RESUMO
The aim of this study was to determine the concentration of oleocanthal in olive pomace waste and compare this to its concentration in extra-virgin olive oil (EVOO). The concentration of oleocanthal in freshly pressed EVOO and its subsequent waste was analysed at early, mid and late season harvests. Oleocanthal concentrations were quantified using high-performance liquid chromatography-mass spectrometry. In oil, oleocanthal concentration was as follows: 123.24 ± 6.48 mg kg(-1) in early harvest, 114.20 ± 17.42 mg kg(-1) in mid harvest and 152.22 ± 10.54 mg kg(-1) in late harvest. Its concentration in waste was determined to be: 128.25 ± 11.33 mg kg(-1) in early harvest, 112.15 ± 1.51 mg kg(-1) in mid harvest and 62.35 ± 8.00 mg kg(-1) in late harvest. Overall, olive pomace waste is a valuable source of oleocanthal.
Assuntos
Aldeídos/análise , Fenóis/análise , Óleos de Plantas/química , Resíduos/análise , Aldeídos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Monoterpenos Ciclopentânicos , Espectrometria de Massas , Estrutura Molecular , Azeite de Oliva , Fenóis/isolamento & purificação , Estações do AnoRESUMO
HPLC with acidic potassium permanganate chemiluminescence detection was employed to analyse 17 Cabernet Sauvignon wines across a range of vintages (1971-2003). Partial least squares regression analysis and principal components analysis was used in order to investigate the relationship between wine composition and vintage. Tartaric acid, vanillic acid, catechin, sinapic acid, ethyl gallate, myricetin, procyanadin B and resveratrol were found to be important components in terms of differences between the vintages.
RESUMO
HPLC with UV and acidified potassium permanganate chemiluminescence detection, combined with multivariate data analysis techniques, were used for the geographical classification of some Australian red (Cabernet Sauvignon) and white (Chardonnay) wines from two regions (Coonawarra and Geelong). Identification of the wine constituents prominent in the chromatography was performed by mass spectrometry. Principal components analysis and linear discriminant analysis were used to classify the wines according to region of production. Separation between regions was achieved with both detection systems and key components leading to discrimination of the wines were identified. Using two principal components, linear discriminant analysis with UV detection correctly classified 100% of the Chardonnay wines and, overall 91% of the Cabernet Sauvignon wines. With acidified potassium permanganate chemiluminescence detection, 75% of the Chardonnay wines and 94% of the Cabernet Sauvignon wines were correctly classified using two factors.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Medições Luminescentes/métodos , Espectrofotometria Ultravioleta/métodos , Vinho/análise , Austrália , Cinamatos/análise , Análise Discriminante , Flavonoides/análise , Geografia , Espectrometria de Massas , Análise de Componente Principal , Tartaratos/análise , Vinho/classificaçãoRESUMO
This paper reports an investigation into the temporal stability of aqueous solutions of psilocin and psilocybin reference drug standards over a period of fourteen days. This study was performed using high performance liquid chromatography utilising a (95:5% v/v) methanol: 10 mM ammonium formate, pH 3.5 mobile phase and absorption detection at 269 nm. It was found that the exclusion of light significantly prolonged the useful life of standards, with aqueous solutions of both psilocin and psilocybin being stable over a period of seven days.
Assuntos
Alucinógenos/normas , Psilocibina/normas , Cromatografia Líquida de Alta Pressão , Psilocibina/análogos & derivados , TempoRESUMO
A simple and robust capillary electrophoresis chemiluminescence detection system for the determination of morphine, oripavine and pseudomorphine is described, based upon the reaction of these analytes with acidic potassium permanganate in the presence of sodium polyphosphate. The reagent solution was contained in a quartz detection cell which also held both the capillary and the anode. The resultant chemiluminescence was monitored directly using a photomultiplier tube mounted flush against the base of the detection cell. To ensure that no migration of the permanganate anion occurred, the anode was placed at the detector end whilst the electroosmotic flow was reversed by the addition of hexadimethrine bromide (0.001% m/v) to the electrolyte. The three analytes were separated counter to the electroosmotic flow via their interaction with alpha-cyclodextrin. The methodology realised detection limits (3 x S/N) of 2.5 x 10(-7) M for both morphine and oripavine and 5 x 10(-7) M for pseudomorphine. The relative standard deviations of the migration times and the peak heights for the three analytes ranged from 0.6 up to 0.8% and from 1.5 up to 2.1%, respectively.
Assuntos
Morfina/análise , Entorpecentes/análise , Eletroforese Capilar , Medições Luminescentes , Morfina/química , Derivados da Morfina/análise , Derivados da Morfina/química , Entorpecentes/química , Tebaína/análogos & derivados , Tebaína/análise , Tebaína/químicaRESUMO
A procedure for the determination of morphine in process streams by sequential injection analysis based on the chemiluminescence reaction of morphine with acidic potassium permanganate in the presence of sodium hexametaphosphate is presented. The chemiluminescence emission has been monitored using an in-house detection system which consisted of a fibre optic flowthrough cell and a sensitive, low dark current, photomultiplier tube. The calibration graph (range 2 x 10(-8) to 1 x 10(-4) mol/l) was not linear over the entire range of concentration, with a polynomial equation of best fit of y = 1.0 x 10(15) x(3) - 2.2 x 10(11) x(2) + 1.3 x 10(7) x - 8.3. The calibration function approximates linearity over the concentration range 2.5 x 10(-6) to 3.0 x 10(-5) mol/l where the slope of the log-log plot is 1.09 +/- 0.16. The detection limit was estimated at about 10(-8) mol/l from the response of the lowest calibration standard (2.5 x 10(-8) mol/l) which gave a signal to noise ratio of 3 : 1. Although the structurally related codeine did not interfere significantly the results suggest that this method may be susceptible to matrix effects, dependent on the location of sampling from the process stream.