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PubMed1997

Fungal colonization of air filters and insulation in a multi-story office building: production of volatile organics.

Secondary air filters in the air-handling units on four floors of a multi-story office building with a history of fungal colonization of insulation within the air distribution system were examined for the presence of growing fungi and production of volatile organic compounds. Fungal mycelium and conidia of Cladosporium and Penicillium spp. were observed on insulation from all floors and both sides of the air filters from one floor. Lower concentrations of volatile organics were released from air filter medium colonized with fungi as compared with noncolonized filter medium. However, the volatiles from the colonized filter medium included fungal metabolites such as acetone and a carbonyl sulfide-like compound that were not released from noncolonized filter medium. The growth of fungi in air distribution systems may affect the content of volatile organics in indoor air.

Acetone↗
PubMed2005

Inhibition of E-selectin-mediated leukocyte adhesion by volatile anesthetics in a static condition.

PURPOSE: Leukocyte recruitment from blood vessels to inflamed tissues is the central step in the process of inflammation. This may cause damage of the inflamed tissues in the case of severe inflammatory conditions such as ischemia reperfusion or graft rejection. Adhesion molecules, such as E-selectin, are induced on activated endothelium and play an important role in this process. Volatile anesthetics protect tissues or organs in such conditions, and inhibition of leukocyte adhesion by anesthetics has been implicated. However, little is known about how the anesthetics act on individual adhesion molecules. We examined the effects of volatile anesthetics on E-selectin mediated leukocyte adhesion in a static condition using HL-60 cells, a granulocyte cell line, and E-selectin-coated plates as well as cytokine-activated human umbilical vein endothelial cells (HUVEC). METHODS: The adhesion assay was carried out by overlaying fluorescence-labeled HL-60 cells on E-selectin-coated plates or cytokine-activated HUVEC. E-selectin in the coated plates or activated HUVEC were quantified by enzyme-linked immunosorbent assay. E-selectin in the activated HUVEC was analyzed by immunoblot. RESULTS: Isoflurane and sevoflurane concentration-dependently suppressed adhesion of HL-60 cells to E-selectin-coated plates. Although isoflurane did not change the amount of expression, or the molecular weight of E-selectin in the activated HUVEC, it significantly suppressed HL-60 cell adhesion to activated HUVEC. CONCLUSION: Volatile anesthetics suppress E-selectin-mediated cell adhesion in a static condition without changing the expression of E-selectin. A role for E-selectin in the organ protection by volatile anesthetics is suggested.

Anesthetics, Inhalation↗
PubMed2006

Behaviorally active green leaf volatiles for monitoring the leaf beetle, Diorhabda elongata, a biocontrol agent of saltcedar, Tamarix spp.

Biological activity and chemistry of host plant volatiles were investigated for Diorhabda elongata, Brullé (Coleoptera: Chrysomelidae), a biological control agent for the invasive tree, saltcedar (Tamarix spp., Tamaricaceae). Gas chromatographic-electroantennographic detection (GC-EAD) analysis of volatiles collected from adult D. elongata feeding on saltcedar foliage or from saltcedar foliage alone showed 15 antennally active compounds. These compounds were more abundant in collections from beetle-infested foliage. Antennally active compounds were identified by GC-mass spectrometry (MS) and confirmed with authentic standards. The emissions of the most abundant GC-EAD-active compounds, green leaf volatiles (GLV), were quantitated by GC-MS. A blend of four GLV compounds, mimicking the natural blend ratio, was highly attractive to male and female D. elongata in the field, and a combination of GLV and male-produced aggregation pheromone attracted significantly greater numbers of D. elongata than did either bait alone. A preliminary experiment with a blend of seven additional GC-EAD-active saltcedar volatiles did not show any behavioral activity. The combination of the pheromone and the green leaf odor blend could be a useful attractant in detecting the presence of the biocontrol agent, D. elongata, in stands of saltcedar newly colonized by the beetle.

Animals↗
PubMed1990

Aflatoxin production in cultures of Aspergillus flavus incubated in atmospheres containing selected cotton leaf-derived volatiles.

Aspergillus flavus, in solid culture, was exposed to individual selected, commercially obtained volatile compounds that were similar to volatile cotton leaf-derived components. The radial growth pattern of A. flavus and the production of aflatoxin were determined on these volatile exposed cultures. The most bioactive compounds C6-C9 alkenals, completely inhibited the growth of the fungus. Unexpected results demonstrated that 3-methyl-1-butanol and 3-methyl-2-butanol inhibited A. flavus growth by 20% but increased production of aflatoxin B1 by 1.5 to 2-fold. Other relationships of growth and aflatoxin production resulting from exposure to the bioactive volatiles are discussed.

Aflatoxin B1↗
PubMed1987

Application of polyurethane foam for sampling volatile mutagens from ambient air.

This paper reports the use of polyurethane foam (PUF) in the sampling of airborne mutagens too volatile to be retained by glass fibre filters. Air was sampled simultaneously with a glass fibre filter and PUF plugs, and the two extracts of the samples were tested for mutagenicity and analysed for polycyclic aromatic hydrocarbons (PAH). As PUF itself was found to contain mutagens, it was thoroughly rinsed, and a blank extract of the same PUF used for sampling was tested as a control. The resulting blank extracts were not mutagenic. In the first series of experiments, in which methanol was used as the extraction solvent, sampling induced clear-cut mutagenic effects in the PUF extracts. As the mutagenicity of the PUF itself appeared only with the use of methanol or other alcohols as extraction solvents, a second series of experiments was carried out in which acetone was used as the extraction solvent. In these experiments sampling induced no mutagenicity in the extracts. The discrepancy between the two series of experiments may be due to the absence of volatile mutagens in the second series, but another explanation may be an artefact induced by the solvent in the first series. Additional experiments suggest that sampling induces the formation, from PUF, of compounds mutagenic upon extraction with methanol. The study leads to the provisional conclusion that no volatile mutagens could be demonstrated in ambient air sampled by the use of PUF as an absorbent, notwithstanding the clear-cut effects of the filter extracts and the presence of volatile PAH in the PUF extracts.

Air Pollutants, Occupational↗
PubMed1987

Fluoranthene, a volatile mutagenic compound, present in creosote and coal tar.

Creosote, a coal-tar distillation product, contains mutagens which are volatile at 37 degrees C. After distillation of creosote we found that these volatile mutagens were present in the distillation fraction with the highest boiling range (greater than 360 degrees C). The "volatile mutagenic activity" was connected with the presence of fluoranthene, a polycyclic aromatic hydrocarbon. Commercially available fluoranthene was positive in the so-called "taped-plate assay" (the test system used for the detection of volatile mutagens) towards the strains TA98 and TA100 in the presence of S9 mix. The tested creosote and coal tar contained fluoranthene in concentrations of 5.2 and 2.2%, respectively.

Coal Tar↗
PubMed1989

Odor volatiles associated with microflora in damp ventilated and non-ventilated bin-stored bulk wheat.

Western hard red spring wheat, stored at 20 and 25% moisture contents for 10 months during 1985-86, was monitored for biotic and abiotic variables in 10 unheated bins in Winnipeg, Manitoba. The major odor volatiles identified were 3-methyl-1-butanol, 3-octanone and 1-octen-3-ol. The production of these volatiles was associated and correlated with microfloral infection. Ventilation, used for cooling and drying of grain, disrupted microfloral growth patterns and production of volatiles. The highest levels of 3-methyl-1-butanol occurred in 25% moisture content wheat infected with bacteria, Penicillium spp. and Fusarium spp. In non-ventilated (control) bins with 20% moisture content wheat, 3-methyl-1-butanol was correlated with infection by members of the Aspergillus glaucus group and bacteria. In control bins, 1-octen-3-ol production was correlated with infection of wheat of both moisture contents by Penicillium spp. The fungal species, isolated from damp bin-stored wheat and tested for production of odor volatiles on wheat substrate, included Alternaria alternata (Fr.) Keissler, Aspergillus repens (Corda) Saccardo, A. flavus Link ex Fries, A. versicolor (Vuill.) Tiraboschi, Penicillium chrysogenum Thom, P. cyclopium Westling, Fusarium moniliforme Sheldon, F. semitectum (Cooke) Sacc. In the laboratory, fungus-inoculated wheat produced 3-methyl-1-butanol; 3-octanone and 1-octen-3-ol were also produced, but less frequently. Two unidentified bacterial species isolated from damp wheat and inoculated on agar produced 3-methyl-1-butanol.

Alcohols↗
PubMed2004

Diagnostic potential of breath analysis--focus on volatile organic compounds.

Breath analysis has attracted a considerable amount of scientific and clinical interest during the last decade. In contrast to NO, which is predominantly generated in the bronchial system, volatile organic compounds (VOCs) are mainly blood borne and therefore enable monitoring of different processes in the body. Exhaled ethane and pentane concentrations were elevated in inflammatory diseases. Acetone was linked to dextrose metabolism and lipolysis. Exhaled isoprene concentrations showed correlations with cholesterol biosynthesis. Exhaled levels of sulphur-containing compounds were elevated in liver failure and allograft rejection. Looking at a set of volatile markers may enable recognition and diagnosis of complex diseases such as lung or breast cancer. Due to technical problems of sampling and analysis and a lack of normalization and standardization, huge variations exist between results of different studies. This is among the main reasons why breath analysis could not yet been introduced into clinical practice. This review addresses the basic principles of breath analysis and the diagnostic potential of different volatile breath markers. Analytical procedures, issues concerning biochemistry and exhalation mechanisms of volatile substances, and future developments will be discussed.

Air↗
PubMed2005

Evaluation of volatile ion-pair reagents for the liquid chromatography-mass spectrometry analysis of polar compounds and its application to the determination of methadone in human plasma.

A liquid chromatography method using volatile ion-pairing reagents and tandem mass spectrometry was developed to obviate observed matrix effect for ionizable polar compounds. The present study investigated the addition of volatile ion-pair reagents to the reconstitution solution instead of the mobile phase to enhance the efficiency of chromatographic separation and minimize the sensitivity loss due to the formation of ion-pairs. The volatile ion-pair reagents used were perfluorinated carboxylic acids with n-alkyl chains: heptafluorobutanoic acid (HFBA), nonafluoropentanoic acid (NFPA), tridecafluoroheptanoic acid (TDFHA) and pentadecafluorooctanoic acid (PDFOA). The model analytes evaluated were N-methylnicotinamide (MNA) chloride, N-methyl 2-pyridone 5-carboxamide (2PY) and phenylephrine. The effects of alkyl chain length and the concentrations of the ion-pair reagents on the retention of analytes were studied, as well as the effect of pH on the retention of phenylephrine. The volatile ion-pair reagents in the reconstitution solution showed significant effect on the retention of the ionizable polar compounds, and the sensitivity of detection was improved for plasma samples through decreasing the matrix effect. This methodology was successfully applied to establish a quantitative assay for the polar drug substance methadone in human plasma with a concentration range from 0.1 to 50 ng/mL. Ion-pair reagents not only shifted the retention time but also reduced the carry-over peak for methadone.

Analgesics, Opioid↗
PubMed2006

GC-MS SPME profiling of rhizobacterial volatiles reveals prospective inducers of growth promotion and induced systemic resistance in plants.

Chemical and plant growth studies of Bacilli strains GB03 and IN937a revealed that the volatile components 2,3-butanediol and acetoin trigger plant growth promotion in Arabidopsis. Differences in growth promotion when cytokinin-signaling mutants are exposed to GB03 versus IN937a volatiles suggest a divergence in chemical signaling for these two bacterial strains. To provide a comprehensive chemical profile of bacterial volatiles emitted from these biologically active strains, headspace solid phase microextraction (SPME) coupled with software extraction of overlapping GC-separated components was employed. Ten volatile metabolites already reported from GB03 and IN937a were identified as well as 28 compounds not previously characterized. Most of the newly identified compounds were branched-chain alcohols released from IN937a, at much higher levels than in GB03. Principal component analysis clearly separated GB03 from IN937a, with GB03 producing higher amounts of 3-methyl-1-butanol, 2-methyl-1-butanol and butane-1-methoxy-3-methyl. The branched-chain alcohols share a similar functional motif to that of 2,3-butanediol and may afford alternative structural patterns for elicitors from bacterial sources.

Arabidopsis↗
PubMedDate not supplied

Cardioprotection by volatile anesthetics.

Preconditioning describes a very powerful endogenous mechanism by which the heart may be protected against ischemia and reperfusion injury. Transient administration of a volatile anesthetic before a prolonged ischemic episode reduces myocardial infarct size to a degree comparable to that observed during ischemic preconditioning. Many components of the signal transduction pathways responsible for cardioprotection are shared by anesthetic and ischemic preconditioning. Exposure to volatile anesthetics generates small "triggering" quantities of reactive oxygen species (ROS) by directly interacting with the mitochondrial electron transport chain or indirectly through a signaling cascade in which G-protein-coupled receptors, protein kinases, and mitochondrial ATP-sensitive potassium (K(ATP)) channels play important roles. Several clinical studies also suggest that preconditioning by volatile anesthetics exerts beneficial effects in patients undergoing cardiac surgery. This review summarizes some of the recent major developments in the understanding of cardioprotection by volatile anesthetics.

Anesthetics, Inhalation↗
PubMed1999

Yeast culture volatiles as attractants for Rhodnius prolixus: electroantennogram responses and captures in yeast-baited traps.

Responses to air currents carrying volatiles from yeast cultures were measured by means of electroantennograms (EAGs) in the haematophagous bug Rhodnius prolixus and we tested yeast-baited traps in the laboratory. The volatiles liberated by yeast cultures generated a clear electrophysiological response, much higher than that obtained during stimulation with clean air. The addition of yeast cultures to the traps dramatically increased overnight capture. A modification performed on the traps was effective for this species, as the bugs were immobilised once they fell into the device. Our results demonstrate that yeast culture volatiles are attractive for R. prolixus. The results obtained by means of electroantennogram techniques represent the first electrophysiological evidence of the perception of yeast volatiles by the antennae of a triatomine bug. We discuss the relevance of our results in view of currently used sampling techniques and control strategies.

Animals↗
PubMed2002

The different responses of rat glutamate transporter type 2 and its mutant (tyrosine 403 to histidine) activity to volatile anesthetics and activation of protein kinase C.

Glutamate transporters play an important role in homeostasis of extracellular glutamate, a major excitatory neurotransmitter and a potential neurotoxin. In mammalian brain, glutamate transporter type 2 (EAAT2) is the most abundant form. Studies of molecular structures demonstrated that tyrosine 403 is critical in regulating the ion selectivity and transport mode of EAAT2. We hypothesized that wild type EAAT2 and its mutant at tyrosine 403 have different responses to volatile anesthetics, commonly used anesthetics that have been shown to affect glutamate transporter activity and decrease extracellular glutamate concentrations. We used site-directed mutagenesis and oocyte expression systems to test the hypothesis. Volatile anesthetics did not affect the activity of wild type EAAT2, isolated from rat hippocampus. When tyrosine 403 was replaced by histidine (Y403H), volatile anesthetics (isoflurane or halothane) at clinically relevant concentrations significantly decreased the transporter activity. Okadaic acid, a phosphatase inhibitor, significantly prolonged the isoflurane-induced inhibition. This inhibition was reversed by staurosporine and calphostin C, two protein kinase C (PKC) inhibitors, but not by the third PKC inhibitor, chelerythrine. Phorbol 12-myristate 13-acetate, a PKC activator, inhibited the activity of both wild type and Y403H EAAT2. This inhibition was also reversed by the same two PKC inhibitors but not by the third one. These results suggest that the switch of tyrosine 403 to histidine rendered EAAT2 sensitive to volatile anesthetics, a phenomenon that may require protein phosphorylation. PKC may be involved in the regulation of the activity of both wild type and Y403H EAAT2.

Amino Acid Substitution↗
PubMed2000

Inhibition of the human intermediate conductance Ca(2+)-activated K(+) channel, hIK1, by volatile anesthetics.

Ca(2+)-activated K(+) channels (K(Ca)) regulate a wide variety of cellular functions by coupling intracellular Ca(2+) concentration to membrane potential. There are three major groups of K(Ca) classified by their unit conductances: large (BK), intermediate (IK), and small (SK) conductance of channels. BK channel is gated by combined influences of Ca(2+) and voltage, while IK and SK channels are gated solely by Ca(2+). Volatile anesthetics inhibit BK channel activity by interfering with the Ca(2+) gating mechanism. However, the effects of anesthetics on IK and SK channels are unknown. Using cloned IK and SK channels, hIK1 and hSK1-3, respectively, we found that the currents of hIK1 were inhibited rapidly and reversibly by volatile anesthetics, whereas those of SK channels were not affected. The IC(50) values of the volatile anesthetics, halothane, sevoflurane, enflurane, and isoflurane for hIK1 inhibition were 0.69, 0.42, 1.01 and 1.03 mM, respectively, and were in the clinically used concentration range. In contrast to BK channel, halothane inhibition of hIK1 currents was independent of Ca(2+) concentration, suggesting that Ca(2+) gating mechanism is not involved. These results demonstrate that volatile anesthetics, such as halothane, enflurane, isoflurane, and sevoflurane, affect BK, IK, and SK channels in distinct ways.

Anesthetics, Inhalation↗
PubMed1997

Cellulysin from the plant parasitic fungus Trichoderma viride elicits volatile biosynthesis in higher plants via the octadecanoid signalling cascade.

Cellulysin, a crude cellulase from the plant parasitic fungus Trichoderma viride, induces the biosynthesis of volatiles in higher plants (Nicotiana plumbaginifolia, Phaseolus lunatus, and Zea mays) when applied to cut petioles by the transpiration stream. The pattern of the emitted volatiles largely resembles that from a herbivore damage or treatment of the plants with jasmonic acid (JA) indicating that cellulysin acts via activation of the octadecanoid signalling pathway. The treatment with cellulysin raises the level of endogenous JA after 30 min and is followed by a transient emission of ethylene after 2-3 h. Volatile production becomes significant after 12-24 h. Inhibitors of the JA pathway effectively block the cellulysin-dependent volatile biosynthesis.

Cellulase↗
PubMed2000

Volatiles as an indicator of fungal activity and differentiation between species, and the potential use of electronic nose technology for early detection of grain spoilage.

There is significant interest in methods for the early detection of quality changes in cereal grains. The development of electronic nose technology in recent years has stimulated interest in the use of characteristic volatiles and odours as a rapid, early indication of deterioration in grain quality. This review details the current status of this area of research. The range of volatiles produced by spoilage fungi in vitro and on grain are described, and the key volatile groups indicative of spoilage are identified. The relationship between current grain quality descriptors and the general classes of off-odours as defined in the literature, e.g. sour, musty, are not very accurate and the possible correlation between these for wheat, maize and other cereals, and volatiles are detailed. Examples of differentiation of spoilage moulds and between grain types using an electronic nose instrument are described. The potential for rapid and remote grain classification and future prospects for the use of such technology as a major descriptor of quality are discussed.

Journal Article↗
PubMed1998

Pathway for the biosynthesis of 4-methyl-1-hexanol volatilized from petal tissue of Nicotiana sylvestris.

Compounds volatilized from plant tissues play important roles in plant-insect and plant-herbivore interactions and are important to food quality/preference, and to the perfume and flavorant industries. While the chemistry of plant volatiles is well understood, less is known about the biosynthesis of this diverse group of compounds. This is particularly the case for non-terpenoid components such as volatile acyclic alcohols and their esters. Here we have studied metabolic pathways leading to formation of the anteiso-branched alcohol 4-methyl-1-hexanol volatilized by petal tissue of Nicotiana sylvestris. Evidence presented supports the involvement of steps in the pathways of both biosynthesis and degradation of isoleucine to form 2-oxo-3-methylvaleric acid then 2-methylbutyryl CoA. Results indicate that 2-methylbutyryl CoA is then elongated by addition of one acetate molecule via fatty acid synthase, followed by reduction to yield 4-methyl-1-hexanol. This pathway is in contrast to elongation of 2-oxo-3-methylvaleric acid via alpha-keto acid elongation leading to the formation of 4-methylhexanoyl acyl groups of tobacco leaf-trichome-secreted sugar esters.

Journal Article↗
PubMed2001

Effect of volatile metabolites of dill, radish and garlic on growth of bacteria.

In a model experiment plants were grown in sealed chambers on expanded clay aggregate under the luminance of 150 W/m2 PAR and the temperature of 24 degrees C. Seven bacterial strains under investigation, replicated on nutrient medium surface in Petri dishes, were grown in the atmosphere of cultivated plants. Microbial response was evaluated by the difference between colony size in experiment and in control. In control, bacteria grew in the atmosphere of clean air. To study the effects of volatile metabolites of various plant on microbial growth, the experimental data were compared with the background values defined for each individual experiment. Expanded clay aggregate, luminance, temperature, and sealed chamber (without plants) for the background were the same. Volatile metabolites from 28-days old radish plants have been reliably established to have no effect on the growth of microbes under investigation. Metabolites of 30-days old dill and 50-days old garlic have been established to have reliable bacteriostatic effect on the growth of three bacterial strains. Dill and garlic have been found to have different range of effects of volatile substances on bacterial growth. Volatile metabolites of dill and garlic differed in their effect on the sensitivity spectrum of bacteria. An attempt has been made to describe the obtained data mathematically.

Apiaceae↗