Dülger, GörkemRasgele, Pınar GöçAydın, Emine2023-07-262023-07-2620222757-5195http://doi.org/10.28979/jarnas.1014968https://search.trdizin.gov.tr/yayin/detay/1120791https://hdl.handle.net/20.500.12684/12968It is of great importance to detect the anti-oxidant features of plants, particularly those used for food, pharmacology and medicinal purposes. Stachys thirkei C. Koch belonging to Lamiaceae family is utilised as a medicinal aromatic plant in Turkey. It was aimed to investigate the total phenolic content (TPC), anti-oxidant activity and bio-accessibility of S. thirkei C. Koch. The TPC was evaluated by Folin-Ciocalteu colorimetric proce-dure and antioxidant activity to determine four distinctive assays (ABTS•+, CUPRAC, DPPH• and FRAP). The experimental analysis showed that, the levels of hydrolysable phenolics (1538.99 mg of GAE/100g) approximately three and a half fold higher than extractable phenolics (422.96 mg of GAE/100g). The TPC of S. thirkei C. Koch was determined to be 1961.95 mg of GAE/100g. Moreover, the bio-accessible fractions and phenolic bio-accessibility of S. thirkei C. Koch were found to be 1766.72 ?mol Trolox/g and 90.05 %, respectively. At the same time, the antioxidative bio-accessibility of S. thirkei C. Koch was found to be higher in FRAP method (1164.29 ?mol Trolox/g) and also the bio-accessibility (%) of S. thirkei C. Koch was found to be higher in CUPRAC method (93.41%). Present investigation is the primary report to investigate the bio-accessibility of the extracts from S. thirkei C. Koch. The results of the present may be strong scientific evidence to use S. thirkei C. Koch as a favorable source of antioxidant and the researches can be further extended to investigate whether they exhibit similar activities in in vivo systems.en10.28979/jarnas.1014968info:eu-repo/semantics/openAccessArticle821882001120791