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1.
Biology (Basel) ; 10(7)2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34201481

RESUMEN

When exposed to stressful conditions, plants produce numerous volatile organic compounds (VOCs) that have different biological and environmental functions. VOCs emitted during the rehydration process by the fronds of desiccation tolerant fern Asplenium ceterach L. were investigated. Headspace GC-MS analysis revealed that the volatiles profile of rustyback fern is mainly composed of fatty acid derivatives: isomeric heptadienals (over 25%) and decadienals (over 20%), other linear aldehydes, alcohols, and related compounds. Aerial parts of the rustyback fern do not contain monoterpene-type, sesquiterpene-type, and diterpene-type hydrocarbons or corresponding terpenoids. Online detection of VOCs using proton-transfer reaction mass spectrometry (PTR-MS) showed a significant increase in emission intensity of dominant volatiles during the first hours of the rehydration process. Twelve hours after re-watering, emission of detected volatiles had returned to the basal levels that corresponded to hydrated plants. During the early phase of rehydration malondialdehyde (MDA) content in fronds, as an indicator of membrane damage, decreased rapidly which implies that lipoxygenase activity is not stimulated during the recovery process of rustyback fern.

2.
Comput Med Imaging Graph ; 86: 101796, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33069034

RESUMEN

In tissues containing significant amounts of organised collagen, such as tendons, ligaments, menisci and articular cartilage, MR imaging exhibits a strong signal intensity variation caused by the angle between the collagen fibres and the magnetic field. By obtaining scans at different field orientations it is possible to determine the unknown fibre orientations and to deduce the underlying tissue microstructure. Our previous work demonstrated how this method can detect ligament injuries and maturity-related changes in collagen fibre structures. Practical application in human diagnostics will demand minimisation of scanning time and likely use of open low-field scanners that can allow re-orienting of the main field. This paper analyses the performance of collage fibre estimation for various image SNR values, and in relation to key parameters including number of scanning directions and parameters of the reconstruction algorithm. The analysis involved Monte Carlo simulation studies which provided benchmark performance measures, and studies using MR images of caprine knee samples with increasing levels of synthetic added noise. Tractography plots in the form of streamlines were performed, and an Alignment Index (AI) was employed as a measure of the detected orientation distribution. The results are highly encouraging, showing high accuracy and robustness even for low image SNR values.


Asunto(s)
Cartílago Articular , Cabras , Animales , Cartílago Articular/diagnóstico por imagen , Colágeno , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética
3.
Magn Reson Med ; 82(3): 1041-1054, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31081201

RESUMEN

PURPOSE: To investigate whether magnetic field-related anisotropies of collagen may be correlated with postmortem findings in animal models. METHODS: Optimized scan planning and new MRI data-processing methods were proposed and analyzed using Monte Carlo simulations. Six caprine and 10 canine knees were scanned at various orientations to the main magnetic field. Image intensities in segmented voxels were used to compute the orientation vectors of the collagen fibers. Vector field and tractography plots were computed. The Alignment Index was defined as a measure of orientation distribution. The knees were subsequently assessed by a specialist orthopedic veterinarian, who gave a pathological diagnosis after having dissected and photographed the joints. RESULTS: Using 50% less scans than reported previously can lead to robust calculation of fiber orientations in the presence of noise, with much higher accuracy. The 6 caprine knees were found to range from very immature (< 3 months) to very mature (> 3 years). Mature specimens exhibited significantly more aligned collagen fibers in their patella tendons compared with the immature ones. In 2 of the 10 canine knees scanned, partial cranial caudal ligament tears were identified from MRI and subsequently confirmed with encouragingly high consistency of tractography, Alignment Index, and dissection results. CONCLUSION: This method can be used to detect injury such as partial ligament tears, and to visualize maturity-related changes in the collagen structure of tendons. It can provide the basis for new, noninvasive diagnostic tools in combination with new scanner configurations that allow less-restricted field orientations.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Ligamentos/diagnóstico por imagen , Ligamentos/lesiones , Imagen por Resonancia Magnética/métodos , Animales , Colágeno/química , Perros , Cabras , Miembro Posterior/diagnóstico por imagen
4.
J Food Sci Technol ; 55(8): 2910-2925, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30065400

RESUMEN

Many Eryngium species have been traditionally used as ornamental, edible or medicinal plants. The gas chromatography-flame ionization detector (GC-FID) and gas chromatography-mass spectrometry (GC-MS) analyses have shown that the major compounds in the aerial parts were spathulenol (in E. campestre and E. palmatum oils) and germacrene D (in E. amethystinum oil). The main compounds in the root oil were nonanoic acid, 2,3,4-trimethylbenzaldehyde and octanoic acid for E. campestre, E. amethystinum and E. palmatum, respectively. All the oils expressed the highest potential against Gram-positive bacteria Staphylococcus aureus as well as Gram-negative Klebsiella pneumoniae and Proteus mirabilis. Molecular docking analysis was used for determining a potential antibacterial activity mechanism of compounds present in the essential oils. Molecular docking confirmed that the binding affinity of spathulenol to the active site of tyrosyl-tRNA synthetase was the highest among the tested dominant compounds. Regarding the total phenolic content (determined by the Folin-Ciocalteu assay) and flavonoid content (evaluated using aluminum nitrate nonahydrate), the highest amount was found in the ethyl acetate extract of E. palmatum. The results of DPPH and ABTS assay indicated that the highest antioxidant activity was present in the water extract of E. amethystinum. Extracts of the aerial parts presented as minimum inhibitory concentration (MIC) expressed the activity in the range 0.004-20.00 mg/mL, with the highest activity exhibited by the acetone and ethyl acetate extracts against Proteus mirabilis. The obtained results suggest that Eryngium species may be considered a beneficial native source of the compounds with antioxidant and antimicrobial properties.

5.
J Agric Food Chem ; 65(50): 10933-10949, 2017 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-29129053

RESUMEN

The essential oil, different extracts, and isolated compounds of Angelica pancicii Vandas (Apiaceae) were investigated for the first time. The GC-FID and GC-MS analyses revealed sesquiterpenoids as the main constituents of A. pancicii essential oil of aerial parts with bornyl acetate (8.08%), n-octanol (5.82%), kessane (4.26%), and ß-selinene (4.26%) as the main constituents. Analysis of methanol extracts, using an HPLC-DAD/ESI-ToF-MS system, showed a total of 52 compounds in the aerial parts and 53 in the roots, indicating coumarins as the main constituents. In addition, new chromone (1) and six known furanocoumarins (2-7) were isolated from the roots and structurally elucidated by combined spectroscopic methods. The aerial part extracts exhibited higher polyphenolic contents and antioxidant activity evaluated by three radical scavenging assays. Using a microwell dilution method, the strongest antibacterial activity profiles were determined for ethanol and methanol root extracts (minimum bactericidal concentrations (MBCs) = 0.25-3.00 mg/mL), which were comparable to the activity of streptomycin (MBCs = 0.34-1.24 mg/mL), while the strongest antibacterial compound of A. pancicii was oxypeucedanin hydrate (MBCs = 0.50-8.00 mg/mL). Antifungal potential was in moderate extent, and the highest activity was obtained for root methanol extract (minimum fungicidal concentrations (MFCs) = 4.00-14.00 mg/mL). Tested sub-minimum inhibitory concentrations (subMICs) of the extracts and isolated compounds inhibited selected Pseudomonas aeruginosa PAO1 virulence determinants. The most reduced growth of P. aeruginosa colony was in the presence of isolated oxypeucedanin. Ethanol (17.36-46.98%) and methanol (34.54-52.43%) root extracts showed higher anti-biofilm activity compared to streptomycin (49.40-88.36%) and ampicillin (56.46-92.16%).


Asunto(s)
Angelica/química , Antibacterianos/química , Antibacterianos/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Percepción de Quorum/efectos de los fármacos , Antibacterianos/aislamiento & purificación , Antifúngicos/química , Antifúngicos/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , Hongos/efectos de los fármacos , Hongos/fisiología , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Componentes Aéreos de las Plantas/química , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas/química , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología
6.
Chem Biodivers ; 14(12)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28865183

RESUMEN

Composition of tocopherols, tocotrienols, carotenoids, fatty acids, as well as hydrophilic and lipophilic antioxidant activities, were determined in seeds of two Salvia species and oils obtained from them. Both seeds contained a large amount of oil (around 20%) rich in polyunsaturated fatty acids. While Salvia officinalis seed oil can be classified as oleic-linoleic oil, the predominant fatty acid in Salvia sclarea was α-linolenic acid (around 54%). Among tocols, the main isomers in both seeds and oils were γ-tocopherol, followed by α-tocopherol. Concerning carotenoids, their concentration was around 0.75 mg/100 g of seeds and 0.16 mg/100 g of oils, with a predominance of lutein. Oil and seeds of S. officinalis exhibited higher antioxidant potential compared to S. sclarea investigated samples which could be attributed to higher content of total vitamin E and carotenoids. This study provides results that enables use of two Salvia species as new alternative sources of vegetable oils.


Asunto(s)
Antioxidantes/química , Aceites Volátiles/química , Salvia/metabolismo , Antioxidantes/análisis , Carotenoides/análisis , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/análisis , Salvia/química , Salvia officinalis/química , Salvia officinalis/metabolismo , Semillas/química , Semillas/metabolismo , alfa-Tocoferol/análisis
7.
Chem Biodivers ; 14(8)2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28477421

RESUMEN

Comparative analysis of terpene diversity and differentiation of relict pines Pinus heldreichii, P. nigra, and P. peuce from the central Balkans was performed at the population level. Multivariate statistical analyses showed that the composition of needle terpenes reflects clear divergence among the pine species from different subgenera: P. peuce (subgenus Strobus) vs. P. nigra and P. heldreichii (subgenus Pinus). In addition, despite the described morphological similarities and the fact that P. nigra and P. heldreichii may spontaneously hybridize, our results indicated differentiation of their populations naturally growing in the same area. In accordance with recently proposed concept of 'flavonic evolution' in the genus Pinus, we assumed that the terpene profile of soft pine P. peuce, defined by high amounts of six monoterpenes, is more basal than those of hard pines P. nigra and P. heldreichii, which were characterized by high content levels of mainly sesquiterpenes. In order to establish precise positions of P. heldreichii, P. nigra and P. peuce within the taxonomic and phylogenetic tree, as well as develop suitable conservation strategies and future breeding efforts, it is necessary to perform additional morphological, biochemical, and genetic studies.


Asunto(s)
Pinus/química , Terpenos/química , Análisis por Conglomerados , Análisis Discriminante , Cromatografía de Gases y Espectrometría de Masas , Filogenia , Pinus/clasificación , Pinus/metabolismo , Análisis de Componente Principal , Especificidad de la Especie , Terpenos/análisis
8.
J Med Entomol ; 54(4): 957-963, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28407077

RESUMEN

Nepeta essential oil (Neo; catnip) and its major component, nepetalactone, have long been known to repel insects including mosquitoes. However, the neural mechanisms through which these repellents are detected by mosquitoes, including the yellow fever mosquito Aedes aegypti (L.), an important vector of Zika virus, were poorly understood. Here we show that Neo volatiles activate olfactory receptor neurons within the basiconic sensilla on the maxillary palps of female Ae. aegypti. A gustatory receptor neuron sensitive to the feeding deterrent quinine and housed within sensilla on the labella of females was activated by both Neo and nepetalactone. Activity of a second gustatory receptor neuron sensitive to the feeding stimulant sucrose was suppressed by both repellents. Our results provide neural pathways for the reported spatial repellency and feeding deterrence of these repellents. A better understanding of the neural input through which female mosquitoes make decisions to feed will facilitate design of new repellents and management strategies involving their use.


Asunto(s)
Aedes/efectos de los fármacos , Ciclopentanos/farmacología , Repelentes de Insectos/farmacología , Nepeta/química , Aceites Volátiles/farmacología , Neuronas Receptoras Olfatorias/efectos de los fármacos , Pironas/farmacología , Sensilos/efectos de los fármacos , Aedes/fisiología , Animales , Monoterpenos Ciclopentánicos , Femenino , Maxilar/efectos de los fármacos , Maxilar/fisiología , Neuronas Receptoras Olfatorias/fisiología , Sensilos/fisiología
9.
Food Funct ; 7(9): 4061-4074, 2016 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-27713984

RESUMEN

GC-FID and GC-MS were used to determine the chemical composition of the essential oil of the aerial parts of Heracleum orphanidis Boiss. Also, the HPLC-DAD/ESI-ToF-MS profile of the methanol extracts of aerial parts and roots was determined. The main components of the essential oil were n-octanol, octyl hexanoate and n-octyl acetate, while coumarins were the most prevalent compounds in methanol extracts. An evaluation of antioxidant activity showed that the methanol and aqueous extracts of the aerial parts had the highest potential. In terms of antimicrobial activity determined by microdilution assays, the essential oil and methanol extract of the roots showed the greatest effectiveness. The colonies of Pseudomonas aeruginosa PAO1 treated with H. orphanidis samples produced less toxic pyocyanin, showed lower twitching and flagella mobility and biofilm formatting was reduced. The analyses in this study showed the considerable biological potential of H. orphanidis considering free radicals and various pathogenic strains, including the wild type of P. aeruginosa.


Asunto(s)
Conservantes de Alimentos/metabolismo , Heracleum/química , Aceites Volátiles/metabolismo , Componentes Aéreos de las Plantas/química , Extractos Vegetales/metabolismo , Raíces de Plantas/química , Pseudomonas aeruginosa/fisiología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Antibacterianos/metabolismo , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Antioxidantes/metabolismo , Biopelículas/crecimiento & desarrollo , Etnofarmacología , Ionización de Llama , Conservantes de Alimentos/química , Conservantes de Alimentos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Medicina Tradicional , Metanol/química , Viabilidad Microbiana , Estructura Molecular , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificación , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Pseudomonas aeruginosa/crecimiento & desarrollo , Pseudomonas aeruginosa/aislamiento & purificación , Percepción de Quorum , República de Macedonia del Norte , Solventes/química , Espectrometría de Masa por Ionización de Electrospray , Vida Silvestre
10.
J Magn Reson ; 271: 60-7, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27552556

RESUMEN

A novel design of open permanent magnet is presented, in which the magnetic field is oriented parallel to the planes of its poles. The paper describes the methods whereby such a magnet can be designed with a field homogeneity suitable for Magnetic Resonance Imaging (MRI). Its primary purpose is to take advantage of the Magic Angle effect in MRI of human extremities, particularly the knee joint, by being capable of rotating the direction of the main magnetic field B0 about two orthogonal axes around a stationary subject and achieve all possible angulations. The magnet comprises a parallel pair of identical profiled arrays of permanent magnets backed by a flat steel yoke such that access in lateral directions is practical. The paper describes the detailed optimization procedure from a target 150mm DSV to the achievement of a measured uniform field over a 130mm DSV. Actual performance data of the manufactured magnet, including shimming and a sample image, is presented. The overall magnet system mounting mechanism is presented, including two orthogonal axes of rotation of the magnet about its isocentre.

11.
Chem Biodivers ; 13(7): 943-53, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27286568

RESUMEN

The composition of the essential oil of the twigs and needles of Taxus baccata L. from three natural populations in Serbia has been determined by GC/MS analysis. Of the 91 detected compounds, 87 were identified. The most abundant compound classes were aliphatic alcohols, terpenes, aliphatic hydrocarbons, and aliphatic aldehydes, which together comprised ca. 86.92% of the total oil composition. The dominant constituents were oct-1-en-3-ol (23.48%), (3Z)-hex-3-en-1-ol (11.46%; aliphatic alcohols), and myrtenol (11.38%; oxygenated monoterpene). The PCA of 22 selected compounds revealed differentiations of populations based on geographic distribution. The CA showed that Populations I and II from the Dinaric Alps were similar, and that Population III from the Balkan mountain system was distinct. This was the first investigation of interpopulation variability of T. baccata populations based on essential oil composition. The results of this study were compared with those of previous studies concerning volatile compounds produced by Taxus species. The results indicate that the essential oil content of T. baccata populations from this study is unique, mostly resembling the population from southeast Serbia.


Asunto(s)
Aceites Volátiles/análisis , Taxus/química , Cromatografía de Gases y Espectrometría de Masas , Serbia
12.
Chem Biodivers ; 13(2): 181-7, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26880430

RESUMEN

The composition and variability of the terpenes and their derivatives isolated from the needles of a representative pool of 114 adult trees originating from four natural populations of dwarf mountain pine (Pinus mugo Turra) from the Julian Alps were investigated by GC-FID and GC/MS analyses. In total, 54 of the 57 detected essential-oil components were identified. Among the different compound classes present in the essential oils, the chief constituents belonged to the monoterpenes, comprising an average content of 79.67% of the total oil composition (74.80% of monoterpene hydrocarbons and 4.87% of oxygenated monoterpenes). Sesquiterpenes were present in smaller amounts (average content of 19.02%), out of which 16.39% were sesquiterpene hydrocarbons and 2.62% oxygenated sesquiterpenes. The most abundant components in the needle essential oils were the monoterpenes δ-car-3-ene, ß-phellandrene, α-pinene, ß-myrcene, and ß-pinene and the sesquiterpene ß-caryophyllene. From the total data set of 57 detected compounds, 40 were selected for principal-component analysis (PCA), discriminant analysis (DA), and cluster analysis (CA). The overlap tendency of the four populations suggested by PCA, was as well observed by DA. CA also demonstrated similarity among the populations, which was the highest between Populations I and II.


Asunto(s)
Aceites Volátiles/química , Pinus/química , Monoterpenos Acíclicos , Monoterpenos Bicíclicos , Compuestos Bicíclicos con Puentes/análisis , Análisis por Conglomerados , Monoterpenos Ciclohexánicos , Ciclohexenos/análisis , Cromatografía de Gases y Espectrometría de Masas , Monoterpenos/análisis , Sesquiterpenos Policíclicos , Análisis de Componente Principal , Sesquiterpenos/análisis
13.
Chem Biodivers ; 12(2): 295-308, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25676511

RESUMEN

The needle-terpene profiles of two natural Pinus heldreichii populations from Mts. Osljak and Galicica (Scardo-Pindic mountain system) were analyzed. Among the 68 detected compounds, 66 were identified. The dominant constituents were germacrene D (28.7%), limonene (27.1%), and α-pinene (16.2%). ß-Caryophyllene (6.9%), ß-pinene (5.2%), ß-myrcene (2.3%), pimaric acid (2.0%), α-humulene (1.2%), and seven additional components were found to be present in medium-to-high amounts (0.5-10%). Although the general needle-terpene profile of the population from Galicica was similar to those of the populations from Lovcen, Zeletin, Bjelasica, and Zlatibor-Pester (belonging to the Dinaric Alps), the principle-component analysis (PCA) of seven terpenes (ß-myrcene, limonene, ß-elemene, ß-caryophyllene, α-humulene, δ-cadinene, and germacrene D-4-ol) in 121 tree samples suggested a partial divergence in the needle-terpene profiles between the populations from the Scardo-Pindic mountain system and the Dinaric Alps. According to previously reported data, the P. heldreichii samples from the Balkan-Rhodope mountains lack ß-caryophyllene and germacrene D, but contain γ-muurolene in their terpene profile. Differences in the terpene composition between populations growing in the three above-mentioned mountain systems were compared and discussed.


Asunto(s)
Aceites Volátiles/química , Pinus/química , Alelos , Peninsula Balcánica , Cromatografía de Gases y Espectrometría de Masas , Frecuencia de los Genes , Genotipo , Aceites Volátiles/análisis , Pinus/genética , Pinus/metabolismo , Análisis de Componente Principal , Terpenos/análisis
14.
MAGMA ; 28(1): 33-48, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24802620

RESUMEN

OBJECT: A new method for 3D localization of N fiducial markers from 1D projections is presented and analysed. It applies to semi-active markers and active markers using a single receiver channel. MATERIALS AND METHODS: The novel algorithm computes candidate points using peaks in three optimally selected projections and removes fictitious points by verifying detected peaks in additional projections. Computational complexity was significantly reduced by avoiding cluster analysis, while higher accuracy was achieved by using optimal projections and by applying Gaussian interpolation in peak detection. Computational time, accuracy and robustness were analysed through Monte Carlo simulations and experiments. The method was employed in a prototype MRI guided prostate biopsy system and used in preclinical experiments. RESULTS: The computational time for 6 markers was better than 2 ms, an improvement of up to 100 times, compared to the method by Flask et al. (J Magn Reson Imaging 14(5):617-627, 2001). Experimental maximum localization error was lower than 0.3 mm; standard deviation was 0.06 mm. Targeting error was about 1 mm. Tracking update rate was about 10 Hz. CONCLUSION: The proposed method is particularly suitable in systems requiring any of the following: high frame rate, tracking of three or more markers, data filtering or interleaving.


Asunto(s)
Algoritmos , Marcadores Fiduciales , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética Intervencional/instrumentación , Imagen por Resonancia Magnética Intervencional/métodos , Humanos , Aumento de la Imagen/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Nat Prod Commun ; 9(6): 859-62, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25115100

RESUMEN

Seasonal variations in the composition of the essential oils obtained from the same individual (of the same genotype) of Lavandula angustifolia cultivated in Belgrade were determined by GC and GC/MS. The main constituents were 1,8-cineole (7.1-48.4%), linalool (0.1-38.7%), bomeol (10.9-27.7%), beta-phellandrene (0.5-21.2%) and camphor (1.5-15.8%). Cluster analysis showed that the 21 samples collected each month during the vegetation cycle were separable into three main clades with different compositions of essential oils. In the shoots with flowers, inflorescences and fruits of clade I, linalool is dominant, in the young leaves before flowering and old leaves of clade II, 1,8-cineole is dominant. In the young and incompletely developed leaves of clade III, beta-phellandrene is dominant. The composition of the essential oils of lavender depended on the plant part and the stage of development.


Asunto(s)
Lavandula/química , Aceites Volátiles/química , Aceites de Plantas/química , Estaciones del Año
16.
Nat Prod Commun ; 9(5): 731-5, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-25026735

RESUMEN

GC and GC/MS analyses of the methanol extracts obtained from the aerial parts of six Acinos Miller species from Serbia and Montenegro were performed. Seventy-four constituents, accounting for 84.9-99.0% of the total composition of the extracts, were identified. The common feature of the A. suaveolens, A. majoranifolius and A. alpinus methanol extracts was the high content of monoterpenes, while the common feature of the A. graveolens, A. arvensis and A. hungaricus methanol extracts was the prevalence of sesquiterpenes. The total flavonoids, polyphenols and tannins content, as well as antioxidant activity (FRAP and DPPH assay) of the methanolic extracts were investigated. The highest antioxidant activity was observed in the extract of A. alpinus which had high levels of all polyphenol classes examined. A disk diffusion method was used for the evaluation of the antimicrobial activities of the extracts against a panel of microorganisms (bacteria: Bacillus subtilis, Clostridium pyogenes, Enterococcus sp., Micrococcus flavus, Sarcina lutea, Staphylococcus aureus, Klebsiella pneumoniae, Proteus vulgaris, Pseudomonas aeruginosa, Salmonella enteritidis and Escherichia coli; fungi: Aspergillus niger, Candida albicans and Saccharomyces cerevisiae). The preliminary bioassay results indicated that the methanol extract of A. alpinus could be a possible source of antioxidant and antimicrobial compounds.


Asunto(s)
Antiinfecciosos/farmacología , Antioxidantes/farmacología , Lamiaceae/química , Extractos Vegetales/farmacología , Cromatografía de Gases y Espectrometría de Masas , Extractos Vegetales/análisis
17.
Chem Biodivers ; 11(6): 934-48, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24934679

RESUMEN

The needle-terpene profiles of two natural Pinus peuce populations from the Scardo-Pindic mountain system (Mt. Osljak and Mt. Pelister) were analyzed. Among the 90 detected compounds, 87 were identified. The dominant constituents were α-pinene (45.5%), germacrene D (11.1%), ß-pinene (10.8%), and camphene (10.3%). The following eight additional components were found to be present in medium-to-high amounts (0.5-10%): bornyl acetate (5.0%), ß-phellandrene (3.4%), ß-caryophyllene (2.9%), ß-myrcene (0.9%), germacrene D-4-ol (0.9%), tricyclene (0.7%), (E)-hex-2-enal (0.7%), and bicyclogermacrene (0.6%). Although the general needle-terpene profiles of the populations from Mt. Osljak and Mt. Pelister were found to be similar to those of the populations from Zeletin, Sjekirica, and Mokra Gora (Dinaric Alps), principle component analysis (PCA) of eight terpenes (α-pinene, ß-myrcene, α-terpinolene, bornyl acetate, α-terpinyl acetate, ß-caryophyllene, trans-ß-farnesene, and germacrene D) in 139 tree samples suggested a divergence between the two population groups, i.e., the samples from the Scardo-Pindic mountain system and those from the Dinaric Alps. Genetic analysis of the ß-pinene content demonstrated a partial divergence between the two geographical groups. The profiles of both population groups differed from those published for populations from the Balkan-Rhodope mountains system (literature results), which were characterized by high contents of bornyl acetate and citronellol (Greek populations) or δ-car-3-ene (Bulgarian populations).


Asunto(s)
Productos Biológicos/aislamiento & purificación , Aceites Volátiles/aislamiento & purificación , Pinus/química , Hojas de la Planta/química , Productos Biológicos/química , Aceites Volátiles/química
18.
Chem Biodivers ; 11(1): 101-14, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24443430

RESUMEN

To identify how many chemotypes of Salvia officinalis exist in Montenegro, the chemical composition of the essential oils of 12 wild-growing populations was determined by GC-FID and GC/MS analyses. Among the 40 identified constituents, the most abundant were cis-thujone (16.98-40.35%), camphor (12.75-35.37%), 1,8-cineol (6.40-12.06%), trans-thujone (1.5-10.35%), camphene (2.26-9.97%), borneol (0.97-8.81%), viridiflorol (3.46-7.8%), limonene (1.8-6.47%), α-pinene (1.59-5.46%), and α-humulene (1.77-5.02%). The composition of the essential oils under study did not meet the ISO 9909 requirements, while the oils of populations P02-P04, P09, and P10 complied with the German Drug Codex. A few of the main essential-oil constituents appeared to be highly intercorrelated. Strong positive correlations were observed between α-pinene and camphene, camphene and camphor, as well as between cis-thujone and trans-thujone. Strong negative correlations were evidenced between cis-thujone and α-pinene, cis-thujone and champhene, cis-thujone and camphor, as well as between trans-thujone and camphene. Multivariate analyses allowed the grouping of the populations into three distinct chemotypes, i.e., Chemotype A, rich in total thujones, Chemotype B, with intermediate contents of thujones, α-pinene, camphene, and camphor and high borneol contents, and Chemotype C, rich in camphor, camphene, and α-pinene. The chemotypes did not significantly differ in the total essential-oil content and the cis/trans-thujone ratio.


Asunto(s)
Aceites Volátiles/química , Salvia officinalis/química , Montenegro , Análisis Multivariante , Aceites Volátiles/aislamiento & purificación
19.
Nat Prod Commun ; 8(1): 131-4, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23472478

RESUMEN

Seasonal variations in the composition of the essential oils obtained from rosemary plants of the same genotype cultivated in Belgrade were determined by GC and GC/MS. The main constituents were camphor (18.2 - 28.1%), 1,8-cineole (6.4-18.0%), alpha-pinene (9.7-13.5%), borneol (4.4-9.5%), camphene (5.1-8.7%), beta-pinene (2.1-8.1%), beta-phellandrene (4.6-6.5%), myrcene (3.4-5.9%) and bornyl acetate (0.2-7.9%). Cluster analysis showed that 16 samples that had been collected each month during the vegetative cycle can be separated into three main clades with different compositions of essential oils. In the shoots with fruits ('fruits' - Clade I) and shoots with developed leaves ('old shoots' - Clade III) camphor is dominant. In shoots with young and incompletely developed leaves ('young shoot' - Clade II) camphor and 1,8-cineole had almost the same concentration. The fact that the same genotype during the growing seasons can synthesize oils that are so different that they can be classified as different chemotypes confirms the opinion that the chemical composition of essential oils sometimes critically depends on the time of collection. Also, for the definition of chemotypes it is not enough to base this on a chemical analysis of an oil from one phenophase only.


Asunto(s)
Aceites Volátiles/química , Rosmarinus/química , Análisis por Conglomerados , Estaciones del Año
20.
Chem Biodivers ; 10(1): 157-65, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23341215

RESUMEN

Currant seeds, a by-product of juice production, are recognized as a valuable source of oil rich in polyunsaturated fatty acids. We have evaluated 28 currant varieties for their oil content and fatty-acid composition. The oil content in the seeds ranged from 18.2-27.7%, and no statistical difference between varieties of different fruit color were recorded. Furthermore, the estimated oil yields in the field production ranged from 26.4-212.4 kg/ha. The GC and GC/MS chemical profiles of the seed oils extracted from all examined varieties were common for currants. Linoleic acid (LA) was the major component, with contents ranging from 32.7-46.9% of total fatty acids, followed by α-linolenic acid (ALA; 2.9-32.0 %), oleic acid (OA; 9.8-19.9%), γ-linolenic acid (GLA; 3.3-18.5%), palmitic acid (PA; 4.4-8.1%), stearidonic acid (SDA; 2.2-4.7%), and stearic acid (SA; 1.2-2.4%). Quantitative differences in the fatty-acid profiles between varieties of different fruit color were observed. Blackcurrant varieties showed significantly higher contents of LA, GLA, and PA than red and white currant varieties, whereas significantly higher amounts of ALA and OL were detected in the red and white varieties. Cluster analysis based on the chemical oil profiles joined the blackcurrants in one group, while most of the red and white cultivars joined in a second group at the same linkage distance.


Asunto(s)
Ácidos Grasos/análisis , Cromatografía de Gases y Espectrometría de Masas , Ribes/química , Análisis por Conglomerados , Aceites de Plantas/química , Semillas/química
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