Purification and Characterization of a Flavone 7-O-Glucoside-Specific Glucosidase from Ligulate Florets of Chamomilla recutita

Flavone content and glucosidase activity were analyzed in various species of the genera Chamomilla, Matricaria, and Anthemis, especially during the development of the chamomile flower heads. The accumulation profile of flavonoids and the increase in enzyme activity were similar during ontogenesis. The accumulation of apigenin derivatives in closely related species was always linked to the occurrence of a catabolic β-glucosidase in the respective plant organ. The flavone-glucoside-cleaving β-glucosidase (FGG) from the ligulate florets of chamomile was purified to electro- phoretic homogeneity by the following procedure: ammonium sulphate fractionation, anion exchange on Mono Q, hydrophobic interaction chromatography on Bio-Gel TSK Phenyl-5-PW, and gel filtration on Superose 12