Antidiabetic and antioxidant properties of <i>Paeonia mascula</i> L.: <i>In vitro</i> and <i>in vivo</i> studies, and phytochemical analysis

The medicinal plant Paeonia mascula L. is commonly used in Anatolian folk medicine for its antidiabetic properties. This study aimed to investigate the in vitro alpha-glucosidase enzyme inhibition effect, in vivo antidiabetic, and antioxidant activities of extracts obtained from P. mascula. The in vivo studies were conducted on diabetic rats induced with streptozotocin. The ethyl acetate and n-butanol extracts showed the highest efficacy in both in vitro and in vivo experiments, reducing AST, ALT, and MDA levels while increasing GSH and SOD activities in rats. In total, seven compounds were isolated from both extracts, and their structures were identified using spectroscopic methods such as 1D and 2D NMR and Mass Spectrometry. The in vitro alpha-glucosidase inhibition assay on purified compounds revealed that 1,2,3,4,6-penta-O-galloyl-beta-D-glucose was the most effective compound. These findings support the traditional use of P. mascula as an antidiabetic agent.