Baicalin can be widely used in inflammatory responses caused by viral infections, such as inhibition of pro-inflammatory cytokines (TNF-α, IL-6) in influenza A (30), inhibition of SARS-CoV-2 RNA-dependent RNA polymerase (RdRp), and angiotensin-converting enzyme 2 (ACE2) activity to prevent SARS-CoV-2 from entering the host cells (31, 32). Here, ACE2 is linked to viral infectious disease.