Evaluation of the anti-SARS-CoV-2 properties of essential oils and aromatic extracts

Essential oils and aromatic extracts (oleoresins, absolutes, concretes, resinoids) are often used as food flavorings and constituents of fragrance compositions. The flavor and fragrance industry observed significant growth in the sales of some natural materials during the COVID-19 outbreak. Some companies worldwide are making false claims regarding the effectiveness of their essential oils or blends (or indirectly point toward this conclusion) against coronaviruses, even though the available data on the activity of plant materials against highly pathogenic human coronaviruses are very scarce. Our exploratory study aimed to develop pioneering knowledge and provide the first experimental results on the inhibitory properties of hundreds of flavor and fragrance materials against SARS-CoV-2 main and papain-like proteases and the antiviral potential of the most active protease inhibitors. As essential oils are volatile products, they could provide an interesting therapeutic strategy for subsidiary inhalation in the long term.

Automated summary

Essential oils and aromatic extracts are commonly used in food flavoring and fragrance compositions. During the COVID-19 outbreak, there has been significant growth in the sales of natural materials in the flavor and fragrance industry. Some companies have made false claims about the effectiveness of their essential oils against coronaviruses, despite limited data on the activity of plant materials against highly pathogenic human coronaviruses. Our exploratory study aims to provide pioneering knowledge and experimental results on the inhibitory properties of flavor and fragrance materials against SARS-CoV-2, as well as the antiviral potential of the most effective protease inhibitors. Additionally, essential oils could be a promising therapeutic strategy for long-term subsidiary inhalation.