EVALUATION OF THE ANTIMICROBIAL AND ANTIFUNGAL ACTIVITY OF CITRUS PEEL ESSENTIAL OIL EXTRACTED WITH PALMOIL AS A CARRIER
Abstract
This study focused on the evaluation of the antimicrobial activities of citrus peel essential oil extracted using palm oil as carrier oils. The objectives were to determine the efficiency of the oils as carriers, assess their antimicrobial activity, quantify terpenes and terpenoids, and evaluate antioxidant capacity. Phytochemical analysis revealed that palm oil infused with 30% orange peel (PK03) contained the highest terpenes (0.96 ± 0.003) and terpenoids (2.89 ± 0.020), while all infused samples exhibited elevated phenolic and flavonoid contents compared to the control. Antioxidant assays showed significant improvements (p < 0.05), with palm oil infused with 40% orange peel (PK04) recording the highest DPPH scavenging activity (64.86%) though still lower than the synthetic antioxidant BHT (79.50%). Hydroxyl radical scavenging and ferric reducing power were also enhanced in infused samples relative to control, confirming the antioxidant potency of the essential oil. Mineral composition analysis indicated remarkable enrichment, especially in iron (89.58 mg/kg in PK04 vs. 63.90 mg/kg in control), calcium (139.83 mg/kg), magnesium (78.33 mg/kg), zinc (6.28 mg/kg), and potassium (93.27 mg/kg). However, carotenoid content decreased progressively in the infused oils compared to the control (6.03 mg/kg). Antimicrobial screening demonstrated that the infused oils produced larger zones of inhibition against tested microorganisms compared to non-infused controls, suggesting a dose-dependent inhibitory effect. These findings highlight that the incorporation of citrus peel essential oil into palm oils significantly improves their phytochemical profile, enhances antioxidant activity, and confers strong antimicrobial properties. Overall, citrus peel infused oils show promising potential as natural, functional ingredients with possible applications in food preservation, nutraceutical development, and pharmaceutical formulations.
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