Attenuation of Free Radicals and Exhibition of Antibacterial Activity by Traditionally used Volatile Oils

摘要

Background: This study aimed to isolate and analyse the essential oils of Eugenia caryophyllus flower buds and Citrus reticulata peels for antioxidant and antibacterial properties. Methods: By using the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radical method and the ferric reducing antioxidant power (FRAP) method, the antioxidant activities of total volatile oil components of both oils were assessed. Agar well diffusion and dilution were used to test antibacterial activity. Results: Optical rotation (0.95 and 1.01), weight per mL (1.03 and 1.06), and refractive index (1.52 and 1.53) were all tested for both oils. The existence of a total of 26 and 28 most important volatile chemical components in oils produced from Eugenia caryophyllus and Citrus reticulata, respectively, was determined by GC-MS chemical analysis of the total volatile component. Retention time in a Gas Chromatography (GC) technique was used to identify the components. The mass spectral database was used to identify the values of oil components. The predominant components were eugenol (77.08) in Eugenia caryophyllus oil and limonene (78.46) in Citrus reticulate oil. Eugenia caryophyllus oil has strong antibacterial action against microorganisms like S. pyrogenes, with a ZOI of 15.90–26.84 mm, followed by oil from Citrus reticulata peels with a ZOI of 14.60– 22.82 mm. Conclusion: The presence of terpenes and phenolics in both essential oils resulted in substantial antioxidant activity. Agar well diffusion and dilution were used to test antibacterial activity. In the concentration range of 5–100 mg/mL, both essential oils demonstrated good bacteriostatic and bactericidal activity against microbial strains.