This study assessed how extraction method and tissue source influence yield, composition, and bioactivity of Citrus sinensis (Valencia Late) essential oils (EOs). Hydrodistillation of fruit peel (EO-FPE-CS), cold-pressed peel oil (EO-FPE-CP-CS), and hydrodistillation of whole fruit (EO-WFP-CS) produced significantly different yields (p = 0.027), with EO-FPE-CS highest (≈1.5%) and EO-FPE-CP-CS lowest (≈0.6%). GC–MS profiling showed D-limonene dominance (46.27–92.33%) and higher oxygenated monoterpenes (up to 13.57%) in hydrodistilled oils. Principal component analysis (PC1 = 81.5%, PC2 = 18.5%) separated EO-FPE-CS from EO-FPE-CP-CS, reflecting oxygenate-rich versus hydrocarbon-dominant profiles, while EO-WFP-CS clustered with intermediate volatiles. Antibacterial assays revealed EO-FPE-CS as the most active, inhibiting S. aureus, and S. epidermidis (p < 0.01), with EO-WFP-CS moderately effective and EO-FPE-CP-CS inactive. Antifungal tests against five postharvest pathogens confirmed EO-FPE-CS as most potent, particularly against C. gloeosporioides and G. citri-aurantii. while all three essential oils demonstrated strong DPPH radical scavenging activity.
Fariss et al. (Sun,) studied this question.