ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

α-Glucosidase inhibitors from the aerial part of Thymus fedtschenkoi: isolation, kinetic and molecular docking study

Armin Mohammadi-Liri, Hamed Parsa-Khankandi, Ali Dehnoee, Somayeh Mojtabavi, Mohammad Ali Faramarzi, and Mohammad-Reza Delnavazi

Department of Pharmacognosy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran

E-mail: delnavazi@tums.ac.ir

Received: 16 May 2022  Accepted: 21 September 2022

Abstract:

Thymus fedtschenkoi Ronniger from Lamiaceae family is an endemic Iranian plant and used as traditional remedy by local people. The present study, evaluated ɑ-glucosidase inhibitory potentials of T. fedtschenkoi fractions and its compounds. The aerial part of T. fedtschenkoi was extracted with methanol/water and fractioned by n-hexane, chloroform, and n-butanol solvents, successively. The n-butanol fraction with the highest α-glucosidase inhibitory effect was further investigated with open column chromatography. The structures of isolated compounds were elucidated by ¹H-NMR and ¹³C-NMR spectral analyses. In addition, antidiabetic potentials of the fractions and the isolated compounds were assessed through an in vitro ɑ-glucosidase inhibitory test and kinetic and molecular docking studies were done for the isolated compounds. Eight phenolic compounds including 3, 4-di-O-feruloyl quinic acid (1), luteolin-7-O-rutinoside (2), luteolin (3), rosmarinic acid methyl ester (4), rosmarinic acid (5), apigenin-7-O-glucoside (6), luteolin-7-O-glucuronide (7), and luteolin-7-O-glucoside (8) were isolated. According to the results, compound 5 was the most potent α-glucosidase inhibitor with IC₅₀ value of 43.38 ± 0.05 μM which was about 17 times lower than the IC₅₀ value of the acarbose as reference compound (750.0 ± 1.0 μM). The present study showed a good potency for the n-butanol fraction of T. fedtschenkoi and its compounds to inhibit α-glucosidase enzyme.

Keywords: Thymus fedtschenkoi; ɑ-Glucosidase; Phenolic compounds; Diabetes

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-022-02511-7

Chemical Papers 77 (1) 571–581 (2023)