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Using high-performance liquid chromatography/mass spectrometry, leaf and petal phenolic profiles of four rose (Rosa) species (R. canina, R. glauca, R. rubiginosa, R. sempervirens) traditionally used for medicinal purposes and three modern rose cultivars (Rosarium Uetersen, Ulrich Brunner Fils, Schwanensee) were determined. An abundance of phenolic constituents was identified: seven different anthocyanins and 31 flavonols in petals; 30 flavonols, 14 phenolic acids, and their derivatives; 15 flavanols; and 20 hydrolysable tannins in leaves. Additionally, petal color was measured with a colorimeter and regression analysis indicated a strong correlation between color parameter a* and total anthocyanin content. The content and composition of phenolic compounds varied significantly among species and cultivars and plant organs investigated. Distinct differences in the distribution of leaf phenolic compounds were observed, especially between Rosa species and modern rose cultivars. In general, leaves of analyzed species were richer in content of most phenolic groups and individual components compared with cultivars. Multivariate statistical analysis clustered the investigated species and cultivars into three distinct groups. Among species, leaves of R. canina stood out with their high and varied phenolic content. Conversely, leaves of the susceptible cultivar Schwanensee appeared most dissimilar as a result of their low levels of phenolic constituents.

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The aim of this study was to evaluate the effect of fast and slow freezing and frozen storage on the metabolite content of six blackberry cultivars. The content of metabolites determined with HPLC RI/PDA-MS in stored blackberries was compared with the initial content of the fruit. During frozen storage of fruits a loss of vitamin C up to 80% has been recorded along with changes of color values, which shifted to blue and yellow hues. The color changes were accompanied with increased pH levels and content of anthocyanins. Most of the phenolic groups, sugars, and organic acids showed a better extraction after storage, especially in the slow freezing treatment due to a higher degree of tissue damage by freezing. The 'Thornless Evergreen' cultivar was especially rich in sugars, vitamin C, and phenolic compounds, but the highest levels of anthocyanins were determined in 'Loch Ness' cultivar.

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