The HPLC/DAD Fingerprints and Chemometric Analysis of Flavonoid Extracts from the Selected Sage (Salvia) Species

Abstract

The results of spectrophotometric and HPLC/DAD analysis are discussed, and a comparison is made of selectively extracted flavonoid fractions derived from twenty six sage species belonging to the Salvia genus. The sage samples were harvested in the vegetation seasons 2007, 2008, and 2009. It was a goal of this study to find out which species contain the highest yields of flavonoids (recognized for their free-radical-scavenging activity), as those with the highest yields could be applied in official medicine. It was spectrophotometrically established that the four sage species can be recognized for their highest flavonoid levels, while the HPLC/DAD analysis pointed out to the four other species. The source of the discrepancy between the two evaluation approaches was discussed. Moreover, the HPLC/DAD fingerprints of the flavonoid fraction underwent a chemometric pre-treatment, and then the purified fingerprints were analyzed by means of Principal Component Analysis (PCA) for the differences in the harvesting period. A difference was revealed between the herbs harvested in the 2007 season, and those harvested in 2008 and 2009. The main source of this difference could be the seasonal weather variation and the relatively longest storage period with the plants harvested in 2007.