Peter Varelis

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Semillon and Shiraz grapes containing ochratoxin A (OA) were obtained by inoculation of bunches on the vine with Aspergillus carbonarius. Citric acid content was greater in the inoculated grapes than in healthy grapes. Samples were collected throughout vinification of these grapes and the OA content was quantified using a stable isotope dilution liquid(More)
An accurate and precise method for the quantification of acrylamide using stable isotope dilution liquid chromatography-tandem mass spectrometry was developed and used to measure acrylamide in coffee and cocoa samples. The sample preparation involved extraction of the analyte and its internal standard, 13C3-acrylamide, into water and subsequent defatting of(More)
Polyphenolic compounds are vasodilators and help to lower the risk of cardiovascular diseases. We hypothesized that a freeze-dried strawberry powder that is rich in polyphenolic compounds would cause an endothelium-dependent relaxation (EDR) through the activation of phosphatidylinositol-3 (PI3)-kinase/protein kinase B (Akt) in rabbit aorta. The powder was(More)
A reliable and accurate method is described for the quantitative analysis of ochratoxin A (OTA) in wine and beer. The method involves the use of disposable non-polar polymeric and aminopropyl solid-phase extraction cartridges to isolate the mycotoxin from alcoholic beverages. Extracts were subsequently analysed using reverse-phase high-performance liquid(More)
The preparation of 4,4'-(1-[(2)H6]methylethylidene)bis-[2,3,5,6-(2)H4]phenol, bisphenol A-d14, was achieved in excellent yield by reaction of [2H6]acetone with [2H6]phenol in the presence of deuterium chloride. The product thus obtained was shown by mass spectroscopy to be a mixture of the 2H14, 2H13 and 2H12 isotopomers in the relative proportions of(More)
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