Bioactivity and phenolics profile of aqueous and ethyl acetate extracts of Satureja kitaibelii Wierzb. ex Heuff

Abstract

Abstract This study aimed at investigating biological activity and chemical composition of Satureja kitaibelii Wierzb. ex Heuff. LC-PDA/MS analyses for the aqueous (A1-ste, leaves and flowers, A2-leves and flowers) and ethyl-acetate (E1-stem, leaves and flowers, E2-leaves and flowers) extracts obrtained by ultrasound-assisted extraction allowed the identification of thirty four compounds. Quantitative analysis revealed that the aqueous extract obtained from leaves and flowers was the richest in total phenolic acids (65.36 mg/g) and flavonoids (21.17 mg/g). Total polyphenol content was the highest in the aqueous extract obtained from leaves and flowers (27±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 flavus (MIC 1.70-1.99 mg/mL and 1.99-3.41 mg/mL, respectively). They were more efficient against Aspergillus ochraceus (MFC 0.86 mg/mL) and towards HeLa cell lines. All obtained results implied the good potential of investigated extracts to be used as an effective preservatives and functional ingredients in food products and dietary supplements.