Antioxidant and acetylcholinesterase inhibitor activity of polar extracts obtained from Thymus cilicicus

The Lamiaceae family comprises a large number of aromatic plant species with notable medicinal, culinary, and cosmetic applications. Within this family, the genus Thymus widely used in Turkish folk medicine. Thymus cilicicus, has been also used in traditional practices in the form of herbal teas, aromatic waters, and essential oils for the treatment of ailments such as toothache, stomach discomfort, respiratory disorders, diabetes, hypertension, and the common cold. Previous studies have reported antioxidant, antimicrobial, antidiabetic, cytotoxic, and acetylcholinesterase (AChE) inhibitory properties in T. cilicicus extracts obtained with organic solvents. These activities are mainly associated with the presence of phenolic compounds. However, existing literature has not yet addressed the biological activity and chemical composition of extracts obtained through traditional preparation methods such as infusion or maceration. Present study investigates antioxidant capacity such as 1,1-diphenyl-2-picrylhydrazyl radical scavenging (DPPH), ferric reducing antioxidant potency (FRAP) and cupric reducing antioxidant capacity (CUPRAC) along with AChE inhibitory activities of T. cilicicus extracts (ethanol maceration, water maceration, and infusion). Chemical profiles of the extracts were assessed via total phenolic content determination and LC-HRMS. LC-HRMS profiling of tested extracts revealed that major compounds of extracts were fumaric acid, p-coumaric acid, sinapinic acid, and, caffeic acid. Ethanol macerate extract exhibited higher total phenolic content and antioxidant activity in DPPH radical scavenging and CUPRAC assays compared to traditional preparation forms, while infusion extract exhibited highest activity in FRAP assay. None of the tested extract showed AChE inhibition at 100 µg/mL.