Using In Vitro and In Silico Analysis to Investigate the Chemical Profile and Biological Properties of Polygonum...

The present study investigates the chemical profile and biological activities of Polygonum istanbulicum M. Keskin, a species endemic to Turkey, aiming to explore its potential applications in pharmacology. We assessed its phenolic and flavonoid content by employing ethyl acetate, methanol, and water as extraction solvents. The methanol extract demonstrated the highest concentrations of these compounds, with liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-MS-qTOF) analysis identifying a wide range of bioactive substances, such as derivatives of quercetin and myricetin. Antioxidant capacity was evaluated using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), cupric-reducing antioxidant capacity (CUPRAC), ferric-reducing antioxidant power (FRAP), and phosphomolybdenum assays, with the methanol extract showing the most potent activity (DPPH: 892.22 mg Trolox equivalent (TE)/g; ABTS: 916.21 mg TE/g; CUPRAC: 1082.69 mg TE/g; FRAP: 915.05 mg TE/g). Enzyme inhibition assays highlighted the efficacy of P. istanbulicum extracts against key enzymes, with potential implications for managing Alzheimer's disease, hyperpigmentation, and type 2 diabetes. Cytotoxicity tests against various cancer cell lines showed notable activity, particularly with the aqueous extract on the HGC-27 cell line (IC₅₀: 29.21 µg/mL), indicating potential for targeted anti-cancer therapy. Molecular docking and molecular dynamics simulations further supported the binding affinities of quercetin and myricetin derivatives to cancer-related proteins, suggesting significant therapeutic potential. This study underscores the value of P. istanbulicum as a source of bioactive compounds with applications in antioxidant, anti-cancer, and enzyme-inhibitory treatments.