A study from the Autonomous University of Nuevo Leon in Mexico revealed the chemical composition, as well as the antimicrobial and antioxidant activities of orange essential oil. The findings were published in CyTA - Journal of Food.
Aside from orange essential oil, the researchers also evaluated its folded oils and its major component d-limonene.
Based on the results, the amount of d-limonene decreased in folded orange oils (5x, 10x, and 20x), but other compounds such as decanal, linalool, and alpha-terpineol increased.
This meant that d-limonene, despite being a major compound in folded orange oil, did not play a role in determining antioxidant activity.
To determine the antimicrobial activity of orange essential oil against foodborne pathogens, the researchers used disk diffusion method followed by the minimum inhibitory concentration and minimum bactericidal concentration.
They found that the antimicrobial activity of folded orange oil was better than that of orange essential oil and d-limonene. Folded orange oil had higher results in antioxidant assays that other oils studied.
The researchers concluded that folder oils from orange essential oil can be used as a natural food preservative given its antioxidant and antimicrobial effects.
Torres-Alvarez C, González AN, Rodríguez J, Castillo S, Leos-Rivas C, Báez-González JG. CHEMICAL COMPOSITION, ANTIMICROBIAL, AND ANTIOXIDANT ACTIVITIES OF ORANGE ESSENTIAL OIL AND ITS CONCENTRATED OILS. CyTA - Journal of Food. 7 November 2016;15(1):1–7. DOI: 10.1080/19476337.2016.1220021