LC-MS/MS Analysis and Preliminary Screening of Antidiabetic, Anti-Obesity, and Antioxidant Activities of Selected Turkish Plants.

Type 2 Diabetes mellitus is a complex metabolic disorder often accompanied by oxidative stress, obesity, and dyslipidemia. The limitations of current treatments have increased interest in plant-derived compounds with multitarget potential. This study investigates the in vitro antidiabetic, anti-obesity, antihyperlipidemic, and antioxidant activities of ethanol extracts prepared from selected parts of eight plant species collected from various regions of Türkiye. Ethanol extracts of selected plant parts were evaluated for their inhibitory effects on α-glucosidase, α-amylase, pancreatic lipase, and cholesterol esterase. Antioxidant activities were assessed via DPPH radical scavenging, metal chelating, and ferric reducing power assays. Phytochemical contents were determined using spectrophotometric methods and LC-MS/MS profiling. Among the tested species, Euphorbia macroclada showed the most pronounced in vitro activity, including potent α-glucosidase inhibition (IC50: 37.01 ± 3.37 µg/mL), strong DPPH radical-scavenging activity (89.34% ± 0.15%), and notable cholesterol esterase inhibition (IC50: 79.99 ± 3.48 µg/mL). LC-MS/MS analysis of E. macroclada revealed a phenolic compound profile, with quinic acid and isoquercitrin as major constituents. Olea europaea (branch) and Cichorium intybus also exhibited notable α-glucosidase inhibitor and antioxidant activities. To the best of our knowledge, Silene vulgaris var. macrocarpa is reported here for the first time as a mild pancreatic lipase inhibitor, and the α-glucosidase inhibitory activity of the ethanol extract of E. macroclada is investigated for the first time in this study. Overall, these findings provide preliminary in vitro screening evidence and highlight promising candidates for further investigation; bioactivity-guided fractionation, enzyme kinetic studies, and validation in cellular and/or in vivo models are required before therapeutic conclusions can be drawn. In this study, Euphorbia macroclada was evaluated for its antidiabetic potential, and the results suggest it may be a promising candidate for further investigation.