In Vitro and in Silico Studies of Gnaphalium U. Extract: Inhibition of α-amylase and α-glucosidase as a Potential Strategy for Metabolic Syndrome Regulation

A medicinal plant with significant therapeutic promise, Gnaphalium uliginosum was studied for its bioactive components, molecular interactions with α-amylase and α-glucosidase, and inhibitory effects on enzymes that metabolize carbohydrates. High-performance liquid chromatography (HPLC) analysis revealed that the flavonoid tricin and quinic acid derivatives were the main constituents. The anti-inflammatory and antioxidant qualities of these substances are well-known, which adds to their therapeutic value. The enzyme activity decreased in a dose- dependent manner, according to the in vitro α-amylase inhibition experiment. The extract reduced the levels of pancreatic and small intestine starch by 27.2 and 44.5 %, respectively, at the highest dose (100 µL). According to α-glucosidase inhibition experiments, the extract significantly reduced the concentration of glucose, outperforming the reference substance acarbose (44.75 %) with a 46.42 % reduction. Key bioactive chemicals’ binding interactions with α-amylase and α-glucosidase were revealed by molecular docking studies. With binding energies ranging from −7.3 to −9.5 kcal/mol, tricin, 3,5-di-O-caffeoylquinic acid, and 4,5-di-O-caffeoylquinic acid had significant binding affinities. These interactions’ capacity to block enzymes was supported by hydrogen bonding, pi-pistacking, and other stabilizing factors. These results demonstrate Gnaphalium uliginosum’s medicinal potential in the treatment of metabolic diseases like diabetes. The bioactive substances showed strong inhibitory effects on the metabolism of carbohydrates, indicating that they may be used as natural antidiabetic medicines. To confirm these benefits and investigate their potential applications in the treatment of metabolic syndrome, more clinical research is necessary. HIGHLIGHTS Gnaphalium uliginosum extract contains bioactive flavonoids (Tricin) and quinic acid derivatives identified via HPLC. The extract significantly inhibits α-amylase and α-glucosidase activity, reducing starch and glucose metabolism. Molecular docking revealed strong binding of Tricin and caffeoylquinic acids to key digestive enzymes (−7.3 to −9.5 kcal/mol). The extract outperformed acarbose in α-glucosidase inhibition (46.42% vs 44.75%), showing potent antidiabetic potential. Key interactions involved hydrogen bonding and π–π stacking, suggesting high structural compatibility with target enzymes. Demonstrates promising potential for development of natural therapeutics against diabetes and metabolic syndrome. GRAPHICAL ABSTRACT