South African Journal of Botany, cilt.165, ss.478-493, 2024 (SCI-Expanded)
Thymus species (Lamiaceae), commonly referred to as thyme, have gained popularity due to their utilisation in traditional medicine for various ailments such as gastrointestinal disorders, colds, upper respiratory infections, vomiting, jaundice, oral hygiene and oral ulcers. Nevertheless, a significant number of Thymus species remain unexplored in terms of their bioactivity and phenolic content. In the present study, a thorough chemical analysis of endemic Thymus canoviridis methanol (METC)-water extracts (WETC) and Thymus pubescens var. pubescens methanol (METP)-water extracts (WETP) was carried out by Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry (UPLC-MS/MS). In addition, the inhibitory effect and antioxidant properties of these extracts on the enzymes acetylcholinesterase (AChE), α-glycosidase and carbonic anhydrase II (CA II) were also evaluated. The antioxidant potential was assessed using six assays, namely DPPH, ABTS, DMPD, FRAP, CUPRAC and Fe3+ reducing assays. Our results suggest that the methanol extract from these two plants exhibits a higher level of antioxidant activity. Furthermore, WETP inhibited all enzymes in the best way. According to the UPLC-MS/MS analysis results, rosmarinic acid showed its highest content in METC (18285.55 µg/g extract), WETC (27.98 µg/g extract) and METP (2910.59 µg/g extract), while WETP (69.76 µg/g extract) and the following total amounts of phenolic compounds were METC 20726.55 µg/g extract, METP 5887.20 µg/g extract, WETP 348.98 µg/g extract, WETC 68.56 µg/g extract. It is consistent with the analytical result, total phenolic content, and activity ranking in antioxidant assays. Regard to the results of the molecular docking studies, there is a high binding affinity between the CA II enzyme and cyanidin-3-O-glycoside, between the AChE and keracyanin chloride, and between α-glycosidase enzyme and rosmarinic acid. The extracts were discovered to exhibit various biological activities, such as antioxidant, antidiabetic, anti-Alzheimer's disease, and antiglaucoma properties.