Green synthesis of AgNPs from Ajwain leaves: Exploring its therapeutic potential for antibacterial, anti-inflammatory, anti-cancerous and antioxidant effects

Green-synthesized silver nanoparticles (AgNPs) using Trachyspermum ammi (ajwain) leaf extract were successfully fabricated. The ajwain AgNPs was characterized by various tools and exhibited a characteristic surface plasmon resonance peak at 350 nm (UV–Vis), confirmed by formation of small (∼29.15 nm) crystalline nanoparticles with face-centered cubic structure by XRD. FTIR identified phenolic O H (3378 cm −1 ), amide C O (1673 cm −1 ), and C H bending (1440 cm −1 ) from plant metabolites capping agents, while zeta potential (−26.6 mV) indicated moderate colloidal stability suitable for bioassays. SEM revealed irregular micro-particulate aggregates with textured morphology. Ajwain AgNPs demonstrated superior bioactivity versus aqueous extract across the concentrations (125, 250, 500 μg). Antibacterial assays against H. pylori and B. aerogenes showed 2.2–2.8 times larger zones (36.36 mm vs 16.06 mm maximum), achieving 77–79% of ampicillin efficacy. Antioxidant capacity by H₂O₂ scavenging assay (82.72% vs 72.25%) and phosphomolybdenum assay (74.01% vs 68.81%), reaching 86–89% of ascorbic acid. Anti-inflammatory potential surpassed extract by 12–15% in protein denaturation test (75.34% vs 66.84%) and proteinase inhibition test (69.95% vs 61.27%), approaching 72–79% diclofenac efficacy. MTT assay on Caco-2 cells confirmed dose-dependent cytotoxicity (IC₅₀ = 349.85 μg/ml), with nanoparticles reducing viability to 25.8% versus extract's 32.1% at 500 μg. These findings validate ajwain AgNPs as multifaceted nano-phytotherapeutics against enteric infections, oxidative stress, inflammation, and colorectal cancer, offering sustainable alternatives to conventional therapeutics.