Physicochemical Properties, Chemical Composition, and Bioactivity of Orange (Citrus sinensis) Peel Essenstial 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 composition and antioxidant capacity. To evaluate the potential uses of CsEO, this study considered the characteristics just mentioned above. The physicochemical properties of CsEO were determined, including acid value (3.561 mg KOH.g-1), saponification value (8.392 mg KOH.g-1), ester value (4.831 mg KOH.g-1), etc. 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 against Salmonella enteritidis, Escherichia coli, Salmonella enteritidis, and Bacillus cereus, 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.