Chemical Analysis and Biological Studies of Leaf Extracts of Smallanthus sonchifolius (Poepp.) H. Rob. with an In-silico Assessment of GC-MS Identified Compounds

Smallanthus sonchifolius, from the Asteraceae family, is acknowledged for its therapeutic potential, especially in traditional medicine. This study focuses on the biological activities of its leaf extract, utilizing gas chromatography-mass spectrometry (GC-MS) to identify bioactive phytochemicals and explore antidiabetic properties through molecular docking and pharmacodynamic properties via ADMET predictions. The study involved ultrasonic extraction of shade-dried, powdered leaves using five solvents, followed by screening for phytochemical content and antimicrobial activity against Bacillus subtilis, Escherichia coli, and Candida albicans. The chloroform extract exhibited the highest phenolic content (21.4 mg GAE/g) and flavonoid content (350.87 mg QE/g) with significant TFC in methanol extract (82.05 mg QE/g). In contrast, the methanol extract showed superior antioxidant activity (IC50 = 242.74 μg/mL) and α-amylase inhibition (IC50 = 733.83 μg/mL). Antimicrobial testing showed hexane and methanol extracts were effective against Candida albicans, with inhibition zones comparable to kanamycin. The methanol extract exhibited moderate lethality in the brine shrimp assay with an LC50 value of 216.81 µg/mL. GC-MS analysis identified 16 compounds in hexane extract and 4 in methanol extract. Molecular docking demonstrated strong binding affinities for diazoprogesterone and pentadecafluorooctanoic acid, dodec-2-en-1-yl ester with α-amylase, surpassing reference drug miglitol. In-silico drug-likeness and ADMET predictions indicated potential drug-like properties of the compound diazoprogesterone but further experimental studies are suggested to explore their pharmacological and safety profiles.