Phytochemical Profiling and Bioactivity of Celtis caucasica: Antioxidant, Antidiabetic, Anticholinesterase, and Anti-inflammatory Potential

This study evaluates the phytochemical composition and biological activities of the ethanol extract of Celtis caucasica leaves. Gas Chromatography-Mass Spectrometry (GC-MS) identified sixteen bioactive compounds in the ethanol extract of C. caucasica (ETCC), including 4-O-Methylmannose, Guaifenesin, Hexadecanoic acid derivatives, and Phytol, while the chloroform fraction of C. caucasica (CHFCC) contained twenty compounds, notably Phthalic acid di(2-propylpentyl) ester (11.94%) and Octadec-9-enoic acid (11.76%), known for their antioxidant, anti-inflammatory, and neuroprotective properties. Fourier-transform infrared (FT-IR) spectroscopy revealed diverse functional groups in ETCC and strong aromatic peaks with metal-organic complexes in CHFCC. Biological evaluations showed CHFCC had the highest acetylcholinesterase (AChE, 86.44%, IC₅₀ = 13.2 µg/mL) and butyrylcholinesterase (BChE, 92.67%, IC₅₀ = 9.66 µg/mL) inhibition, as well as potent α-glucosidase (88.61%, IC₅₀ = 11.99 µg/mL) and α-amylase inhibition (91.36%, IC₅₀ = 4.22 µg/mL), indicating strong antidiabetic potential. CHFCC also exhibited the highest COX-2 inhibition (88.61%), while the n-hexane fraction (NHFCC) showed the strongest 5-LOX inhibition (88.88%). Antioxidant assays revealed CHFCC had the highest radical scavenging activity (IC₅₀ = 77.24 µg/mL for DPPH and 60.67 µg/mL for ABTS), though lower than ascorbic acid (IC₅₀ = 2.81 µg/mL and 4.6 µg/mL, respectively). These findings highlight C. caucasica as a promising source of bioactive compounds with therapeutic potential.