Food-to-food fortification is an emerging technique to enrich the micronutrients in foods. Pertaining to this technique, noodles could also be fortified with natural fortificants. In this study, marjoram leaf powder (MLP) at a level of 2–10% was used as a natural fortificant to produce fortified rice noodles (FRNs) through an extrusion process. The MLP addition caused a significant increase in the iron, calcium, protein, and fiber in the FRNs. The noodles had a lower whiteness index than unfortified noodles but had a similar water absorption index. The water solubility index increased significantly due to the higher water retention ability of MLP. A rheological study showed a minimal effect of fortification on the gelling strength of the FRNs at lower levels. The microstructural studies found incremental cracks, which facilitated a lower cooking time and hardness but had an insignificant effect on the cooked noodle texture. Fortification improved the total phenolic content, antioxidant capacity, and total flavonoid content. However, no significant changes in bonds were observed, but a reduction in the noodles’ crystallinity could be seen. The sensory analysis of the noodles reflected a higher acceptability of the 2–4% MLP fortified samples compared to the others. Overall, the MLP addition improved the nutritional content, antioxidant activity, and the cooking time but slightly affected the rheological, textural, and color properties of the noodles.

Cerium oxide (CeO₂) nanoparticles were successfully synthesized via a green synthesis route using Tinospora cordifolia leaf extract as a natural reducing, capping, and stabilizing agent. The synthesized nanoparticles were evaluated for their antioxidant activity and corrosion inhibition performance toward mild steel in acidic media. X-ray diffraction (XRD) analysis confirmed the formation of nanocrystalline CeO₂ with a cubic fluorite crystal structure, while Fourier transform infrared (FTIR) spectroscopy revealed the presence of phytochemical functional groups responsible for nanoparticle stabilization and surface functionalization. Morphological analysis indicated clustered nanoparticle structures composed of nanoscale crystallites, whereas dynamic light scattering (DLS) measurements showed larger hydrodynamic diameters due to particle aggregation in aqueous suspension. The influence of synthesis parameters, including pH, temperature, reaction time, and extract concentration, on nanoparticle formation and stability was also investigated. The corrosion inhibition performance of the synthesized CeO₂ nanoparticles was assessed using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and gravimetric weight-loss measurements. The nanoparticles exhibited concentration-dependent inhibition behavior, achieving a maximum corrosion protection efficiency of 82.5%. EIS results revealed enlarged Nyquist semicircles and increased charge transfer resistance, confirming the formation of a protective surface film on mild steel. Weight-loss studies demonstrated inhibition efficiencies of 23.5% after 24 h and 64.7% after 48 h of immersion. Furthermore, DPPH and ABTS radical scavenging assays confirmed significant antioxidant activity, with the methanolic extract exhibiting superior performance. The results demonstrate that T. cordifolia-mediated CeO₂ nanoparticles possess effective antioxidant and mixed-type corrosion inhibition properties through adsorption-driven surface interactions, highlighting their potential as sustainable multifunctional materials for corrosion protection applications.