Biological Activity-Based Assessment of Essential Oil Emulsions

Abstract

The present study was focused on the formulation of clove and cumin essential oil emulsions and their potential for antioxidant and antimicrobial activities. Essential oil extraction was performed using hydrodistillation technique. The % age yield of oils was found to be 8.48 and 1.99% for clove and cumin, respectively. Both oils were subjected to preparation of five emulsions of varying concentrations. The antioxidant activity was measured using DPPH-free radical scavenging assay. The highest scavenging activity was found in case of B1 (25% clove essential oil emulsion) and A1 (25% cumin essential oil emulsion) with IC50 values of 34.40 and 42.66 μg/mL, respectively. Disk diffusion method was applied for screening of antimicrobial activity. Staphylococcus aureus was found to be the most sensitive bacteria with large inhibition zone against B1 (27.66 mm) and A1 (16.66 mm), while among fungal strains, Penicillium notatum was the most sensitive against A1 (10.66 mm) and B2 (9.66 mm). Practical Applications Essential oils are hydrophobic substances which are potential candidates as source of food preservation, pharmaceuticals, alternative medicines and natural therapies in addition to their pharmacological properties like hepatoprotective, carminative, spasmolytic, anticarcinogenic and antiviral effects. Their hydrophobic nature has made them impenetrable in aqueous systems decreasing their intake in the body and ultimately reducing their medicinal benefits. Emulsifiers are responsible for formation of stable emulsions by decreasing the interfacial tension between oil and water phases, making their penetration quite possible in aqueous media.