Friday Hope: Confirmation of the Effects of Tea on SARS-CoV-2 and its Spike Protein

Evidence supporting previous Friday Hope hypotheses.

Analysis of inactivation effects of tea and green tea catechins on SARS-CoV-2 Omicron variants. Viruses were treated with the indicated tea (a) or each catechin at the same concentration in bottled green tea beverage (Supplementary Table 1) (b) for 10 s. After dilution, the virus was infected to VeroE6/TMPRSS2 cells to determine TCID50 values as described in the Materials and Methods. Virus titer of each sample (means ± S.D.) is shown (n = 4). ****p < 0.0001, ***p < 0.001, **p < 0.01, and *p < 0.05 vs. Control (distilled water) (Tukey’s multiple comparisons test).

Readers of this Substack may recall that I posted back in January an article hypothesizing that tea and tea extracts may inhibit the formation of fibrils (Amyloidosis) and SARS-CoV-2 replication. A paper was published Tuesday which confirms the inhibitory findings of that post.

The team reporting these recent findings had previously determined that EGCG "powerfully and rapidly" inactivated the virus. In addition, black tea compounds such as deriviatives of tea cathecins had similar effects. Perhaps most importantly, these compounds bind to the RBD of the Spike Protein, rendering it unable to bind to ACE2.

We reported that exposure of the virus to green tea, roasted green tea, oolong tea and black tea in vitro resulted in significant reduction of the virus infectivity16,17,18. We also found that the tea catechin compound (−)- epigallocatechin gallate (EGCG) powerfully and rapidly inactivated the virus16,17,18, which was also reported by other groups19,20,21. Similar effects were also seen in black tea ingredients, galloylated theaflavins (theaflavin-3-O-gallate (TF3G), theaflavin-3’-O-gallate (TF3’G), and theaflavin-3,3’-O-digallate (TFDG)), and theasinensin A (TSA) that are derivatives of tea catechins17,22. We also reported that the EGCG, TFDG and TSA interfered with the interaction between viral spike protein and ACE2 by binding to the spike protein receptor binding domain (RBD).

The effects observed initially also continue with Omicron subvariants.

Neutralizing assay was performed to test whether EGCG, GCG and TFDG prevented interaction between RBD of the BA.1 Spike protein and ACE2. As results, the interaction between RBD and ACE2 was strongly suppressed by EGCG, GCG and TFDG that were mixed with RBD followed by an addition of the resultant RBD/compound mixture to ACE2-pre-coated wells (“mix protocol”) (Fig. 4b, c, and green bars in d). In contrast, the protein interaction was not significantly inhibited if ACE2 was pretreated with EGCG before an addition of DW-treated RBD (Fig. 4d, pink bars). These data strongly suggest that EGCG inhibited interaction between RBD and ACE2 by binding to RBD rather than to ACE2.

What I find extremely promising, and most interesting, is that simply consuming a Green Tea Candy inactivated the virus in saliva. Again, why does Granny need to be "protected" by a gene transfection when a rather flavorful candy can ACTUALLY aid in preventing transmission?

The virus was significantly inactivated by the treatment with saliva from healthy volunteers who consumed a candy containing green tea or black tea, provided that the saliva was collected from the volunteers immediately after the cessation of the candy consumption (Fig. 7). Five or 15 min after the cessation of the candy, the inactivation effect was almost lost in the saliva.

The paper concludes with a statement I couldn't agree with more. Tea cathechins may hold great promise in suppressing the transmission of mutant viruses. Somethine we should whole heartedly embrace investigating further.

These results indicate specific amino acid substitutions in Omicron RBDs that crucially influence the binding of EGCG/TFDG to the RBDs and different susceptibility of each Omicron subvariant to EGCG/TFDG. The study may suggest molecular basis for potential usefulness of tea catechins and their derivatives in suppression of transmission of mutant viruses that could emerge in the future and cause next pandemic.

Effects of tea, catechins and catechin derivatives on Omicron subvariants of SARS-CoV-2
https://www.nature.com/articles/s41598-023-43563-3

As always, blessing to all and a happy Holiday Weekend to those here in the States. Thank you for your continued support and encouragement. I am humbled and immensely thankful.