Inhibitory Effect of L. Extracts on SARS-COV-2 Spike Protein-ACE2 Interaction.

ETHNOPHARMACOLOGICAL RELEVANCE

A catastrophic outbreak of severe acute respiratory syndrome (SARS-CoV-2; Coronavirus disease-19; COVID-19) was first detected in Wuhan, Hubei Province, China, in December 2019. Many experimental and clinical studies have focused on the effectiveness of medicinal plants such as (NS) in combating SARS-CoV-2. In this study, we aimed to evaluate the effect of NS seed extract on SARS-CoV-2 spike protein (S1)-angiotensin-converting enzyme 2 (S-ACE2) interaction.

MATERIALS AND METHODS

NS seed extracts used for the assay were prepared in chloroform, ethanol, and water by Soxhlet extraction and recovered by rotary evaporation. The inhibition percentage of S1-ACE2 interaction was analyzed using ELISA-SARS-CoV-2 S1 Protein-ACE2 Binding Inhibitor Screening Kit. Chemical finger-printing of the extracts was done using RP-HPLC.

RESULTS

Significant concentration-dependent inhibition of the S1-ACE2 interaction was observed with chloroform, ethanol, and water extracts, ranging from 0.01 to 10 mg/ml. The -values for the extracts were as follows: 0.0055, 0.0937, 0.0013, and 0.0003 for chloroform extract; 0.0876, 0.0703, 0.0183, and 0.0071 for ethanol extract; and 0.0915, 0.0312, 0.0006, and 0.0006 for water extract. The 50% inhibitory concentration (IC50) was determined to be 0.132 mg/ml, 0.288 mg/ml, and 4.06 mg/ml for chloroform, ethanol, and water extracts, respectively.

CONCLUSION

The analysis utilizing SARS-CoV2 spike (S1) and ACE2 proteins proved that NS seed extracts have the potential to inhibit the S-ACE2 interaction, which warrants further studies that could lead to potential drug discovery for SARS-CoV2 infection.