Chemical profiling by LC-MS/MS and GC-MS and biological activity assessment of different extracts of Portulaca oleracea through in-vitro and in-silico approaches.

In this study, the phenolic compound profile and essential oil composition of Portulaca oleracea L. collected from the Bulancak (Giresun) region of Türkiye were investigated in detail by LC-MS/MS and GC-MS techniques. The obtained data were then correlated with multifaceted biological activity tests and in-silico molecular modelling. In the scope of the study, the anti-diabetic (inhibition of α-amylase and α-glucosidase), anti-inflammatory (inhibition of protein denaturation) and anti-hemolytic effects were evaluated in conjunction with the chemical composition data. The results of the LC-MS/MS analysis indicate that p-coumaric acid is the predominant phenolic, with a concentration of 1228.10 mg/kg. The presence of other phenolics was also detected, including vanillin (5.12 mg/kg), caffeic acid (2.75 mg/kg), sesamol (1.87 mg/kg) and protocatechuic aldehyde (1.75 mg/kg). In the GC-MS analysis, hexahydrofarnesyl acetone was the most abundant component, accounting for 58.89% of the total. Subsequent analysis identified dillapiole (16.80%), myristicin (8.95%), and β-ionone (6.31%) as the active constituents. In the anti-diabetic activity test, the IC50 values for α-amylase inhibition ranged from 352.24 to 623.45 mg/mL, and the strongest effect was observed in the ethanol extract. For the assessment of α-glucosidase inhibition, the IC50 values were observed to range from 146.85 to 339.20 mg/mL, thus indicating a stronger inhibitory effect of α-glucosidase compared to α-amylase. The results of in-silico modelling provided support for the in-vitro data that had been obtained. It was shown that p-coumaric acid can interact strongly with both α-amylase (binding energy: -5.57 kcal/mol; inhibition constant: 83.05 µM) and α-glucosidase (binding energy: -5.84 kcal/mol; inhibition constant: 52.14 µM). Dillapiole demonstrated a noteworthy interaction with α-glucosidase, exhibiting a binding energy of -6.60 kcal/mol and an inhibition constant of 14.59 µM. In the protein denaturation inhibition test, which was used to investigate the anti-inflammatory effect, the highest effect was obtained in the chloroform extract (76.1% inhibition, IC50 = 126 µg/mL). In the AAPH-induced hemolysis test, 200 µg/mL ethanol extract demonstrated a protection level of 65.17%, which was significantly higher than the equivalent dose of ascorbic acid (39.41%). In conclusion, this study demonstrates that the Giresun population of P. oleracea contains different type and levels of bioactive compounds, exhibits versatile biological activity, and could be an important resource for both functional food development and drug discovery. Furthermore, it was demonstrated that the extraction solvents employed (ethanol, chloroform, ethyl acetate, water) have a significant effect on the resulting compound profile and biological activity.