Chemical Composition of Thyme (Thymus vulgaris) Extracts, Potential Inhibition of SARS-CoV-2 Spike Protein–ACE2 Binding and ACE2 Activity, and Radical Scavenging Capacity
Yuanhang Yao, Monica Whent, Yanfang Li, Zhihao Liu, Pamela Ruth Pehrsson, Jianghao Sun, Pei Chung Chen, Dejian Huang, Thomas T. Y. Wang, Xianli Wu, Liangli Lucy Yu · Journal of Agricultural and Food Chemistry · 2023
Water and ethanol extracts of dried thyme ( Thymus vulgaris ) were analyzed for chemical composition, inhibition of the SARS-CoV-2 spike protein–ACE2 interaction, inhibition of ACE2 activity, and free radical scavenging capacity. Thirty-two compounds were identified in water extract (WE) and 27 were identified in ethanol extract (EE) of thyme through HPLC-MS. The WE (33.3 mg/mL) and EE (3.3 mg/mL) of thyme inhibited the spike protein–ACE2 interaction by 82.6 and 86.4%, respectively. The thyme WE at 5 mg/mL inhibited ACE2 activity by 99%, and the EE at 5 mg/mL inhibited ACE2 by 65.8%. Total phenolics were determined to be 38.9 and 8.8 mg of GAE/g in WE and EE, respectively. The HO • scavenging capacities were 1121.1 and 284.4 μmol of TE/g in WE and EE, respectively. The relative DPPH • scavenging capacities were 126.3 μmol TE/g in WE and 28.2 μmol TE/g in EE. The ABTS •+ scavenging capacities were 267.1 μmol TE/g in WE and 96.7 μmol TE/g in EE. The results suggested that the thyme extract could be potentially used to prevent SARS-CoV-2 infection and mitigate the complications from the infection.