Authors:É. Héthelyi, S. Szarka, É. Lemberkovics, and É. Szőke
Héthelyi, B. É., Galambosi, B., Szarka, S. (2009): Mikkeliben termesztett
kemotaxonok illóolajának GC/MS-, a herba SPME-GC/MS vizsgálata. (GC/MS study of essential oil from
chemotaxons grown in Mikkeli and
Authors:Ágnes Móricz, Szabolcs Szarka, Péter Ott, Dóra Kertesy, Éva Héthelyi, Éva Szőke, and Ernő Tyihák
The isolation and characterization of antibacterial chamomile components were performed by the use of direct bioautography and solid phase microextraction (SPME)-gas chromatography (GC)-mass spectrometry (MS). Four ingredients, active against Vibrio fischeri, were identified as the polyacetylene geometric isomers cisand trans-spiroethers, the coumarin related herniarin, and the sesquiterpene alcohol (−)-alpha-bisabolol.
Authors:P. A. Azar, A. Porgham-Daryasari, M. Saber-Tehrani, and M. Soleimani
In this study, gas chromatography-mass spectrometry (GC-MS) following microwave distillation and solid-phase microextraction (MD-SPME) was developed for the analysis of essential oil compounds in Nepeta crispa. To improve the headspace (HS) method, microwave powers, irradiation times, and SPME fiber coatings were studied. The optimal experiment parameters obtained were 65-μm PDMS/DVB SPME fiber, a microwave power of 400 W, and an irradiation time of 3 min. MD-SPME was compared with headspace solid-phase microextraction (HS-SPME) and conventional hydrodistillation (HD) for the extraction of essential oil compounds in N. crispa. A comparative qualitative and quantitative study on the composition of the oils was carried out. For this, 26 compounds, constituting 98.2% of the oil, were identified in the essential oil by MD-SPME, and 23 compounds, representing 91.3% of the oil, were characterized in the SPME and HD methods; 25 compounds, constituting 94.6% of the oil, were separated and identified. The main compounds identified by all methods were 1,8-cineol, β-bourbonene, α-terpineol, and β-pinene. The relative standard deviation (RSD) values of less than 8% show that the MD-SPME method has good repeatability.
It has been shown that the extraction of essential oils from N. crispa with MD-SPME was better in terms of energy saving, extraction time, plant material, oxygenated fractions, and product quality.
In this study, detection of an obligate aerobic, thermophilic and acidophilic bacterium, the sporeforming Alicyclobacillus acidoterrestris was performed by determination of its specifc metabolite, guaiacol. Since its spores have been shown to resist conventional pasteurization, it has become a potential spoilage concern for fruit and vegetable juices, mainly for apple and orange juices. Detection of guaiacol was carried out by using an NST 3320 type electronic nose, and other methods, such as peroxidase-based enzymatic method with UV-Vis spectrophotometer, SPME-GC-MS technique and an untrained sensory panel were also applied. The results indicated that based on their detection limit the methods can be ordered in the following way: SPME-GC-MS (detection limit: <0.5 ppm)<sensory evaluation (detection limit: 0.5–1 ppm)<spectrophotometric method=electronic nose technique (detection limit: 1.25–2.5 ppm).
Authors:Emil Mincsovics, Péter Ott, Ágnes Alberti, Andrea Böszörményi, Éva Héthelyi, Éva Szőke, Ágnes Kéry, Éva Lemberkovics, and Ágnes Móricz
Bioassay-guided isolation of antibacterial components of chamomile flower methanol extract was performed by overpressured layer chromatography (OPLC) with on-line detection, fractionation combined with sample clean-up in-situ in the adsorbent bed after off-line sample application. The antibacterial effect of the eluted fractions and of those compounds remaining on the adsorbent layer after separation was tested with direct bioautography (DB) against the bioluminescent Pseudomonas savastanoi pv. maculicola and Vibrio fischeri. The fractions with high biological activity were analyzed by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and liquid chromatography and tandem mass spectrometry (LC-MS/MS). Two active uneluted compounds were characterized by off-line OPLC-MS using a thin-layer chromatography (TLC)-MS interface. Mainly, essential oil components, coumarins, flavonoids, phenolic acids, and fatty acids were identified in the active fractions.
Authors:E. Várvölgyi, T. Werum, L. Dénes, J. Soós, G. Szabó, J. Felföldi, G. Esper, and Z. Kovács
Oliveira , R.C.S., Oliveira , L.S., Franca , A.S. & Augusti , R. (2009): Evaluation of the potential of SPME-GC-MS and chemometrics to detect adulteration of ground roasted coffee with roasted barley. J. Food Comp. Anal. , 22 , 257
pheromone of the lesser date moth, Batrachedra amydraula , using autosampling SPME-GC/MS and field bioassays . Chemoecology 23 , 13 – 20 .
Lysandrou , M. , Temerak , S. A. and Sayed , A. A. ( 2010 ): The use of different insect control regimes