Browsing by Author "Wessman, Inka"

Aronia berry consist of possible health promoting anthocyanins of which antioxidative character may have a positive impact to reduce risk factors of cardiovascular diseases. When ingested, anthocyanins decompose to several metabolites of which phenolic acids were the main focus of this research. Phenolic acids can be measured in urine which must be pretreated before further analysis. The aim of the study was to optimize a micro scale solid phase (μSPE) purification method for analysing phenolic metabolites in urine. The method was validated by recovery tests (%). The influence of two acids, formic acid and trifluoroacetic acid, were tested for the recovery (%) of six phenolic compounds: ferulic acid, protochatechuic acid, 3,4-dihydroxyphenylacetic acid, hippuric acid, homovanillic acid and cyanidine-3-glucoside. The method was applied to selected spot urine samples of a clinical research with subjects who had ingested for four weeks 100 ml of aronia juice which contained 1 g of phenolic compounds. Three unknown compounds (A, B and C) were identified as possible derivatives of phenolic acids by UHPLC-MS. The research was part of an EU supported BACCHUSproject. μSPE had a purifying effect with the two acids used having a different influence to the recovery of test compounds. However, there was no clear evidence that either of the acids would be better suited for the purification of the phenolic acids used in this study. Two of the three unknown compounds in randomly selected urine samples were identified as possible derivatives of phenolic acids based on their chromatographic and spectrophotometric characters. Compound A was identified as protocatecuiq acid derivative and compound C was tentatively identified as a derivative of ferulic acid. Compound B instead was not identified because it did not have any typical attributes of phenolic acids.