Bioactivity and phenolics profle of aqueous and ethyl acetate extracts of Satureja kitaibelii Wierzb. ex Heuf. obtained by ultrasound‑assisted extraction

The aim of the study was to investigate the biological activity and chemical composition of Satureja kitaibelii Wierzb. ex Heuf. LC–PDA/MS analyses for the aqueous extracts (A1-stem, leaves and fowers, A2-leaves and fowers) and ethyl-acetate extracts (E1-stem, leaves and fowers, E2-leaves and fowers) obtained by ultrasound-assisted extraction enabled the identifcation of thirty-four compounds. Quantitative analysis revealed that the aqueous extract obtained from leaves and fowers was the richest in total phenolic acids (65.36 mg/g) and favonoids (21.17 mg/g). The total polyphenol content was the highest in the aqueous extract obtained from leaves and fowers (274± 2.4 mg Gallic Acid equivalents/g). The best antioxidant activity was observed for the same extract using the DPPH (SC50 20 ± 10 µg/mL), ABTS (2.834 ± 0.02 mg Ascorbic Acid/g), FRAP (1.922 ± 0.03 mmol Fe2+/mg), and total reducing power tests (16.4 ± 1.0 mg Ascorbic Acid/g). Both ethyl acetate extracts were the most active against strains of Bacillus cereus and Micrococcus favus (MIC 1.70–1.99 mg/mL and 1.99– 3.41 mg/mL, respectively). They were more efcient against Aspergillus ochraceus (MFC 0.86 mg/mL) and towards HeLa cell lines. All the obtained results implied the good potential of the investigated extracts to be used as efective preservatives and functional ingredients in food products and dietary supplements.