The main objective of this work is to investigate sustainable ways to corrosion inhibition and photocatalytic applications using natural extracts and green synthesis processes. Specifically, the study investigates at the utilization of an ethanolic extract from the Arum italicum plant as a mild steel corrosion inhibitor in a 1M HCl solution. The extract demonstrated significant corrosion inhibition, with effectiveness influenced by both the concentration of the extract and the temperature of the environment. Polarization studies revealed a maximum inhibition efficiency of 97.85% at 750 ppm, which was corroborated by an efficiency of 97.21% observed through Electrochemical Impedance Spectroscopy (EIS). The results indicate that the extract acts as a mixed-type inhibitor, and its adsorption onto the steel surface follows the Langmuir isotherm, suggesting a physical adsorption mechanism. Beyond corrosion inhibition, the study also explores the green synthesis of silver nanoparticles (Ag NPs) using the Arum italicum extract. These Ag NPs showed outstanding photocatalytic activity, achieving approximately 98% degradation of methylene blue within 150 minutes under sunlight exposure, underscoring their potential for photocatalytic applications in natural light conditions. The antimicrobial efficacy of the synthesized Ag NPs was also assessed, revealing significant inhibition against E. coli, S. aureus, and P. aeruginosa. The Ag NPs were effective against both gram-positive and gram-negative bacteria, with larger inhibition zones observed at higher nanoparticle concentrations, confirming their broad-spectrum antimicrobial properties.