Relationships between flavonoids and selected elements in infusions of medicinal herbs

Abstract

The aim of the studies was to establish relationships between favonoids and elements important for human health. Therefore, total contents of favonoids and phosphorus were determined by UV/Vis methods, favonoids by HPLC, and Ca, Mg, Fe, Mn, Zn and Cu by FAAS in 68 infusions of medicinal herbs. Total favonoids content in the aqueous extracts were in the range of 0.26-16.40 mg per 100 mL. The mean favonoid contents (in mg per 100 mL of aqueous extract) were 2.24, 2.01, 1.83, 1.88 for rutin, myricetin, quercetin and kaempferol, respectively. The concentrations of Ca, Mg, P were determined in mg per 100 mL, and of Fe, Mn, Zn and Cu in μg per 100 mL. Total content of favonoids was weakly correlated with quercetin (r = 0.41), kaempferol (r = 0.53), Cu (r = 0.43), and Ca (r = -0.30). Statistically significant correlations were also found among Cu, Ca, Mn, Zn and Fe. Cluster analysis grouped the studied herbs based on total favonoids, also four favonoids and essential elements contents, extracted from the whole population of herbs Sambuci fos, Betulae folium, and Sylibi mariani semen. Principal component analysis confirmed these findings and enabled identification of quercetin, kaempferol, Cu and Fe as the factors responsible for differentiation of the studied material.