46 research outputs found
Separation and identification of antibacterial chamomile components using OPLC, bioautography and GC-MS
Components of 50% ethanolic chamomile (Matricaria recutica L.) flower extract, previously found antibacterial in a TLC-bioautographic study, were separated and isolated by the use of on-line OPLC, which consisted of an OPLC 50 BS system, an on-line coupled flow-through UV detector, and a manual fraction collector. The collected peaks were investigated by GC-MS analysis and by TLC re-chromatography with subsequent visualization, performed after use of the vanillin-sulphuric acid reagent, or under UV illumination, or applying bioautographic detection. The main compounds of the collected 11 fractions were identified by GC-MS. The results showed that the antibacterial effect of 50% ethanolic extract of chamomile is ascribable to cis-, trans-spiroethers, and the coumarins like herniarin and umbelliferone
Design and Exploratory Neuropharmacological Evaluation of Novel Thyrotropin-Releasing Hormone Analogs and Their Brain-Targeting Bioprecursor Prodrugs
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Design and Exploratory Neuropharmacological Evaluation of Novel Thyrotropin-Releasing Hormone Analogs and Their Brain-Targeting Bioprecursor Prodrugs
Paper describes novel and metabolically stable analogs derived from thyrotropin-releasing hormone (TRH) by replacing its amino-terminal pyroglutamyl (pGlu) residue with pyridinium-containing moieties
Application of direct bioautography and SPME-GC-MS for the study of antibacterial chamomile ingredients
The isolation and characterization of antibacterial chamomile components were performed by the use of direct bioautography and solid phase microextraction (SPME)-GC-MS. Four ingredients, active against Vibrio fischeri, were identified as the polyacetylene geometric isomers cis- and trans-spiroethers, the coumarin related herniarin, and the sesquiterpene alcohol (-)-alpha-bisabolol
Determination and quantification of 2'-O-fucosyllactose and 3-O-fucosyllactose in human milk by GC-MS as O-trimethylsilyl-oxime derivatives
Human milk oligosaccharides possess various biological functions by protecting the infant from several bacterial and viral infections, modulating the immune system, serving as prebiotics and also contributing to the brain development. Hence, huge effort is underway by manufacturers to produce infant formulas enriched with human milk oligosaccharides which could mimic its diverse biological role the most. For this purpose, quantification of the natural oligosaccharide composition of the human milk is a key task. This study reports a fit for purpose GC-MS method for the quantification of the TMS ether oxime derivatives of 2'-O-fucosyllactose and 3-O-fucosyllactose, the two most abundant trisaccharides in human milk. The EI fragmentation pattern of the linkage isomers is discussed in details, focusing also on specific fragment ions. The GC-MS method with external standard calibration was applied for the monitoring of concentration changes of the trisaccharides throughout the first week of lactation in human milks samples collected from two volunteers. The results showed high concentration of both 2'-FL (4525-6266 μg/mL in donor A and 2694-3551 μg/mL in donor B) and 3-FL (271-441 μg/mL in donor A and 99-208 μg/mL in donor B), while no significant change has been observed throughout the one-week lactation period. The presented GC-MS method can serve as a quality control technique for the infant formulas and also offers an alternative to existing chromatographic methods to investigate HMOs in milk samples. © 2015 Elsevier B.V
GC/MS study of essential oil from Perilla frutescens chemotaxones grown in Mikkeli and SPME-GC/MS study of herb
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Authors' Reply to the Commentary in the journal of Electrophoresis regarding "The effect of simulated space radiation on the N-glycosylation of human immunoglobulin G1" by J.J. Bevelacqua and S.M.J. Mortazavi
SPME-GC/MS identification of aroma compounds in rose flowers
The content and composition of active ingredients and essential oils in medicinal and aromatic plants have been studied for several decades. The volatile compounds in essential oils have been analysed routinely using gas chromatography (GC) since 1966, and with GC coupled to mass spectrometric detection (GC/MS) since 1978.The 13 rose varieties selected for chemical analysis varied for colour, shape and fragrance. The static headspace solid phase microextraction (sHS-SPME) technique recently developed for sample preparation and sample enrichment was used to study the volatile aromatic components.The main volatile compound of a sweet-smelling purple rose was found to be phenyl ethyl alcohol (33-52%). The phenyl ethyl alcohol content of fragrant rose flowers with blackish-purple petals increased continuously from early summer to late autumn (from 17 to 70 %). The dominant aromatic components of the yellow, orange and pink rose flowers were hexanol, hexenyl acetate and benzyl alcohol. Phenyl ethyl alcohol and orcinol dimethyl ether were the main constituents of the fragrant pink and white rose varieties. Methyl vinyl anisol and orcinol dimethyl ether were dominant in rose flowers with beige petals. In summary, it can be concluded that the SPME-GC/MS method is suitable for the characterization of rose varieties and for the chemical analysis of aromatic volatile compounds