Since Nigella sativa, Ivermectin and Pfizermectin are all protease inhibitors, I have taken it upon myself to start up this big fat list of every protease inhibitor I can find, and look for any studies on any of them for use to treat C19 or respiratory viruses, in general.
I was pleased to find out that Ginkgo leaf, which I drink in tea regularly, not only has quercetin, which I knew about, but another, less known protease inhibitor called rutin, as well.
Let's begin:
The study:
https://www.ncbi.nlm.nih.gov/labs/pmc/articles/PMC7985176/
The plants:
Torreya nucifera - A Japan / Korean native plant with a long history of use in food and other purposes like making vegetable oil.
Isatis tinctoria - Also used for centuries as an herbal medicine. Also used in blue dyes, oddly enough, but is still usable as traditional medicine.
Rheum palmatum AKA Chinese rhubarb - edible, with a long history use in traditional medicine.
Psoralea corylifolia - Another plant with a long history of use in traditional medicine.
The study:
https://pubmed.ncbi.nlm.nih.gov/22465253/ (Not for coronavirus, but still demonstrated efficacy in inhibiting viral activity.)
Fisetin - Compound found in many fruits and vegetables, including strawberries.
Rutin - Compound found in many fruits, vegetables, and other common edible herbs. This includes buckwheat, eucalyptus, elder flowers (also high in zinc!), and ginkgo leaf (also contains quercetin!).
And guess what? Rutin and fisetin supplements are available over the counter! Talk to your doctor to make sure it won't conflict with any other medications you take, or pre-existing conditions, and think about throwing that in with your daily Z-Stack!
SHARE THIS INFO AND SAVE LIVES, FRENS!
Years ago I saw a study (one of the big nurses studies of the 80/s90s I think) that found the participants who ate the most strawberries lived longer than the others. Strawberries are the best-known source of fisetin.
Newer research bears that out and explains why. See also here for more; many of these have a good number of references for those interested.
Correction - strawberries are the best known source of fisetin that is not deathly poisonous to humans due to other, non-fisetin compounds also present in the plant. ;)
Ah. Did not know that. Nice that such a tasty treat is the non-poisonous exception to the rule.