Malic acid for COVID-19

The fast mutation of COVID-19 viruses still confuses us, and the mRNA vaccines do not inhibit the infection and may protect against the heavy disease. The infection mechanism is described with the protein-protein binding stereo structure; therefore, the infection strength of variants has been estimated from the protein-protein (S-RBD binding with ACE-2) interaction energy values calculated using a molecular mechanics program. The binding strength order was Alfa < Lambda < WT < FE.1 < XBB1.5 < EG.5 ≈ BQ.1 ≈ Alpha+E484K ≈ Omicron XBB.1.16 ≈ Epsilon, Iota < EG.5 < Delta plus ≈ Beta, Kappa B.1.621 ≈ KP.3 ≈ Kappa B.1.617.1 ≈ Delta B.1.517.2 < KP.2 < BA.2.86 ≈ JN.1 ≈ HV.1 ≈ BA.1 < BA.2. The mutation from acidic amino acid to basic amino acid strength the binding. The substitute size of amino acids causes the steric hindrance for the binding. The affinity level supports the infection strength. Various proposed infection inhibitors are quantitatively analyzed. TCA acids and natural polyphenols inhibit the binding of S-RBD to ACE-2. The cocktail dose of known medicines may enhance their performance. The inhibiting multiplication may be achieved using glycated compounds that bind glycoproteins and reduce glycoprotein activities.