's transl)].

Soya-lipoxigenase (E.C. 1.13.1.13) is incubated by linoleic acid at room temperature; the arising volatile products are isolated by different methods, concentrated, and investigated by means of gas chromatography. If the non-volatile hydroperoxides, formed during the incubation are also injected, 15-20% are decomposed to volatile products superposing the primarily enzymatically formed volatile components as artefacts and consequently falsifying the result. Without separating the linoleic acid hydroperoxides (LHPO) the quantitative proportion Hexanal/Decadienal is approximately in accordance with the proportion 13-linoleic acid hydroperoxide/9-linoleic acid hydroperoxide (this means for soya-lipoxigenase and pH 7 about 1:1). After separating the linoleic acid hydroperoxides only these volatile products are found which are arising during the lipoxigenase reaction. These are 1-2% in relation to the LHPO. In this case, the quantitative ratio Hexanal/Decadienal is not corresponding to the 13-/9-linoleic acid hydroperoxide proportion. Nearly the only product formed by this process is Hexanal.

Chromatography, Gas↗
PubMed1975

Failure to demonstrate degradation of (4-14C) cholesterol to volatile hydrocarbons in rats and in human fecal homogenates.

The inability of previous workers to recover completely the radioactivity from ingested [4-14C] cholesterol has led to the hypothesis that the colonic flora of some individuals degrade the sterol nucleus to volatile hydrocarbons, particularly CH4. In the present investigation, the production of radioactive volatiles was measured following incubation of [4-14C] cholesterol with 8 human fecal homogenates or after instillation of the labeled sterol into the cecum of 3 rats housed in a closed rebreathing system. Three of the 8 homogenates and each of the 3 rats produced copious CH4. However, analysis by combustion demonstrated no radioactivity above background in the volatile headspace of the homogenates or the gas space of the closed system housing the rats, indicating that less than 0.001% of the number 4 carbon of [4-14C] cholesterol could have been converted to volatile hydrocarbons. This study, therefore, provides no support for the concept that volatile products account for the incomplete recovery of ingested sterols observed in certain subjects. However, this hypothesis can not be excluded entirely until similar results are obtained with subjects who can be shown to degrade cholesterol.

Animals↗
PubMed1989

Effect of alpha-tocopherol on the volatile thermal decomposition products of methyl linoleate hydroperoxides.

alpha-Tocopherol and 1,4-cyclohexadiene were tested for their effect on the thermal decomposition of methyl linoleate hydroperoxide isomers. The volatiles generated by thermolysis in the injector port of a gas chromatograph at 180 degrees C were analyzed by capillary gas chromatography. In the presence of either alpha-tocopherol or 1,4-cyclohexadiene, which are effective donors of hydrogen by radical abstraction, volatile formation decreased in all tests, and significant shifts were observed in the relative distribution of products in certain hydroperoxide samples. When an isomeric mixture of methyl linoleate hydroperoxides (cis, trans, and trans,trans 9- and 13-hydroperoxides) was decomposed by heat, the presence of alpha-tocopherol and 1,4-cyclohexadiene caused the relative amounts of pentane and methyl octanoate to decrease and hexanal and methyl 19-oxononanoate to increase. A similar effect of alpha-tocopherol was observed on the distribution of volatiles formed from a mixture of the trans,trans 9- and 13-hydroperoxides. This effect of alpha-tocopherol was, however, insignificant with pure cis,trans 13-hydroperoxide of methyl linoleate. The decrease in total volatiles with the hydrogen donor compounds, alpha-tocopherol and 1,4-cyclohexadiene, indicates a suppression of homolytic beta-scission of the hydroperoxides, resulting in a change in relative distribution of volatiles. The increase in hexanal and methyl 9-oxononanoate at the expense of pentane and methyl octanoate in the presence of hydrogen donor compounds supports the presence of a heat-catalyzed heterolytic cleavage (also known as Hock cleavage), which seems to mainly affect the trans,trans isomers of linoleate hydroperoxides.

Antioxidants↗
PubMed2003

The influence of volatile anesthetics on alveolar epithelial permeability measured by noninvasive radionuclide lung scan.

Many volatile anesthetics have long been thought to affect pulmonary functions including lung ventilation (LV) and alveolar epithelial permeability (AEP). The purpose of this study is to examine the influence of volatile anesthetics on LV and AEP by noninvasive radionuclide lung imaging of technetium-99m labeled diethylene triamine pentaacetic acid radioaerosol inhalation lung scan (DTPA lung scan). Twenty patients undergoing surgery and receiving volatile anesthesia with 1% halothane were enrolled as the study group 1. The other 20 patients undergoing surgery and receiving volatile anesthesia with 1.5% isoflurane were enrolled as the study group 2. At the same time, 20 patients undergoing surgery with intravenous anesthesia drugs were included as a control group. Before surgery, 1 hour after surgery, and 1 week after surgery, we investigated the 3 groups of patients with DTPA lung scan to evaluate LV and AEP by 99mTc DTPA clearance halftime (T1/2). No significant change or abnormality of LV before surgery, 1 hour after surgery, or 1 week after surgery was found among the 3 groups of patients. In the control group, the 99mTc DTPA clearance T1/2 was 63.5 +/- 16.4, 63.1 +/- 18.4, and 62.8 +/- 17.0 minutes, before surgery, 1 hour after surgery, and 1 week after surgery, respectively. In group 1, it was 65.9 +/- 9.3, 62.5 +/- 9.1, and 65.8 +/- 10.3 minutes, respectively. No significant change in AEP before surgery, 1 hour after surgery, or 1 week after surgery was found. However, in group 2, the 99mTc DTPA clearance T1/2 was 65.5 +/- 13.2, 44.9 +/- 10.5, and 66.1 +/- 14.0 minutes, respectively. A significant transient change in AEP was found 1 hour after surgery, but it recovered 1 week after surgery. We conclude that volatile anesthesia is safe for LV and AEP, and only isoflurane can induce transient change of AEP.

Administration, Inhalation↗
PubMed2006

The effects of volatile anesthetics on cardiac ischemic complications and mortality in CABG: a meta-analysis.

PURPOSE: Coronary artery bypass graft surgery (CABG) is associated with cardiac complications, including ischemia, acute myocardial infarction (AMI), and death. Volatile anesthetics have been shown to have a preconditioning-like effect. This systematic review assesses the effects of volatile anesthetics on cardiac ischemic complications and morbidity after CABG. METHODS: Data were obtained, without language restriction, from searches of MEDLINE, Science Citation Index, PubMed, and reference lists. We included only prospective randomized controlled trials evaluating volatile anesthetics during CABG. Two reviewers independently abstracted data on myocardial ischemia, acute myocardial infarction (AMI), and death. Treatment effects were calculated as odds ratio (OR) with 95% confidence intervals (CI) for binary data, and weighted mean difference (WMD) with 95% CI for continuous data. PRINCIPAL FINDINGS: Thirty-two studies (2,841 patients) were included. In comparison with iv anesthesia, volatile anesthetics were associated with reduced all-cause mortality (OR, 0.65; 95% CI, 0.36-1.18; P = 0.16). Enflurane was associated with increased AMI (OR, 1.34; 95% CI, 0.68-2.64; P = 0.40), whereas sevoflurane and desflurane reduced cardiac troponin I (cTnI) at six hours, 12 hr, 24 hr [WMD, -1.45; 95% CI (-1.73, -1.16); P < 0.00001], and 48 hr after operation. CONCLUSION: This meta-analysis demonstrates sevoflurane and desflurane reduce the postoperative rise in cTnI. Sevoflurane-mediated reduction in cardiac troponin was associated with improved long-term outcomes in one study. This meta-analysis was not able to show that these positive effects on troponin were translated into improved clinical outcomes. Well-designed large randomized control trials are needed to further elucidate the differential cardio-protective effects of volatile anesthetics.

Anesthetics, Inhalation↗
PubMed1983

A volatile inhibitor immobilizes sea urchin sperm in semen by depressing the intracellular pH.

Sea urchin spermatozoa are normally immotile in semen, but motility can be initiated by increasing gas flow over the semen--for example, by blowing N2 gas over a thin layer of semen. This result indicates that sperm motility is not O2 limited and suggests that seminal fluid contains a volatile inhibitor of motility which is responsible for the paralysis of sperm in semen. This inhibitor might be carbon dioxide, which reversibly immobilizes sperm. 31P-NMR measurements of pH show that the sperm intracellular pH (pHi) increases by 0.36 pH unit upon dilution of semen into seawater. Since previous studies have shown that this magnitude of pH increase is sufficient to trigger sperm motility, we suggest that the volatile inhibitor is inhibiting sperm motility in semen by depressing the pHi. A simple hypothesis that explains these observations is that the volatile motility inhibitor is CO2, which could acidify pHi as a diffusable weak acid. In this regard, sperm diluted into seawater release acid, and this acid release is related to the pHi increase and motility initiation. In fact, nearly half of the acid released by sperm upon dilution is volatile and may therefore be due to CO2 efflux. Most of the acid, however, cannot be attributed to CO2 release because it is not volatile. Thus, when sperm are diluted into seawater, they raise their pHi by releasing CO2 and protons from the cytoplasm into the surrounding seawater.

Animals↗
PubMedDate not supplied

Relaxant effect of the volatile oil of Rosmarinus officinalis on tracheal smooth muscle.

The effects of the volatile oil of Rosmarinus officinalis leaves on the tracheal smooth muscle of rabbit and guinea pig were tested in vitro using isolated tracheal strips. The volatile oil of R. officinalis leaves inhibited the contractions of rabbit tracheal smooth muscle induced by acetylcholine stimulation and the contractions of guinea pig tracheal smooth muscle induced by histamine stimulation. Also, the volatile oil inhibited the contractions of rabbit and guinea pig tracheal smooth muscle induced by high potassium (K+) solution. This inhibition was dose-dependent and reversible. Furthermore, the volatile oil inhibited the contractions of rabbit and guinea pig tracheal smooth muscle induced by acetylcholine and histamine stimulation, respectively, in Ca(2+)-free solution. These data suggest that the volatile oil of R. officinalis leaves has a calcium antagonistic property.

Acetylcholine↗
PubMed2006

Mitochondrial complex I function modulates volatile anesthetic sensitivity in C. elegans.

Despite the widespread clinical use of volatile anesthetics, their mechanisms of action remain unknown [1-6]. An unbiased genetic screen in the nematode C. elegans for animals with altered volatile anesthetic sensitivity identified a mutant in a nuclear-encoded subunit of mitochondrial complex I [7,8]. This raised the question of whether mitochondrial dysfunction might be the primary mechanism by which volatile anesthetics act, rather than an untoward secondary effect [9,10]. We report here analysis of additional C. elegans mutations in orthologs of human genes that contribute to the formation of complex I, complex II, complex III, and coenzyme Q [11-14]. To further characterize the specific contribution of complex I, we generated four hypomorphic C. elegans mutants encoding different complex I subunits [15]. Our main finding is the identification of a clear correlation between complex I-dependent oxidative phosphorylation capacity and volatile anesthetic sensitivity. These extended data link a physiologic determinant of anesthetic action in a tractable animal model to similar clinical observations in children with mitochondrial myopathies [16]. This work is the first to specifically implicate complex I-dependent oxidative phosphorylation function as a primary mediator of volatile anesthetic effect.

Anesthetics↗
PubMed2004

Electroantennogram responses of the three migratory forms of the damson-hop aphid, Phorodon humuli, to aphid pheromones and plant volatiles.

Electroantennogram (EAG) responses were recorded from alate fundatrigeniae (spring migrants), gynoparae (the winged female form that produces sexual females) and males, the three migratory forms of the damson-hop aphid, Phorodon humuli (Schrank). EAG responses of gynoparae and males showed typical dose response characteristics to (E)-2-hexenal, (-)-R-carvone, hexanenitrile and (1RS,4aR,7S,7aS)-nepetalactol, the sex pheromone of this species. The 34 plant volatiles elicited broadly similar EAG response profiles in the three migratory forms. Green leaf volatiles produced large responses in all forms; however, the relative order of responsiveness varied. EAG responses to isomers of the monoterpene carvone differed between forms, with males being most, and spring migrants least, responsive. The hop-plant volatile and aphid alarm pheromone, (E)-beta-farnesene, evoked similar EAG responses in all forms. By contrast, males were most responsive to the three sex pheromone components, (-)-(4aS,7S,7aR)-nepetalactol, (+)-(4aS,7S,7aR)-nepetalactone and (1RS,4aR,7S,7aS)-nepetalactol. Males were no more responsive to their own sex pheromone, (1RS,4aR,7S,7aS)-nepetalactol, than to the other aphid sex pheromone components tested. Spring migrants and gynoparae also responded to the three sex pheromone components. This study indicates that migratory forms of P. humuli detect a wide range of volatile compounds, and that they are equally well-adapted for the detection of volatiles associated with host and non-host plants and with other species of aphid.

Animal Migration↗
PubMed2006

Sex steroids modulate the signals from volatile female odors in the accessory olfactory bulb of male mice.

We previously reported that male mice detect volatile female odors via the accessory olfactory system, and that these odors activate granule cells in the accessory olfactory bulb (AOB) with a characteristic pattern. We also reported that sex steroids modulate the attraction of male mice to volatile female odors. The present study investigated hormonal modulation of signals from volatile female odors in the AOB with c-Fos immunostaining. After intact male mice were exposed to volatile female odors, there were more c-Fos positive cells in the caudal granule cell layer (GCL) than in the rostral GCL of the AOB. This effect was observed 3 days but not 7 days after castration, suggesting that hormonal deficiency causes the reorganization of the AOB after 3 days. There was no difference in the number of c-Fos positive cells between the rostral and caudal GCL of castrated male mice treated with 17 beta-estradiol (E). In contrast, there were more c-Fos positive cells in the caudal GCL than in the rostral GCL of castrated male mice treated with dihydrotestosterone (DHT). In both DHT- and E-treated castrated male mice, there was no difference in the number of c-Fos positive cells between the rostral GCL and caudal GCL. This finding suggests that E disrupts the effect of DHT, and that androgen is required for maintaining the intact neuronal network of the AOB. The present study suggests that sex steroids modulate the signals from volatile female odors in the AOB of male mice.

Androgens↗