Analytical fingerprint and chemometrics as phytochemical composition control tools in food supplement analysis: characterization of raspberry bud preparations of different cultivars

BACKGROUND: The raspberry, Rubus idaeus L., provides several plant parts (as buds) used for food supplements. The aim of this research was to establish a technique for chemical composition control of R. idaeus herbal preparations, using chromatographic methods. These methods allowed us to identify and quantify the main phytochemicals, obtaining a specific phytochemical fingerprint (phytocomplex). Combined with two different chemometric methods - clustering analysis and principal component analysis - the raspberry bud extracts of the different cultivars were efficiently characterized. RESULTS: Rubus idaeus buds were identified as a rich source of anti-inflammatory and antioxidant compounds: organic acids, vitamins and catechins were found to be the most discriminating variables by chemometric techniques to differentiate raspberry cultivars. In particular, catechins (13.25%) and flavonols (8.71%) were the most important polyphenolic classes, followed by cinnamic and benzoic acids. CONCLUSION: This study developed a useful tool for R. idaeus extract phytochemical characterization that could be applied also for differentiation and composition control of other herbal preparations.