Viola Odorata Extracts: Phytochemical Profiling, Antioxidant Capacity, Enzyme Inhibition, and COX‐2/NOS‐2‐Mediated Anti‐Inflammatory Effects

ABSTRACT In the present study, the phytochemical and bio‐pharmacological effects of the species Viola odorata were explored. Different polarity extracts, namely water and methanol were assayed for their content in phenolic compounds, enzyme inhibition and scavenging/reducing properties. Additionally, through a validated ex vivo model of colon inflammation, the effects of water and methanol extracts were assayed on Escherichia coli lipopolysaccharide (LPS)‐induced up‐regulation of both cyclooxygenase‐2 (COX‐2) and inducible nitric oxide synthase (NOS‐2) gene expression. The results of the study indicate that methanol extract was the richest in terms of total phenols (37.26 mg GAE/g) and flavonoids (56.90 mg RE/g). Indeed, the methanol extract was the most effective as antiradical (DPPH: 24.91 mg TE/g and ABTS: 66.62 mg TE/g) but also as enzyme inhibitor toward cholinesterases (AChE: 3.23 mg GALAE/g and BChE: 5.02 mg GALAE/g), tyrosinase (133.29 mg KAE/g), glucosidase (0.27 mmol ACAE/g), and amylase (0.82 mmol ACAE/g). Transcription factors regulating NOS2 and COX‐2 were used to construct a regulatory network, and five major phytochemicals were screened for target prediction. Selected proteins were subjected to molecular docking, revealing strong interactions between kaempferol‐3‐O‐glucoside and rutin with BChE, NF‐κB, and STAT3. The V. odorata extracts were also effective in blunting the LPS‐induced gene expression of both COX‐2 and NOS‐2 ; thus, confirming enzyme inhibition effects, anti‐inflammatory and antioxidant properties. The results suggest that this species is a valuable source of bioactive compounds for developing health‐promoting applications.