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1.
Molecules ; 28(24)2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38138598

RESUMEN

Alzheimer's disease is a global health problem due to the scarcity of acetylcholinesterase inhibitors, the basis for symptomatic treatment of this disease; this requires new approaches to drug discovery. In this study, we investigated the chemical composition and anticholinesterase activity of Eugenia valvata McVaugt (Myrtaceae) collected in southern Ecuador, which was obtained as an essential oil (EO) with a yield of 0.124 ± 0.03% (w/w); as a result of the chemical composition analysis, a total of 58 organic compounds were identified-representing 95.91% of the total volatile compounds-using a stationary phase based on 5% phenyl-methylpolysiloxane, as analyzed via gas chromatography coupled to mass spectrometry (GC-MS) and flame ionization detection (GC-FID). The main groups were hydrocarbon sesquiterpenes (37.43%), oxygenated sesquiterpenes (31.08%), hydrocarbon monoterpenes (24.14%), oxygenated monoterpenes (0.20%), and other compounds (3.058%). Samples were characterized by the following compounds: α-pinene (22.70%), α-humulene (17.20%), (E)-caryophyllene (6.02%), citronellyl pentanoate (5.76%), 7-epi-α-eudesmol (4.34%) and 5-iso-cedranol (3.64%); this research was complemented with an enantioselective analysis carried out using 2,3-diethyl-6-tert-butyldimethylsilyl-ß-cyclodextrin as a stationary phase chiral selector. As a result, α-pinene, limonene, and α-cadinene enantiomers were identified; finally, in the search for new active principles, the EO reported strong anticholinesterase activity with an IC50 of 53.08 ± 1.13 µg/mL, making it a promising candidate for future studies of Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Eugenia , Aceites Volátiles , Sesquiterpenos , Aceites Volátiles/química , Ecuador , Acetilcolinesterasa , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/análisis , Cromatografía de Gases y Espectrometría de Masas , Monoterpenos Bicíclicos/análisis , Sesquiterpenos/química , Monoterpenos/química
2.
Environ Pollut ; 319: 121016, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36610651

RESUMEN

The land-sea breeze circulation significantly impacts the atmospheric transport of organic aerosols in coastal regions. However, the links between organic aerosols and land-sea breezes remain poorly understood. In this study, organic marker compounds for biomass burning, primary biological aerosols, biogenic and anthropogenic secondary organic aerosols (SOA) in fine particles from a coastal city in East China were analysed using gas chromatography-mass spectrometry. Land-sea breeze circulations were identified to explore their potential influence on organic molecular compositions. Organic marker compounds showed obvious diurnal/seasonal patterns. Surprisingly, due to the combined influence of weakened East Asian monsoons and land-sea breezes, all detected organic markers decreased except α/ß-pinene SOA markers during land-sea breeze periods in early autumn; whereas, all the organic markers increased except α/ß-pinene SOA markers, pollen and plant debris markers during land-sea breeze periods in early spring. Furthermore, the reaction pathway and aging of biogenic SOA were also related to land-sea breezes. During the land-sea breeze periods, the ratios of 2-methylglyceric acid (2-MGA) to 2-methyltetrols increased in early autumn, indicating that more isoprene-derived SOA generated from the high-NOx (nitrogen oxides) pathway when the land-sea breezes occurred; while the ratios decreased in early spring, this may be related to the chemical transformation of 2-MGA to 2-MGA sulfates. Changes in the ratio of monoterpene SOA markers demonstrate that monoterpene SOA was relatively aged during sea breeze periods, while it was fresher when the land breeze occurred. Although boundary layer height, emissions, gas/particle partitioning, etc. are important reasons for the diurnal variations of organic aerosols, night/day ratios of molecular markers increased obviously when land-sea breezes occurred in both early autumn and early spring. Our results provide new insights into the shift in the chemical composition of organic aerosols over coastal areas that are influenced by land-sea breezes.


Asunto(s)
Contaminantes Atmosféricos , Compuestos Orgánicos , Monoterpenos Bicíclicos/análisis , Compuestos Orgánicos/análisis , Aerosoles/análisis , China , Contaminantes Atmosféricos/análisis
3.
Chemosphere ; 308(Pt 2): 136412, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36108761

RESUMEN

The abatement of indoor volatile organic compounds (VOCs) represents a major challenge due to their environmental risk, wide nature and concentration variability. Biotechnologies represent a cost-effective, robust and sustainable platform for the treatment of hazardous VOCs at low and fluctuating concentrations. However, they have been scarcely implemented for indoor air purification. Thus, little is known about the influence of the reactor configuration or the VOC nature and concentration variability on the removal, resilience and the microbial population of bioreactor configurations susceptible to be implemented, both in indoors and industrial environments. The present study aims at comparing the removal performance of four VOCs with different hydrophobicity and molecular structure -acetone, n-hexane, α-pinene and toluene-at two inlet concentrations (5 and 400 mg m-3), which mimics the concentrations of contaminated indoor and industrial air. To this aim a stirred tank, flat biofilm and latex-based biocoated flat bioreactor were comparatively evaluated. The results demonstrated the superior performance of the stirred tank reactor for the removal of hydrophilic VOCs at high inlet concentrations, which achieved removals >99% for acetone and toluene. At low concentrations, the removal efficiencies of acetone, toluene and α-pinene were >97% regardless of the bioreactor configuration tested. The most hydrophobic gas, n-hexane, was more efficiently removed in the flat biofilm reactor without latex. The microbial community analyses showed that the presence of VOCs as the only carbon and energy source didn't promote the growth of dominant bacterial members and the populations independently evolved in each reactor configuration and operation mode. The fungal population was more diverse in the biofilm-based bioreactors, although, it was mainly dominated by uncultured fungi from the phylum Cryptomycota.


Asunto(s)
Microbiología del Aire , Contaminación del Aire Interior , Contaminación del Aire , Compuestos Orgánicos Volátiles , Acetona/análisis , Contaminación del Aire/análisis , Contaminación del Aire/prevención & control , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/prevención & control , Monoterpenos Bicíclicos/análisis , Reactores Biológicos , Carbono/análisis , Hexanos/análisis , Látex , Tolueno/análisis , Compuestos Orgánicos Volátiles/análisis
4.
Acta Chim Slov ; 68(3): 728-735, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34897537

RESUMEN

Hydroperoxides are of great importance in the fields of atmospheric and biological chemistry. However, there are several analytical challenges in their analysis: unknown and usually low UV absorption coefficients, high reactivity, thermal instability, and a lack of available reference standards. To overcome these limitations, we propose a GC-FID approach involving pre-column silylation and quantification via the effective carbon number approach. Four hydroperoxides of α-pinene were synthesized in the liquid phase with singlet oxygen and identified using literature data on isomer yield distribution, MS spectra, estimated boiling temperatures of each isomer (retention time), their thermal stability and derivatisation rate. The developed procedure was used for the determination of hydroperoxides in bottled and autooxidised turpentine. We anticipate that this method could also be applied in atmospheric chemistry, where the reactivity of singlet oxygen could help explain the high formation rates of secondary organic aerosols.


Asunto(s)
Monoterpenos Bicíclicos/análisis , Peróxidos/análisis , Cromatografía de Gases , Ionización de Llama , Espectrometría de Masas , Trementina/análisis
5.
Molecules ; 26(18)2021 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-34577162

RESUMEN

The present paper reports the GC-HS-SPME analysis of volatile emission and GC-MS analysis of chemical composition of essential oil of R. coriaria fruits of eight different samples of R. coriaria L. fruits ("sumac" folk name), collected from Jordanian agricultural field and the local market. The analyses show an important variability among the Sumac samples probably due to the origin, cultivation, harvesting period, drying, and conservation of the plant material. The main class of component present in all samples was monoterpenes (43.1 to 72.9%), except for one sample which evidenced a high percentage of sesquiterpene hydrocarbons (38.5%). The oxygenated monoterpenes provided a contribution to total class of monoterpenes ranging from 10.1 to 24.3%. A few samples were rich in monoterpene hydrocarbons. Regarding the single components present in all the volatile emissions, ß-caryophyllene was the main compound in most of the analyzed samples, varying from 34.6% to 7.9%. Only two samples were characterized by α-pinene as the main constituent (42.2 and 40.8% respectively). Essential oils were collected using hydro-distillation method. Furfural was the main constituent in almost all the analyzed EOs (4.9 to 48.1%), except in one of them, where ß-caryophyllene was the most abundant one. ß-caryophyllene ranged from 1.2 to 10.6%. Oxygenated monoterpenes like carvone and carvacrol ranged from 3.2-9.1% and 1.0-7.7% respectively. Cembrene was present in good amount in EO samples EO-2 to EO-8. The antioxidant capacities of the fruit essential oils from R. coriaria were assessed using spectrophotometry to measure free radical scavenger 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and inhibition of ß-carotene bleaching (BCB). The essential oils from the fruits of the different samples of R. coriaria exhibited the MIC value ranging from 32.8 to 131.25 µg/mL against S. aureus ATCC 6538 and 131.25 to 262.5 µg/mL against E. coli ATCC 8739. The MIC values of ciprofloxacin were 0.59 and 2.34 µg/mL against S. aureus ATCC 6538 and E. coli ATCC 8739, respectively.


Asunto(s)
Frutas/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Aceites de Plantas/química , Aceites de Plantas/farmacología , Rhus/química , Antibacterianos/química , Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Monoterpenos Bicíclicos/análisis , Destilación , Escherichia coli/efectos de los fármacos , Cromatografía de Gases y Espectrometría de Masas , Jordania , Monoterpenos/análisis , Aceites Volátiles/análisis , Aceites de Plantas/análisis , Sesquiterpenos Policíclicos/análisis , Análisis de Componente Principal , Staphylococcus aureus/efectos de los fármacos
6.
Molecules ; 26(10)2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-34063513

RESUMEN

Chemical compositions of plants are affected by the initial nutrient contents in the soil and climatic conditions; thus, we analyzed for the first time the effects of soil and leaf nutrients on the compositions of the essential oils (EOs) of Siparuna muricata in four different localities in Ecuador. EOs were obtained by hydrodistillation and analyzed by gas chromatography/mass spectrometry (GC/MS) and a gas chromatography/flame ionization detector (GC/FID). Enantiomeric distribution by GC/MS was determined, modifying the enantiomeric separation of ß-pinene, limonene, δ-elemene, ß-bourbonene, cis-cadina-1 (6), 4-diene and atractylone. A total of 44 compounds were identified. The most representative for L1 were guaiol, atractylone and 4-diene; for L2, cis-cadina-1(6),4-diene and myrcene; for L3, atractylone, myrcene and germacrene B; and finally, L4 germacrene B, myrcene and cis-cadina-1(6),4-diene. Correlations between soil- leaf chemical elements such as Al, Ca, Fe, Mg, Mn, N and Si in the different localities were significant with chemical composition of the essential oil of Siparuna muricata; however, correlations between soil and leaf K, P, and Na were not significant. Cluster and NMDS analysis showed high dissimilarity values of secondary metabolites between four localities related with changes in soil- leaf nutrients. Thus, the SIMPER routine revealed that not all secondary metabolites contribute equally to establishing the differences in the four localities, and the largest contributions are due to differences in guaiol, cis-cadina-1(6),4-diene, atractylone and germacrene. Our investigation showed for the first time the influences of altitude and soil- leaf chemical elements in the chemical composition of the EOs of S. muricata.


Asunto(s)
Laurales/química , Aceites de Plantas/química , Suelo/química , Monoterpenos Bicíclicos/análisis , Ecuador , Ionización de Llama , Cromatografía de Gases y Espectrometría de Masas , Limoneno/análisis , Aceites Volátiles/química , Hojas de la Planta/química , Metabolismo Secundario , Sesquiterpenos/análisis
7.
Molecules ; 26(8)2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33923848

RESUMEN

Lippia alba (Mill.) N. E. Br. (Verbenaceae) is an aromatic shrub whose essential oils have stood out as a promising source for application in several industrial fields. In this study, the essential oils chemical characterization of eight new L. alba genotypes was performed. The selected materials were collected from the Active Germplasm Bank of the Agronomic Institute and the essential oils were extracted by hydrodistillation. Flow-modulated comprehensive two-dimensional gas chromatography coupled to mass spectrometry (GC×GC-MS) was employed for chemical characterization and evaluation of possible co-eluted compounds. In addition, the chemical analyses were submitted to multivariate statistical analyses. From this investigation, 73 metabolites were identified in the essential oils of the genotypes, from which α-pinene, ß-myrcene, 1,8-cineole, linalool, neral, geranial, and caryophyllene oxide were the most abundant compounds among the accessions. This is the first report disclosing α-pinene in higher amounts in L. alba (19.69%). In addition, sabinene, trans-verbenol, myrtenol, (E)-caryophyllene, α-guaiene, germacrene D, and α-bulnesene were also found in relevant quantities in some of the genotypes, and myrtenal and myrtenol could be well separated through the second dimension. Such results contributed to the understanding of the chemical composition of those new genotypes, being important to drive a future industrial applicability and studies in genetic breeding.


Asunto(s)
Lippia/química , Aceites Volátiles/análisis , Monoterpenos Acíclicos/análisis , Monoterpenos Bicíclicos/análisis , Monoterpenos Bicíclicos/química , Cromatografía de Gases y Espectrometría de Masas , Genotipo , Aceites de Plantas , Terpenos/análisis
8.
J Oleo Sci ; 70(5): 713-719, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33840661

RESUMEN

The volatile principles emitted from different aerial organs of two S. palaestina Benth. populations (Mediterranean (Med) and Irano-Turanian (IrT)) growing wild in Jordan were extracted by Solid Phase Micro-Extraction (SPME) and analysed by GC/MS technique. Sesquiterpene hydrocarbons dominated stems (59.38%, 49.67%) and leaves (93.28%, 32.39%) emissions from Med and IrT zones, respectively while monoterpene hydrocarbons had the major contribution to the aroma of pre-flowering buds (78.62%, 74.96%), opened flowers (76.12%, 59.99%) and petals (69.57%, 54.28%) and were mostly represented by sabinene (in Med zone) and ociemene isomers (Z & E) in IrT zone. Multivariate analysis classified the two populations into two different clusters based on their origin and indicated the occurrence of two ecotypes of this species. Different organs from the same collection site showed emission profiles of similar chemical composition.


Asunto(s)
Monoterpenos Bicíclicos/análisis , Flores/química , Monoterpenos/análisis , Odorantes/análisis , Hojas de la Planta/química , Tallos de la Planta/química , Salvia/química , Salvia/clasificación , Sesquiterpenos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Jordania , Análisis Multivariante , Extracción en Fase Sólida/métodos
9.
Nat Prod Res ; 35(1): 162-166, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31165644

RESUMEN

Glycyrrhiza echinata L. is a perennial plant of considerable commercial importance in medicine, pharmaceuticals, cosmetics, and tobacco industries and the production of food additives as flavoring and sweetening agent. This study, variation on composition and yield of essential oil from the underground parts of five accessions of G. echinata growing wild in northern Iran was investigated. Results showed high variability for the main constituents of essential oil among accessions of G. echinata. The presence of α-pinene and myrcene in two accessions suggests that these volatiles could serve as chemotaxonomic markers and also might be considered as potentially relevant for taste. The presence of ß-caryophyllene and α- caryophyllene in three accessions could be strong potential for being used in medical applications (anticancer and analgesic properties). Generally, the essential oils from G. echinata and other species could be very competitive targets for phytochemical and food studies.


Asunto(s)
Glycyrrhiza/química , Aceites Volátiles/química , Aceites de Plantas/química , Monoterpenos Acíclicos/análisis , Alquenos/análisis , Monoterpenos Bicíclicos/análisis , Irán , Sesquiterpenos Monocíclicos/análisis , Monoterpenos/análisis , Aceites Volátiles/análisis , Sesquiterpenos Policíclicos/análisis , Sesquiterpenos/análisis
10.
J Sci Food Agric ; 101(8): 3280-3289, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33222189

RESUMEN

BACKGROUND: The Citrus reticulata 'Chachi' pericarp (CRCP) is one cultivar of Citri Reticulatae Pericarpium (Chenpi), which is widely applied in medicine and food. To determine the potential value of CRCP harvested at different stages and subjected to different drying processes, the dynamic changes in the bioactive components were profiled and evaluated in this study. RESULTS: The contents of all non-volatile components, i.e. synephrine, limonin, phenolic acids and flavonoids, decreased with delayed harvest time. The volatiles thujene, α-pinene, ß-pinene, d-citronellol, d-citronellal, decanal, linalool, geraniol, l-cis-carveol, terpinen-4-ol, α-terpineol, carvacrol, perillaldehyde, methyl 2-(methylamino)benzoate and d-limonene were considered the characteristic components for distinguishing CRCP harvested at different stages. Phenolic acids, synephrine and limonin were stable at different drying temperatures; however, high-temperature drying at 60 °C induced a significant transformation in the flavonoids (especially polymethoxyflavones) and volatile substances in CRCP. CONCLUSIONS: The results suggested that most of the bioactive components declined with the growth of Citrus reticulata 'Chachi'. And it is believed that the fresh peel should be naturally sun-dried or dried at low temperature (30 or 45 °C) rather than at high temperature (60 °C) to prevent excessive loss of nutrients. © 2020 Society of Chemical Industry.


Asunto(s)
Citrus/química , Manipulación de Alimentos/métodos , Frutas/crecimiento & desarrollo , Extractos Vegetales/química , Monoterpenos Acíclicos/análisis , Monoterpenos Bicíclicos/análisis , Citrus/crecimiento & desarrollo , Monoterpenos Ciclohexánicos/análisis , Flavonoides/análisis , Frutas/química , Temperatura
11.
BMC Plant Biol ; 20(1): 500, 2020 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-33143644

RESUMEN

BACKGROUND: Plants are known to emit diverse volatile organic compounds (VOCs), which may function as signaling substances in plant communication with other organisms. Thuja occidentalis, which is widely cultivated throughout China, releases aromatic VOCs into the air in winter and early spring. The relationship of this cultivated plant with its neighboring plants is necessary for the conservation of biodiversity. RESULTS: (-)-α-thujone (60.34 ± 5.58%) was found to be the major component in VOCs from the Shenyang population. The essential oils (EOs) from the Kunming and Shenyang populations included the major components (-)-α-thujone, fenchone, (+)-ß-thujone, and (+)-hibaene, identified using GC-MS analyses. (-)-α-thujone and (+)-hibaene were purified and identified by NMR identification. EOs and (-)-α-thujone exhibited valuable phytotoxic activities against seed germination and seedling growth of the plants Taraxacum mongolicum and Arabidopsis thaliana. Moreover, the EOs displayed potent inhibitory activity against pathogenic fungi of maize, including Fusarium graminearum, Curvularia lunata, and Bipolaris maydis, as well as one human fungal pathogen, Candida albicans. Quantitative analyses revealed high concentrations of (-)-α-thujone in the leaves of T. occidentalis individuals from both the Shenyang and Kunming populations. However, (-)-α-thujone (0.18 ± 0.17 µg/g) was only detected in the rhizosphere soil to a distance of 0.5 m from the plant. CONCLUSIONS: Taken together, our results suggest that the phytotoxic effects and antifungal activities of the EOs and (-)-α-thujone in T. occidentalis certainly increased the adaptability of this plant to the environment. Nevertheless, low concentrations of released (-)-α-thujone indicated that reasonable distance of T. occidentalis with other plant species will impair the effects of allelochemical of T. occidentalis.


Asunto(s)
Aceites Volátiles/metabolismo , Thuja/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Antifúngicos/metabolismo , Monoterpenos Bicíclicos/análisis , China , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/análisis , Hojas de la Planta/química
12.
J Oleo Sci ; 69(7): 759-765, 2020 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-32522943

RESUMEN

The current investigation reports the chemical composition of volatile organic compounds emitted from the different aerial organs of two populations of Salvia dominica L. from Jordan collected from Mediterranean and Irano-Turanian bio-geographical zones. Oxygenated monoterpenes dominated the emission profiles of most organs from the two populations but with variable qualitative and quantitative differences. Mediterranean samples contained higher content of oxygenated monoterpenes (stems: 88.37%, leaves 89.95%, pre-flowering buds 67.14%, fully opened flowers 79.43%, sepals 90.93% and petals 92.25%) as compared to those from Irano-Turanian origin (range 39.85% to 75.06%). trans-Sabinene hydrate dominated the emission profiles of all organs from Irano-Turanian zone (range 38.54% to 73.24%) in addition to the stem, sepal and petal samples from the Mediterranean zone (51.37% to 86.98%). The other organs from the Mediterranean zone were dominated by α-terpenyl acetate (27.66-54.87%). Cluster and Principle Component statistical analysis classified the two populations into two clusters based on their origin. The current study evidenced the different VOCs composition in the two populations, that was mainly related to climatic and environmental conditions and suggested the presence of two ecotypes of S. dominica L.in Jordan.


Asunto(s)
Monoterpenos Bicíclicos/metabolismo , Monoterpenos/metabolismo , Salvia/metabolismo , Compuestos Orgánicos Volátiles/metabolismo , Monoterpenos Bicíclicos/análisis , Clima , Ambiente , Jordania , Monoterpenos/análisis , Oxidación-Reducción , Salvia/anatomía & histología , Salvia/clasificación
13.
Biochem Biophys Res Commun ; 528(4): 726-731, 2020 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-32517869

RESUMEN

Aromatherapy has been widely used as complementary and alternative medicine to reduce pain and induce sleep. However, the scientific evidence regarding the biological effects of odor is scarce and the underlying molecular mechanisms have not been clarified. We treated worms with contactless S-(-)- and R-(+)-α-pinene and analyzed heat stress tolerance. Odor stimulation induced motility recovery after incubation at 35 °C for 4 h. This increase in heat stress tolerance was not present in odr-3 mutants and daf-16 mutants. S-(-)- and R-(+)-α-pinene expanded health span and increased fat accumulation. Moreover, S-(-)- and R-(+)-α-pinene modulated the expression of 84 and 54 genes, respectively. These results show that α-pinene odor stimulation is related to stress tolerance, lipid metabolism, and health span via some specific signaling pathways. This study may provide a potential target for antiaging and disease prevention.


Asunto(s)
Monoterpenos Bicíclicos/farmacología , Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/efectos de los fármacos , Factores de Transcripción Forkhead/metabolismo , Odorantes , Termotolerancia/efectos de los fármacos , Animales , Aromaterapia , Monoterpenos Bicíclicos/análisis , Caenorhabditis elegans/fisiología , Respuesta al Choque Térmico/efectos de los fármacos , Odorantes/análisis
14.
J Chromatogr A ; 1623: 461190, 2020 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-32505284

RESUMEN

Basic principles are introduced for implementing discovery-based analysis with automated quantification of data obtained using comprehensive three-dimensional gas chromatography with flame ionization detection (GC3-FID). The GC3-FID instrument employs dynamic pressure gradient modulation, providing full modulation (100% duty cycle) with a fast modulation period (PM) of 100 ms. Specifically, tile-based Fisher-ratio analysis, previously developed for comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS), is adapted and applied for GC3-FID where the third chromatographic dimension (3D) is treated as the "spectral" dimension. To evaluate the instrumental platform and software implementation, ten "non-native" compounds were spiked into a ninety-component base mixture to create two classes with a concentration ratio of two for the spiked analyte compounds. The Fisher ratio software identified 95 locations of potential interest (i.e., hits), with all ten spiked analytes discovered within the top fourteen hits. All 95 hits were quantified by a novel signal ratio (S-ratio) algorithm portion of the F-ratio software, which determines the time-dependent S-ratio of the 3D chromatograms from one class to another, thus providing relative quantification. The average S-ratio for spiked analytes was 1.94 ± 0.14 mean absolute error (close to the nominal concentration ratio of two), and 1.06 ± 0.16 mean absolute error for unspiked (i.e., matrix) components. The appearance of the S-ratio as a function of 3D retention time in the GC3 dataset, referred to as an S-ratiogram, provides indication of peak purity for each hit. The unique shape of the S-ratiogram for hit 1, α-pinene, suggested likely 3D overlap. Parallel factor analysis (PARAFAC) decomposition of the hit location confirmed that overlap was occurring and successfully decomposed α-pinene from a highly overlapped (3Rs = 0.1) matrix interferent.


Asunto(s)
Cromatografía de Gases/métodos , Ionización de Llama , Algoritmos , Monoterpenos Bicíclicos/análisis , Análisis Factorial , Espectrometría de Masas/métodos , Programas Informáticos
15.
Chemosphere ; 256: 127071, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32470730

RESUMEN

The measurements of a monoterpene (α-pinene) were performed by the PTR-TOF-MS instrument at an urban site of India from mid-January to March 2014. The daytime concentration increased from 0.15 ppb in the second-half of January to 0.40 ppb in the second-half of March. Both the nighttime and daytime ratios of α-pinene/benzene in the second-half of March were 2-3 times higher their respective values from mid-January to first-half of February. The ratios of α-pinene/benzene increased from ∼0.27 ppb ppb-1 at lower temperatures to ∼0.51 ppb ppb-1 at higher temperatures indicating the increase of biogenic emissions in March. The concentration of α-pinene exhibited exponential decline with wind speed, but the rate of decrease in February was about twice that for March. The nighttime ratios of α-pinene/isoprene were greater than those measured in the daytime, suggesting temperature-dependent biogenic emissions of α-pinene. From mid-January to March, the increase of ∼53% in the biogenic contributions of α-pinene were associated with the change in meteorological conditions. Our analysis suggests that the combined effect of the northwest wind flow and higher air temperatures in March favored the emissions of BVOCs from local vegetation. The exceptionally high concentrations of α-pinene up to 6 ppb were measured during the Holi bonfire festival. This is the first study reporting the change in α-pinene during winter-summer transition over India. In the urban regions of developing countries, high emissions of BVOCs from vegetation and of NOx from anthropogenic sources can act as a source of ozone.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monoterpenos Bicíclicos/análisis , Monitoreo del Ambiente , Benceno/análisis , Butadienos , Hemiterpenos , India , Meteorología , Monoterpenos/análisis , Ozono/análisis , Estaciones del Año , Temperatura , Viento
16.
Artículo en Inglés | MEDLINE | ID: mdl-32447252

RESUMEN

Terpenes and terpenoids are dominant fragrances in the essential oils of many economically important fruits and vegetables. Hence, content and variation are important factors in the evaluation and common perception of food quality. Sabinene, ß-pinene, α-thujone and ß-thujone are examples of such compounds found in the different species of Sage. Sabinene and ß-pinene are spicy compounds much used by the fragrance industry while the two thujones are highly toxic. Here, we report a rapid method for quantification of these compounds in the essential oil of Sage. The total analytical time is approx. 7,5 min in contrast to approx. 30 min for similar gas chromatographic methods. The analytical method had a linear range of 28-342 mg L-1 for the different compounds, with an analytical precision of 0,6-0,9% for standards. Correlation coefficients were 0,9993-1,0000. The Limit of Detection of all compounds were 0,02-0,9 mg L-1 and the Limit of Quantification were 0,08-3,0 mg L-1. The technique was used for quantification of the compounds in seven commercial essential Sage oils and in a pilot study of the effect of ozone on the terpenes and terpenoids in fresh Sage leaves. Large variation was observed between the different commercial samples, of which some were thujone dominant and some did not have any content of thujone at all. Treatment of fresh Sage leaves with ozone caused degradation of the terpenes sabinene and ß-pinene whereas the terpenoids α/ß-thujone were more resistant to degradation.


Asunto(s)
Monoterpenos Bicíclicos/análisis , Cromatografía de Gases/métodos , Aceites Volátiles/química , Aceites de Plantas/química , Salvia officinalis , Límite de Detección , Modelos Lineales , Reproducibilidad de los Resultados
17.
Molecules ; 25(4)2020 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-32069801

RESUMEN

Inhalation of vapors from a hot tea of Eucalyptus camaldulensis Dehnh. leaves is considered by Iraqi-Kurdistan people an effective spasmolytic and antipyretic remedy for the treatment of respiratory diseases. The constituents of volatile fractions isolated by hydrodistillation from dried leaves of the plant collected in Kurdistan were determined by GC-FID and GC-MS analyses. More than 90% components were identified. The most abundant constituents were 1,8-cineole, p-cymene, α-pinene, terpinen-4-ol, aromadendrene, and α-terpineol. The different volatile fractions induced relaxation on rat isolated aortic and tracheal rings in concentration-dependent manner. These effects appeared to be due to a complex interaction between various terpenoid components rather than being only due to the main oil constituent, 1,8-cineole. The KCa channel and the NO pathway were not significantly involved in the relaxation mechanism, while Ca2+ channels played a major role in the spasmolytic effects.


Asunto(s)
Eucalyptus/química , Extractos Vegetales/química , Hojas de la Planta/química , Animales , Aorta/efectos de los fármacos , Monoterpenos Bicíclicos/análisis , Dióxido de Carbono/química , Cromatografía de Gases , Monoterpenos Ciclohexánicos/análisis , Cimenos/análisis , Eucaliptol/análisis , Cromatografía de Gases y Espectrometría de Masas , Irak , Masculino , Extractos Vegetales/farmacología , Ratas , Terpenos/análisis , Tráquea/efectos de los fármacos
18.
Nat Prod Res ; 34(3): 441-444, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30600707

RESUMEN

The hydro-distilled essential oil from aerial parts of Orthosiphon pallidus Royle, ex Benth (Lamiaceae) was investigated by using gas chromatography equipped with a flame ionisation detector (GC-FID) and gas chromatography coupled with a mass spectrometry (GC-MS). Fifty-two compounds, representing 98.4% of the total oil constituents, were identified. The major constituents were ß-caryophyllene (17.4%) and 7-epi-α-selinene (15.2%). The other minor constituents were terpinolene (6.9%), ß-pinene (6.8%), ß-elemene (5.1%), α-humulene (4.9%), α-copaene (4.8%), epi-cubebol (4.5%) and zonarene (3.9%). The oil was found to be rich in sesquiterpene hydrocarbon type constituents. Lamiaceae[Formula: see text].


Asunto(s)
Aceites Volátiles/análisis , Orthosiphon/química , Monoterpenos Bicíclicos/análisis , Monoterpenos Ciclohexánicos/análisis , Cromatografía de Gases y Espectrometría de Masas , Lamiaceae/química , Sesquiterpenos Monocíclicos/análisis , Aceites Volátiles/química , Sesquiterpenos Policíclicos/análisis , Sesquiterpenos/análisis
19.
Nat Prod Res ; 34(13): 1947-1950, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30689406

RESUMEN

Chemical composition of the headspace volatiles and essential oils isolated from different parts of Ferulago sylvatica was determined by GC and GC/MS analyses. The results showed that headspace volatiles obtained from the aerial parts and roots were similar regarding the number of identified compounds and main components. However, essential oils obtained from different plant organs showed significant differences in chemical composition. Myrcene was the most abundant component of the inflorescences and shoots volatiles, while α-pinene make up over 50% of the root volatiles. Only three components were identified in the root essential oil with 2,3,6-trimethyl benzaldehyde (92.7%) as the main component. In the shoots sample the terpenoid fractions represented 56% of the oil, unevenly distributed between monoterpenoids and sesquiterpenoids with germacrene D (32.5%) recognized as the main constituent. On the other hand, more than 94% of the inflorescences oils were monoterpenoids with myrcene as the most abundant contributor (29.2%).


Asunto(s)
Apiaceae/química , Aceites Volátiles/química , Extractos Vegetales/química , Estructuras de las Plantas/química , Terpenos/análisis , Monoterpenos Acíclicos/análisis , Alquenos/análisis , Monoterpenos Bicíclicos/análisis , Cromatografía de Gases y Espectrometría de Masas , Monoterpenos/análisis , Aceites de Plantas/química , Serbia , Sesquiterpenos/análisis
20.
Nat Prod Res ; 34(23): 3409-3413, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30758988

RESUMEN

Agareratum fastigiatum is a Brazilian medicinal plant used as anti-inflammaroty and for wound healing by the folk medicine. In vitro and in vivo studies involving A. fastigiatum essential oil (EOAF) showed indications of anti-inflammatory activity, however, its effect on membrane integrins involved on cell migration is still unclear. Hence, it was evaluated in the present study the effect of EOAF on CD18 frequency on human lymphocytes. By using gas chromatography/mass spectrometry it was identified 9 compounds on EOAF: α-pinene; ß-pinene; ß-myrcene; d-limonene; ß-ocimene; sesquiterpenes; α-copaene; 4,8-ß-epóxi-caryophyllene; germacrene and bicyclogermacrene. On in vitro tests, 6.25 × 10-3 and 12.5 × 10-3 µL/mL EOAF reduced CD18 frequency on phorbol-12-myristate-13-acetate (PMA)-stimulated lymphocytes. Such cells were obtained from peripheral blood of healthy volunteers, and were treated or not with EOAF. They were stained with fluorescent anti-CD18 monoclonal antibodies, after 24 hours incubation. Our data corroborates previous findings, indicating a possible anti-inflammatory activity of EOAF.


Asunto(s)
Ageratum/química , Antígenos CD18/metabolismo , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Aceites Volátiles/química , Aceites Volátiles/farmacología , Monoterpenos Acíclicos/análisis , Alquenos/análisis , Monoterpenos Bicíclicos/análisis , Cromatografía de Gases y Espectrometría de Masas , Humanos , Limoneno/análisis , Monoterpenos/análisis , Aceites Volátiles/análisis , Plantas Medicinales/química , Sesquiterpenos/análisis , Acetato de Tetradecanoilforbol/farmacología
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