Physicochemical properties, chemical composition, and bioactivity of orange (Citrus sinensis) peel essential oil

Abstract

Orange (Citrus sinensis) peel essential oil (CsEO) is used extensively in pharmaceuticals, cosmetics, and food preservation because of its bioactive qualities and aroma. Nevertheless, different extraction techniques and environmental factors affect its chemical makeup and antioxidant capacity. In order to evaluate the potential uses of CsEO, this study examined its physicochemical characteristics, chemical makeup, and bioactivity. The values of CsEO were 3.561 mg KOH.g-¹ for acid, 8.392 mg KOH.g-¹ for saponification, and 4.831 mg KOH.g-¹ for ester. According to GC-MS analysis, the main component was D-limonene (86.96%), which was followed by α-pinene (5.15%) and β-myrcene (4.69%). The IC₅₀ values for antioxidant assays were 78.47 mg.ml^-1 (ABTS) and 96.69 mg.ml^-1 (DPPH), indicating weaker radical scavenging activity than Vitamin C. Antibacterial tests revealed inhibition zones of 14.16–20.82 mm, demonstrating moderate antimicrobial properties. These findings confirm the consistency of CsEO’s physicochemical properties and chemical profile across studies. While CsEO exhibits moderate antioxidant activity, further research is needed to enhance its bioactivity and optimize extraction methods for industrial applications.