Chemical composition and bioactivity of Sideritis taurica Stephan ex Wild. (Lamiaceae) leaves: GC/MS analysis, antioxidant and enzyme inhibition activities, and in silico studies

Abstract

Since ancient times, Sideritis taurica and other Sideritis species have been used in traditional medicine in T & uuml;rkiye and beyond for treating a variety of ailments, including coughs, sore throats, gastrointestinal, respiratory, and urogenital disorders, as well as wounds, colds, and flu, and are believed to possess numerous therapeutic properties such as antispasmodic, analgesic, antibacterial, anti-inflammatory, and antioxidant effects. This study aimed to evaluate the enzyme inhibition and antioxidant activities of various extracts from S. taurica leaves collected from Kurucas,ile, Bart & imath;n, T & uuml;rkiye. The extracts were prepared using ethanol, methanol, and hot/cold water extraction methods from leaves that were dried at room temperature and stored in a freezer. Enzyme inhibition activities were assessed against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), alpha-glucosidase, and alpha-amylase, with IC50 values calculated. Antioxidant activities were measured using DPPH, ABTS, and CUPRAC assays. Furthermore, ADME/T (Absorption, Distribution, Metabolism, Excretion, and Toxicity) and molecular docking calculations were performed on the phytochemical components of S. taurica to investigate their effects and interactions with human metabolism. These calculations were performed on a number of proteins, including alpha-amylase protein (PDB ID: 1HNY), AChE protein (PDB ID: 4M0E), and BChE protein (PDB ID: 5NN0). The purpose of these calculations was to investigate the interaction between these substances and human metabolism. The results indicated that the ethanol and methanol extracts exhibited the highest inhibition on AChE and BChE (IC50 values of 73.99 mu g/mL and 5.04 mu g/mL, respectively). The methanol extracts also demonstrated potent inhibition against alpha-glucosidase (IC50 value of 25.81 mu g/mL) and alpha-amylase (IC50 value of 70.42 mu g/mL). Regarding antioxidant activity, the methanol extracts showed the highest radical scavenging activity in the DPPH (87.88 %) and ABTS (99.97 %) tests. Additionally, the methanol extracts stored in the freezer exhibited the best-reducing power in the CUPRAC assay (2.436 +/- 0.1669). These findings underscore the potential of S. taurica as a source of natural antioxidants and enzyme inhibitors, suggesting its applicability in the treatment of neurodegenerative diseases such as Alzheimer's disease. In conclusion, extracts obtained from S. taurica leaves, particularly those derived from room temperature-dried leaves, demonstrate significant enzyme inhibition and antioxidant properties. Also, the findings support the consideration of S. taurica as a natural therapeutic source for neurodegenerative diseases and emphasize for further investigation into its active components and health benefits.