Exploring citrus waste's potential as an antioxidant, antibacterial, and anti-corrosion agent

Abstract

Citrus reticulata Blanco essential oil was extracted using hydrodistillation, and its chemical profile was analyzed via GC/MS to give limonene as the major component (81.90 %). C. reticulata demonstrated remarkable antioxidant potential in DPPH (1,1-diphenyl-2-picrylhydrazyl) with in IC₅₀ (2.01 ± 0.01 mg/mL), ABTS (bleaching assay) (3.47 ± 0.02 mg/mL), and FRAP (iron reduction) (4.71 ± 0.43 mg/mL) assays, surpassing pure limonene. A synergistic effect was a key feature. In antibacterial tests, C. reticulata exhibited significant activity with a minimum inhibitory concentration (MIC) ranging from 12.5 to 25 µL/mL against four various bacteria (Staphylococcus aureus, Bacillus subtilis, Proteus mirabilis and Escherichia coli). Moreover, C. reticulata displayed impressive anti-corrosion capabilities, achieving up to 92.5 % protection at 1000 ppm using PDP, and 93.1 % using EIS and 90.1 % using WL. Langmuir adsorption isotherm analysis supported inhibitor adsorption, and potentiodynamic polarization curves confirmed its mixed-type action. These findings highlight C. reticulata's promise as a natural antioxidant, antimicrobial, and anti-corrosion agent.