Eucalyptus Essential Oil Inhibits Cell Infection by SARS-CoV-2 Spike Pseudotyped Lentivirus

Area of Science:

• Virology
• Pharmacology
• Natural Products Chemistry

Background:

• Emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants pose an ongoing global health challenge.
• Development of effective preventive and therapeutic strategies against SARS-CoV-2 is crucial.

Purpose of the Study:

• To investigate the antiviral capacity of eucalyptus essential oil (EEO) and eucalyptol (EOL) against SARS-CoV-2.
• To evaluate EEO and EOL as potential agents for preventing SARS-CoV-2 infection.

Main Methods:

• Cytotoxicity assessment of EEO and EOL using MTT assay.
• Evaluation of antiviral activity against SARS-CoV-2 pseudovirus in hACE2-293T cells via luciferase assay.
• Comparative analysis of EEO and EOL efficacy against vesicular stomatitis virus (VSV) pseudovirus.

Main Results:

• Non-cytotoxic concentrations of EEO and EOL (≤ 0.1%) were identified.
• Both EEO and EOL significantly inhibited SARS-CoV-2 pseudovirus infection with low IC50 values.
• EEO and EOL also demonstrated inhibitory effects on VSV pseudovirus infection, suggesting a Spike-independent mechanism.

Conclusions:

• Eucalyptus essential oil (EEO) and eucalyptol (EOL) exhibit significant antiviral activity against SARS-CoV-2.
• These compounds may offer a novel, cost-effective approach for preventing viral infections, potentially including SARS-CoV-2 variants.
• The findings support the use of aromatherapy with EEO and EOL as a complementary antiviral measure.