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Six coriander accessions of different origins were grown on an experimental field in Mošorin, Serbia during 2014. The GC/MS analysis of the essential oil showed that the major components in all samples were linalool (69.3–72.0%), γ-terpinene (6.0–9.6%) and α-pinene (6.7–8.2%), while other compounds were present at less than 5%. Antifungal activity of coriander oils against two phytopathogenic fungi from Colletotrichum genus (C. acutatum and C. gloeosporioides) was evaluated using the inverted petriplate method. Experiments show that coriander essential oil has antifungal properties against the apple bitter rot pathogens from Colletotrichum genus, but only at higher application rates (≥ 0.16 μl/ml of air). According to the obtained data, it can be concluded that tested coriander accessions differ in essential oil content and composition, as well as in influence on mycelial growth. Coriander essential oil has potential for being applied as a biological control agent against these two fungi from Colletotrichum genus.
This paper presents the results of investigations on the emission of volatile organic compounds (VOC) from oak wood surfaces finished with acrylic waterborne lacquers. The lacquers selected for the experiments were characterised by a different content of solids, fluctuating between 32 and 38%. The volatile organic compounds were analysed using a gas chromatography technique combined with mass spectrometry and thermal desorption (GC/MS/TD). Tenax TA was employed as an adsorption medium. The obtained results indicate that volatile organic compound emissions from the experimental waterborne lacquers varied widely from 388 to 1794 μg/m3. The most important constituents of emissions included compounds that belonged mainly to glycol ethers as well as aliphatic and aromatic hydrocarbons.
The hydrodistilled essential oil of aerial parts of Tanacetum balsamita L. ssp. balsamitoides (Schultz-Bip.) Asteraceae growing spontaneously in Tabriz (North-West of Iran) was analyzed by GC-MS. Twenty-three components comprising 96.83% of the total essential oil were identified. Oxygenated monoterpens (87.93%) were the major class of identified components. Sesquiterpene hydrocarbons (6.66%) were the second class. Main monoterpene constituents of the aerial parts essential oil were carvone (49.11%), α-thujone (24.6%), β- thujone (2.68%) and 1,8-cineole (2.59%). β-bisabolene (4.44%) a sesquiterpene hydrocarbone was also present in significant amounts. According to the volatile oil profile, T. balsamita L. ssp. balsamitoides (Schultz-Bip.) plant studied in the present experiment was belong to the carvone/α-thujone chemotype that produces appreciable amounts of β-bisabolene.
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During the illness are released volatile organic compounds with specific smell which could have in diagnosis of diseases. The first aim of the study was qualitative and quantitative analysis of exhaled breath samples obtained from patients with lung cancer, healthy volunteers and people with other lung diseases by gas chromatography-mass spectrometry. This study showed that twenty compounds propane, ethanol, isobutane, butane, propanal, 1-propanol, 2-propanol, 2-methylfuran, 2-butanone, benzene, 2-pentanone, pentanal, hexanal, cyclohexanone, 4-heptanone, 2,4-dimethylheptane, 2,3,4-trimethylhexane, 2,3,5-trimethylhexane, 4-methyloctane, α-pinene separated two research groups of patients and healthy controls. The second goal was to evaluate the sensitivity and specificity of canine scent detection using 5 station scent lineup. Among lung cancer patients and complementary samples, overall sensitivity of canine scent detection was 85.54%, while specificity was 71.84%.
Aerial parts of Mentha pulegium L. collected from south east of Algeria (Reguiba, El-Oued) possessed an essential oil in 2.34% (v/w) yield. GC and GC-MS analysis of the oil revealed recognition of Thirty-seven compounds, representing 95.02% (area percent) of the total oil composition. Oil was rich in Oxygenated hydrocarbons, exhibited higher percentage of Pulegone (46.31%) followed by Piperitenone (23.3%), Menthone (6.2%) and Limonene (4.7%). The antioxidant activity by DPPH free radical scavenging bioassay (IC50 = 157 μl/ml).
This study shows the sensitivity of using silicone rubber passive sampler (SR-PS) and gas chromatography with mass spectrometer (GC-MS) detection for monitoring and identification of polycyclic aromatic hydrocarbons in surface water systems. The analysis was performed for eighteen PAHs compounds after pre-concentration using Soxhlet extraction method. By comparison, a total of 13 PAHs were detected in the spot water samples, of which none was quantifiable. The freely dissolved PAH concentrations were found to range from 0.17 ng/L to 0.76 ng/L at Ugieriver. The use of fluorine d10 as Performance reference compound(PRC) gives a sampling rates of 8.14 (L/day) for silicone rubber passive samplers. Analysis of PAHs concentrations suggest the contaminants are mainly from pyrolytic sources. Overall it can be concluded that SR-PS are viable alternatives in the environmental monitoring of PAHs.
The ethyl acetate fractions of aqueous extracts from two submerged macrophytes Potamogeton malaianus and Potamogeton maackianus were analyzed by gas chromatograph-mass spectrometry (GC-MS). The allelopathic activities and joint effects of the main components in ethyl acetate fractions on Microcystis aeruginosa were also determined. The results indicated that primary compositions in the ethyl acetate fractions were fatty acids, phenolic acids and hydroxy fatty acids that possessed antialgal activities. The joint effect assay for palmitic acid, benzoic acid and lactic acid showed that the additional effects were observed in the mixed organic acid, namely, the inhibitory effects of mixture groups were stronger than that of each compound alone on the growth of M. aeruginosa.
The aim of this study was to determine the concentrations of volatile organic compounds found in the air in five production halls at a furniture manufacturing plant. Tests were performed in production halls, where machining operations were performed both on wood and wood-based materials, in shop halls in which surface-finishing operations were performed, as well as a finished goods warehouse.A Tenax TA synthetic sorbent was used to adsorb compounds found in the air.Volatile substances were analysed by gas chromatography combined with mass spectrometry and thermal desorption. It was found that the microclimate in the examined production halls varied. Differences were observed not only in the type of compounds detected in the shop halls, but also in their amounts. The analysed air contained a broad spectrum of volatile compounds, mainly alcohols, glycols, aromatic hydrocarbons, aldehydes, esters and terpenes. The total concentrationof volatile organic compounds (TVOC) found in the air in the examined production halls varied within a very broad range from 795 to 5113 μg/m3. The concentrations of volatile organic compounds identified in the production halls were markedly lower than those specified by Polish legal regulations - the Ordinance of the Minister of Labour and Social Policy of 2002 (with later amendments).
The Syrian Thymus cilicicus (Th. cilicicus) Boiss & Bal. and Thymus syriacus (Th. syriacus) Boiss chemical components were identified using GC-MS spectrometry. Sixteen constituents representing an average of 93.85% of the essential oil from Syrian Thymus cilicicus were characterized. The major average components in four collection rounds of Thymus cilicicus around the year were: thymol, carvacrol, γ-terpinene, carvyl acetate, dihydrocarvone and anis aldehyde. Eighteen components representing an average of 93.46% of the essential oil of Thymus syriacus were characterized. The major average components in four collection rounds of Thymus syriacus around the year were: carvacrol, dihydrocarvone, β-caryophyllene, p-cymene, farnesol, limonine, menthol, myrecene, γ-terpinene, terpinene- 4-ol and thymol. The integral antioxidant capacity of aqueous and essential oils extracts of both Thymus species: Th. syriacus and Th. cilicicus have been determined by means of a photochemiluminescence assay (PCL). The highest integral antioxidant capacity has been found for Th. syriacus and Th. cilicicus in Fahel mountain and Salah Aldin locations which have a value of total nmol equivalent per gram of dry material at 374.6 ± 0.94 and 475.80 ± 1.20 nmol TE/g DM, respectively.
An investigation of plants reach in lipophylic compounds and searching of sufficient raw material are being conducted due to rising scientists’ interest. Among them, we can count the plants of Fabaceae and Poaceae families. With the use of a gas-liquid chromatography method (GLC), the qualitative composition and the quantitative content of fatty acids and tocopherols in the lipophylic fraction of Glycine hispida, as well as sterols and fatty acids in the lipophylic fractions of fruits and grass of Setaria italica have been determined. In addition steroid and fatty-acid compositions of fruits of Setaria italica have been studied using the methods of gas chromatography/mass-spectrometry (GC/MS).
Urine is a major source of mammalian chemosignals. Among rodents, the sexual attractiveness and chemical constituents of urine vary with different reproductive stages. We confirmed the differing sexual attractiveness to males of the urine of lactating and non-lactating female root voles (Microtus oeconomus) and analyzed individual coding forms and lactation-specific putative pheromones, using gas chromatography-mass spectrometry (GC-MS). First, we documented the behavioral preference of male voles to urine odors of lactating and non-lactating females in a choice maze. The results showed that male voles engaged in more sniffing behavior and spent more time self-grooming in response to urinary odors of lactating females than to urinary odors of non-lactating females. We then used GC-MS to analyze the urine’s individual coding forms and potential chemosignals. We identified 34 volatile compounds, corresponding to 34 GC peaks, in the urine of female voles. The components identified in the urine samples included benzo- forms, alkanes, alkenes, acids, esters, pyrans, alcohols, and other volatile compounds. 12 basic volatiles were detected in all urine samples while others were specific to individuals. (E)5-octadecene and (N) hexadecanoic acid were specific to the lactating stage. A quantitative comparison of the relative abundances of the basic GC peaks showed no difference between the lactating and non-lactating stages, suggesting that individual identity is coded in digital form. We suggest that the urine of lactating females possesses stronger sexual attraction cues because of the presence of (E)5-octadecene and (N)hexadecanoic acid, which are putative lactating pheromones. However, the specific function of the pheromones should be assessed further by bioassay.
The aim of the research was to evaluate that the effect of symbiotic fermented cherry juice containing fructo oligosaccharide to enhance the growth and activity of probiotic strains include Lactobacillus acidophilus was tested for their antibiotic susceptibility, and tolerance to bile. Antifungal activity of symbiotic cherry juice could differ in their antagonistic activity against fungal disease which could be due to the metabolite secreted by the lactic acid bacteriocin specially type of organic acids and added fructo oligo saccharide as a probiotic and for food preservation synbiotic cherry juice was identified and their major compounds was detected using gas chromatographymass spectrum (gc-ms).
The qualitative and quantitative analysis of polycyclic aromatic hydrocarbons contamination in selected popular brands of fruit and herbal teas was performed using GC-MS method. Among all teas similar quality profiles of PAHs were observed. In all determined compounds 4 light PAHs (phenanthrene, anthracene, fluoranthene, pyrene) from the group of PAHs listed by EPA were predominant. From group of 15 PAHs, marked out for analysis by The UE Scientific Committee on Food, only benzo[a]anthracene, chrysene, 5-metylchrysene, benzo[b]fluoranthene and benzo[k]fluoranthene were stated, although, their levels were relatively low. Benzo[a]pyrene and the most carcinogenic PAHs, namely dibenzopyrenes, were not detected. Moreover, the GC-MS analysis revealed significant differences in contamination level of particular brands of teas among all fruit and herbal teas under investigation.
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