Hydroalcoholic Extracts of Achillea spp. from Greece: A Study on Phenolic Content and Their Biological Activities

Achillea species are known for their healing properties since ancient times. There is extensive literature on their pharmacological action due to their bioactive compounds. The present study aimed to investigate the antioxidant and antimicrobial effects of hydroalcoholic extracts from the inflorescences and leaves of the species Achillea crithmifolia Waldst. and Kit., A. grandifolia Friv. and A. millefolium L. The phytochemical profiles of all extracts were evaluated both by NMR spectroscopy and LC-MS analysis, and the results were consistent with the spectrophotometrically determined total phenolic (TP: 125.42–191.98 mg/g) and total flavonoid (TF: 47.34–180.02 mg/g) contents. All the extracts were tested for their antioxidant activity using DPPH and ABTS^•+ radical scavenging assay, as well as ferrous ion chelating ability and reducing power tests. All the extracts showed moderate antioxidant activity, compared to the reference substance BHT. Additionally, the antibacterial activity of the extracts was evaluated against major food-borne pathogens, showing moderate antimicrobial effects.