Secondary Metabolite Profiling of Satureja aintabensis P.H. Davis and Satureja spicigera (K. Koch) Boiss. by LC-HRMS and Evaluation of Antioxidant and Anticholinergic Activities

In this study, phenolic compounds of methanol extracts obtained from the leaves and branches of <i>Satureja aintabensis</i> P.H. Davis and <i>Satureja spicigera</i> (K. Koch) Boiss. species were determined as mg/kg extract using the liquid chromatography high resolution mass spectrometry technique. The in vitro inhibitory effects of these extracts against enzymes associated with neurodegenerative Alzheimer's disease (AD) were also evaluated. The relationship between secondary metabolite structures and biological activities was discussed. The major components of <i>S. aintabensis</i> were determined as hesperidin (6.465% of the extract; 64.65 g/kg), syringic acid (5.964% of the extract; 59.64 g/kg), rosmarinic acid (5.248% of the extract; 52.48 g/kg) and naringenin (0.395% of the extract; 3946.84 mg/kg), while syringic acid (3.081% of the extract; 30.81 g/kg), rosmarinic acid (2.757% of the extract; 27.57 g/kg), hesperidin (1.723% of the extract; 17.23 g/kg), and luteolin-7-<i>O</i>-rutinoside (1.682% of the extract; 16.82 g/kg) were determined in <i>S. spicigera</i>. AChE and BChE enzyme inhibition of the extracts were analyzed. The species showed moderate inhibition against AChE enzyme and low inhibition against BChE enzyme. The antioxidant properties of both plant extracts were evaluated by measuring three radical scavenging capacities and the ability to reduce Fe³⁺, and Cu²⁺ ions. <i>S. aintabensis</i> showed better antioxidant capacity in all methods except DPPH scavaging assay. These data clearly show that both species, especially <i>S. aintabensis</i>, have emerged as a new and important natural source of hesperidin, syringic acid and rosmarinic acid and an antioxidant agent for pharmaceutical and nutraceutical applications.