Epigallocatechin-3-gallate (EGCG) is one of the catechins that are found in green tea. It had been ascribed activity as a histone acetyltransferase (HAT) inhibitor. However, a 2017 article by Dahlin et al.
suggests that the thiol-reactivity of EGCG brings in to question its activity as a HAT inhibitor [4
]. Amongst the plethora of health benefits attributed to the catechins, EGCG has demonstrated broad-spectrum antiviral activity [1
]. SARS-CoV-2 and COVID-19:
In relation to SARS-CoV-2, molecular docking analysis suggests that EGCG interacts with the virus' S protein and main protease (Mpro; 3CLpro) [11
]. Evidence also suggests that catechins bind to the S1 ubiquitin-binding site of the virus' second protease PLPro. It is hypothesised that inhibiting PLPro will reduce the enzyme's inhibitory function on the host ubiquitin proteasome and interferon stimulated gene systems, thus targeting some of the inflammatory aspects of SARS-CoV-2 infection.