Comparative analysis of the phytochemical and physicochemical properties of herbal-infused oils

Abstract

Infused oils with plant extracts are well-known for diverse applications, particularly for their therapeutic and cosmetic purposes; herbal oil infusion enhances the bioactive and physicochemical properties of oils, influencing their suitability for cosmetic and dietary applications. This study evaluates the phytochemical and physicochemical properties of herbal infused oils to determine their stability and potential uses. The infused oils were prepared using selected medicinal plants: turmeric, lemon, neem, carrot, and acalypha, with olive oil as the carrier. Phytochemical screening was conducted to identify bioactive compounds, while physicochemical parameters such as acid value (AV), saponification value (SV), iodine value (IV), peroxide value (PV), and ester value (EV) were assessed following standard analytical procedures. Phytochemical screening revealed terpenoids in all infused oils, while alkaloids, anthraquinones, and steroids were present in specific samples. Tannins, flavonoids, glycosides, and phenols were not detected. Physicochemical analysis showed significant (p<0.05) alterations in oil properties after herbal infusion. AV ranged from 0.14–11.56 mg KOH/g; SV: 3.99–234.05 mg KOH/g, IV: 5.50–57.77 g/100g, PV: 0.68–2.15 mEq O₂/Kg, and EV: 3.85–222.49 mg KOH/g. Lemon-infused oil exhibited the highest acid, saponification, iodine, and ester values, suggesting increased hydrolysis and ester formation, while peroxide values remained low across all samples, indicating good oxidative stability. These findings suggest that infused herbal oils exhibit enhanced bioactive properties with varying stability profiles. While some, like lemon-infused oil, may require refinement before ingestion, others closely resemble the carrier oil, making them suitable for both cosmetic and dietary applications.