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PubMed2004

[Study on preparation of beta-cyclodextrin inclusion volatile oil from Rhizoma Curcumae].

OBJECTIVE: To study optimum inclusion process conditions for volatile oil from Rhizoma Curcumae. METHOD: The study was carried out with orthogonal design. The process conditions were studied by determining the utilazision ratio of volatile oil from Rhizoma Curcumae, the oil-bearing rate and extract ratio of inclusion compound. RESULTS: The optimum preparation conditions for inclusion were established as: volatile oil:beta-CD was 1:8, the inclusion temperature was at 80 degrees C and inclusion time for 3 h, ultilizasion rate of volatile oil was 86%. CONCLUSION: The method can be used for mass production.

Curcuma↗
PubMed2005

[Chemical components of volatiles form withered black poplar leaves with different physiological age].

By the methods of steam distillation and GC-MS, this paper analyzed the chemical components of the volatiles from withered black poplar leaves. The main components of the volatiles from young leaves were(Z)-3-hexenol (44.81% ),4-methyl-1-pentanol (21.85%) and 2-hydroxy-benzaldehyde (15.19%), those from matured leaves were(Z)-3-hexenol (28.71%) and 2-hydroxy-benzaldehyde (10.35%), while in the volatiles from senescent leaves, the main components were 2-hydroxy-benzaldehyde (28.81%) and benzyl alcohol (15.06%). The (Z)-3-hexenol content in the volatiles was evidently decreased with increasing leaf age, while the species and contents of aromatic compounds were in adverse.

Benzyl Alcohol↗
PubMed2005

Chemical composition and anti-mosquito potential of rhizome extract and volatile oil derived from Curcuma aromatica against Aedes aegypti (Diptera: Culicidae).

Crude rhizome extracts and volatile oils of Curcuma aromatica were evaluated for chemical composition and anti-mosquito potential, including larvicidal, adulticidal, and repellent activities against the Aedes aegypti mosquito. Chemical identification achieved by GC/MS analysis revealed that xanthorrhizol, 1H-3a, 7-methanoazulene and curcumene at 35.08 and 13.65%, 21.81 and 30.02%, and 13.75 and 25.71%, were the main constituents in hexane extracts and volatile oils, respectively. Volatile oil of Cu. aromatica possessed a significantly higher larvicidal activity against the 4th instar larvae of Ae. aegypti than that of hexane extracts, with LC50 values of 36.30 and 57.15 ppm, respectively. In testing for adulticidal activity, on the other hand, hexane-extracted Cu. aromatica (LC50: 1.60 microg/mg female) was found to be slightly more effective against female Ae. aegypti than volatile oil (LC50: 2.86 microg/mg female). However, the repellency of these two products against Ae. aegypti adult females differed significantly. The hexane-extracted Cu. aromatica, with a median complete protection time of 1 h (range = 1-1.5 h) when applied at a concentration of 25%, appeared to have significantly higher repellency than that of distillate oil (0.5 h, range = 0-0.5 h). The different results obtained from both products of Cu. aromatica were probably due to variety in quantity and type of active ingredients as well as the biological and physiological characteristics that differed between both developmental stages of mosquitoes, larvae, and adults.

Adolescent↗
PubMed1991

Effects of several volatile anesthetics on the Ca(2+)-related functions of skinned skeletal muscle fibers from the guinea pig.

The effects of various volatile anesthetics on intramuscular Ca(2+)-related functions were studied with the skinned fiber technique in guinea pig skeletal muscles. All the volatile anesthetics tested significantly enhanced Ca(2+)-induced Ca2+ release (CICR) from the sarcoplasmic reticulum (SR) at clinical concentrations with negligible effects both on Ca2+ sensitivity of the contractile system and on Ca2+ uptake by the SR. A comparison was made of the enhancing effect of several volatile anesthetics on CICR at clinical concentrations. Halothane was the most potent, followed by methoxyflurane, isoflurane, enflurane, sevoflurane and diethyl ether. If CICR plays an important role in triggering MH, this order of volatile anesthetics on their enhancing effect on CICR, also corresponds to their potency in triggering MH.

Anesthetics↗
PubMed1990

Buffer solutes as stabilizers of 35S-amino acids: a study of volatility, radiochemical purity and biological activity.

It is well established that volatile radioactive compounds are associated with preparations of 35S-amino acids, but misconceptions still exist. The addition of stabilizers to these preparations has created a false sense of security regarding the evolution of these volatiles from cell culture medium. Experiments presented here show that the commercially used buffers L-lysine, tricine and 3,4-pyridine-dicarboxylic acid all reduced, but did not eliminate, the evolution of 35S volatiles from tissue culture medium. In each case, the rate of release was approximately 12 nCi/mCi/day (or 0.001%), compared to approximately 44 nCi/mCi/day in the buffer's absence. None of six alternative buffers tested are more effective than the commercially used buffers. We found that the release of labeled volatiles is dependent on the nature of the culture medium, but is no greater from crude 35S-amino acid preparations than from purified 35S-methionine. These commercially used buffers are also effective in maintaining radiochemical purity and are compatible with biological activity; however, because these buffers do not entirely eliminate the release of radioactivity into the gas phase, routine safe-handling procedures should be practiced when working with these products.

Amino Acids↗
PubMed1977

Direct analysis of volatile organic compounds produced by fungi.

A gas chromatographic head-space technique has been developed for the analysis of volatile organic compounds produced by fungi. The method described is useful for establishing the pattern of volatile compounds emitted by an organism and for following the time course of production of volatile metabolites. Many of these volatile products are physiologically active and influence the growth and development of the same or other organisms.

Alcohols↗
PubMed1987

Protein origin of the volatile fatty acids isobutyrate and isovalerate in human stool.

Normal human stool contains five commonly recognized volatile fatty acids, of which three (acetate, propionate, and butyrate) are the product of carbohydrate degradation. We investigated whether the remaining two volatile fatty acids, isobutyrate and isovalerate, are produced by degradation of amino acids. Stools from six healthy subjects were incubated with albumin, valine, leucine, tryptophan, phenylalanine, glucose, or sucrose under atmospheres containing oxygen in the range of 0% to 5%. Isobutyrate was produced only from albumin and valine, and isovalerate was produced only from albumin and leucine. Glucose- and sucrose-containing incubates produced only acetate, propionate, and butyrate. The rate of production for each of the volatile fatty acids was constant over the various oxygen concentrations tested. We conclude that isobutyrate and isovalerate in stool are formed from valine and leucine degradation respectively. Quantitation of individual fecal volatile fatty acid excretions may reflect intracolonic degradation of protein and carbohydrate.

Albumins↗
PubMed1984

Investigations into the volatility of female pheromones and the aggregation-inducing property of guanine in Argas (Persicargas) walkerae.

During investigations into the volatility of female pheromones of A. walkerae in a Y-shaped olfactometer, engorged conspecific male ticks responded weakly both to female-contacted filter paper discs and to intact females enclosed in nylon bags. In tests in which female-contacted filter paper discs were separated from engorged male ticks by means of a screen, no aggregation was observed. However, replete male ticks showed a vigorous response to liquefied air and hexane-trapped volatiles collected from intact females. Guanine showed a potent aggregation attraction for engorged and unfed larvae and 1st and 2nd stage nymphal ticks as well as for male and female imagines of A. walkerae over a wide concentration range. It is concluded that at least 2 pheromones, 1 volatile and 1 non-volatile, are operative in the communication system of this tick species.

Animals↗
PubMed1978

Chemical studies on tobacco smoke LIX. Analysis of volatile nitrosamines in tobacco smoke and polluted indoor environments.

Chemical-analytical data were presented illustrating that the mainstream smoke of tobacco products contains traces of volatile N-nitrosamines. The quantity of volatile nitrosamines in the sidestream smoke of cigarettes and cigars exceeds that in the mainstream smoke by at least a factor of 10. This observation led to model studies and analysis of air in bar cars of trains, in a local bar and other indoor atmospheres polluted by tobacco smoke. The results showed that, during one hour in a smoke-polluted indoor environment, one may inhale volatile nitrosamines in quantities equal to those in the mainstream smoke of 0.5-30 cigarettes. It is emphasized that there are, at present, no epidemiological data linking human respiratory cancers to volatile nitrosamines.

Air Pollution↗
PubMed1982

[Sublimatographic separation of fission products by beta-diketone complexes -fission products chelate complexes in the non-volatile M(beta-diketone)n produced directly by recoil effects].

The sublimatographic separation of volatile beta-diketonate complexes of fission products produced directly by the recoil atoms of fission products under exposure of a mixture of non-volatile M(beta-diketone)n and U-3 (JAERI) on neutron, was carried out. When Ba(acac)2 and K(acac) were used as catcher chelates, both samples did not deposited radioactive chelates and inactive chelates in the inner glass tube. But the volatile Zr (acac)4 chelates were mixed with the samples of Ba(acac)2+U-3 after irradiation, the radioactive chelates deposited together with the inactive chelates of Zr(acac)4 at the same position in the inner glass tube. The nuclides in the deposited zones were mainly 97Zr-97Nb, 91mY, 92Y and 93Y. On the other hand, in the case of Y(Dpm)3 chelates mixed, the nuclides in the deposited zones of the radioactive and inactive chelates were 91mY, 92Y, 97Zr-97Nb, 141Ce and 143Ce. When the volatile Zr(acac)4 chelates were mixed with the sample of Ba(acac)2+U-3 after irradiation, the yield of deposited 97Zr nuclide was directly proportional to the amount of Zr-(acac)4 up to about 5 times against the amount of the irradiated sample.

Chelating Agents↗
PubMed1981

Effect of volatile fatty acids on blood flow and oxygen uptake by the dog colon.

The effects of volatile fatty acids on colonic hemodynamics and oxygen uptake were examined in a denervated autoperfused dog colon preparation. While measuring arterial pressure, colonic blood flow, venous pressure, and arteriovenous O2 difference, a Tyrode's solution containing acetic (75 mM), propionic (30 mM), and butyric acids (30 mM) was placed into the colon lumen. The volatile fatty acid mixture increased colonic blood flow (23.5%) and oxygen uptake (18.4%), yet did not affect oxygen extraction. Of the three fatty acids, only acetic acid (75 mM) could mimic the effects of the entire mixture on colonic hemodynamics and oxygen uptake. Butyric (30 mM) and propionic (30 mM) acids were without appreciable effects on colonic blood flow and oxygen uptake. The vehicle for the volatile fatty acids, Tyrode's did not alter blood flow, yet increased colonic oxygen uptake (18.7%) through an increase in oxygen extraction (18.3%). When compared with Tyrode's, acetic acid increased blood flow, yet did not alter oxygen uptake, while butyric and propionic acids did not alter colonic blood flow, yet inhibited colonic oxygen uptake. Close intraarterial infusion of acetic acid increased colonic blood flow and oxygen uptake. These data suggest that physiologic concentrations of volatile fatty acids (particularly acetic acid) significantly alter colonic flow.

Acetates↗
PubMedDate not supplied

Screening toxic effects of volatile organic compounds using Drosophila melanogaster.

The suitability of Drosophila melanogaster for biological screening of the toxic effects of volatile organic compounds was investigated. Adult flies were exposed to vapours of some organic solvents and gasoline under saturating conditions in the sublethal range. In some cases the dose-response relationship was studied. As a measure of the overall metabolism, CO2 production was recorded before and after exposure, including the recovery period, and the body activity was scored and classified as "normal behaviour", hyperactivity or excitement or narcosis. Significant differences were observed for the different solvents and volatile mixtures (vapours of acetone, benzene, methanol, toluene, xylene, diethylether, leaded and unleaded gasoline and diesel fuel). The length of the narcosis induced by the volatile organic compounds correlated well with their octanol-water coefficients. After exposure to benzene, toluene and gasoline a marked increase in the CO2 production during narcosis was observed. Methanol exposure led to a long-lasting increase in CO2 production, but did not cause narcosis. There were also differences in the behaviour (body activities) in the recovery phase between the solvents tested. Thus, the results from these experiments suggest that the measurement of CO2 production combined with the scoring of body activities in Drosophila can be used as a sensitive screening procedure in inhalation toxicology, revealing different types of toxic reactions for different types of volatile compounds.

Animals↗
PubMed1989

Volatile nitrosamine levels and genotoxicity of food samples from high-risk areas for nasopharyngeal carcinoma before and after nitrosation.

Traditional life-style, especially food habits, infection by Epstein-Barr virus (EBV) and genetic factors, have been associated with an increased risk of nasopharyngeal carcinoma (NPC). N-Nitroso compounds and other carcinogens either present in food or formed endogenously, as well as food constituents that activate EBV, have been suspected as etiological factors in NPC pathogenesis. For their characterization preserved food items, frequently consumed in NPC endemic areas in Tunisia, South China and Greenland, were sampled and screened for the presence of mutagens and volatile nitrosamines before and after nitrosation. Aqueous extracts as well as 2 organic extracts of the samples were assayed for genotoxicity in 2 Salmonella typhimurium strains and the SOS chromotest. The same extracts had previously been analyzed for volatile nitrosamines and for EBV-activating substances in Raji cells. In our study, 13 out of 16 food samples showed a weak, directly-acting genotoxicity in the SOS chromotest in at least one of the extracts, but only one sample from Greenland was found to be weakly mutagenic in Salmonella TA 98. Chemical nitrosation for 9 out of 15 samples of aqueous food extracts increased the genotoxic effect in the SOS chromotest. Levels of volatile nitrosamines were also elevated for 12 out of 15 samples; highest levels of N-nitrosodimethylamine were found in hard salted and dried fish from China (1,200 micrograms/kg) and highest N-nitrosopyrrolidine levels in a Tunisian spice (3,840 micrograms/kg). In non-nitrosated aqueous food extracts, the level of volatile nitrosamines and genotoxic activities were not correlated with the EBV-inducing activity of the same samples. After chemical nitrosation, EBV-inducing activity was decreased or showed no change and was not correlated with increases in either the genotoxicity or the nitrosamine levels. Our results suggest that EBV-activating compounds belong to a different class of substances. However, there was an association between the changes in genotoxicity and nitrosamine levels due to nitrosation.

Carcinoma↗
PubMed2000

Gene responses in bean leaves induced by herbivory and by herbivore-induced volatiles.

Plant-plant interactions via herbivory-induced leaf volatiles could result in the induction of defense responses against aggressive biotic agents in plants. In this study, cDNA microarray technology showed comprehensive gene activation in lima bean leaves that were exposed to volatiles released from the neighboring leaves infested with spider mites. The infestation with spider mites and the herbivory-induced volatiles enhanced 97 and 227 gene spots on the microarray tip printed with 2032 lima bean cDNA, respectively. These genes are related to such broad functions as responses to pathogenesis, wounding, hormones, ethylene biosynthesis, flavonoid biosynthesis, (post) transcriptional modifications, translations, chaperones, secondary signaling messengers, membrane transports, protein/peptide degradations, and photosynthesis. We therefore conclude that herbivorous damage and herbivory-induced volatiles elicit comprehensive and drastic changes of metabolisms in leaves.

Animals↗
PubMed1978

[Development of volatile compounds from radicals arising during intermediate steps of the lipoxygenase-reaction (author's transl)].

The development of volatile compounds arising from radicals during intermediate reaction steps of the lipoxygenase-linoleic-acid-reaction (from soy) was investigated in model experiments with defined conditions. The results indicate as follows: Among the volatile compounds formed, hexanal has a special position. Its development is closely connected to the enzymatic formation of the 13-linoleic-acid-hydroperoxide because it is formed from the 13-linoleic-acid-peroxy-radical, which is a direct precursor of the 13-linoleic-acid-hydroperoxide. The other volatile products are apparently formed in the same way as by autoxidation. Their development is favoured by lack of oxygen, when the primarily formed linoleic-acid-radicals cannot react rapidly with the oxygen-radicals to form hydroperoxides. A small part of the volatile compounds is formed by autoxidation which always accompanies the enzymatic reaction.

Antioxidants↗
PubMed2003

A female-specific attractant for the codling moth, Cydia pomonella, from apple fruit volatiles.

Host plant-derived esters were investigated as potential female-specific attractants for the codling moth (CM), Cydia pomonella (L.), a key pest of apples worldwide. The behavioural effects of single and combined volatile compounds and of a natural odour blend were examined using olfactometry and wind-tunnel bioassays. The apple-derived volatile butyl hexanoate attracted mated females while it was behaviourally ineffective for males over a dosage range of more than three orders of magnitude in olfactometer assays. Female CM preferred this kairomone to the headspace volatiles from ripe apples. Both no-choice and choice trials in the wind-tunnel suggested that female moths might be effectively trapped by means of this compound. In contrast, headspace volatiles collected from ripe apple fruits as well as a blend containing the six dominant esters from ripe apples were behaviourally ineffective. A female-specific repellency was found for the component hexyl acetate in the olfactometer, but this ester had no significant effect in the wind-tunnel. Butyl hexanoate with its sex-specific attraction should be further evaluated for monitoring and controlling CM females in orchards.

Animals↗
PubMed2002

Development of a robust technique for sampling volatile metal(loid)s in wetlands.

The formation of volatile organic and inorganic metals and metalloids in aquatic environments is a known, but not very intensively investigated, process. Several techniques have been developed over the past 10 years to determine these trace components. These techniques are of limited use in wetland environments, where samples have to be taken from the soil-water interface, and require an immediate sample analysis due to thermodynamic instabilities of the volatile metal(loid)s. This paper presents an innovative sampling technique for total concentrations of volatile metal(loid)s in wetlands, based on an in situ gas-water separation via a porous PTFE membrane and stabilising the volatile metal(loid)s in a liquid sorbent (NaOCl solution). Samples may thus be collected even at remote sites, where longer storage times have to be accounted for. The sampling system was tested by means of a laboratory facility simulating the generation of arsine and dimethyl arsine under abiotic conditions as well as under field conditions. Results for sampling efficiency, reproducibility, and long-term storage are presented. Application of the sampling system in the field is shown.

Adsorption↗
PubMed1996

Gas generation and preconcentration coupled to gas phase molecular absorption spectrometry: a powerful tool for the simultaneous determination of analytes forming volatile compounds.

Different methods for a simultaneous determination of several analytes forming volatile compounds at room temperature are described. The main steps of these methods are: continuous generation, collection in a cryogenic trap, revolatilization, measurement of the volatile compounds by Gas Phase Molecular Absorption Spectrometry and resolution by multi-wavelength methods. Several mixtures containing 2, 3 or 4 components have been studied: 1) elements forming covalent hydrides; 2) arsenic organometallic compounds forming volatile gases with a similar structure to arsine; and 3) sulphur species that can evolve volatile compounds. Under the optimum conditions obtained for each mixture, detection limits range from 0.8 ng/mL (dimethylarsinic acid) to 2 microg/mL (SCN(-)).

Journal Article↗