Quercetin

Quercetin

Quercetin is a flavonoid (secondary plant substance) that predominantly occurs in vegetables such as z.Bred onions, red grapes, kale, broccoli, or in wine grapes. A rich source of quercetin is the flowers and flower buds of the Japanese pagoda tree (Sophora japonica L). The purely plant-based flower extract contains at least 95% quercetin.  The human body cannot produce bioflavonoids on its own; therefore, they must be obtained either through supplements or a balanced diet. The problem is that quercetin - like many other flavonoids - has poor natural bioavailability (=indicates the extent, timing, and location of a substance's effect in the body after ingestion).  Effect Regardless of current research findings, the plant substance is attributed with additional positive properties. For instance, quercetin is said to stimulate blood circulation and even have antidepressant effects. It can also regulate blood pressure, strengthen the immune system and positively influence the cholesterol level .   Positive Properties The flavonoid has proven to be a good zinc transporter, as it increases the intracellular zinc level. Zinc, on the other hand, inhibits the enzyme activity necessary for viral replication. Quercetin also appears to block the binding of the spike proteins of the Covid-19 virus to the ACE2 receptors, thereby preventing the entry of proteins into the cell. Other plants and bioflavonoids also exhibit the same ACE2 binding ability.Italian researchers from the Istituto di Nanotecnologia, part of the National Research Council (CNR), have concluded that quercetin inhibits the virus responsible for COVID-19, SARS-CoV-2. The reason for this is the destabilizing effect that the natural substance (bioflavonoid) exerts on the protease 3CLpro, which is responsible for the virus's replication.  "We have observed that quercetin can act as a specific inhibitor for SARS-CoV-2," explains project leader Bruno Rizzuti.  Based on computer simulations, it has been shown that it has a disruptive effect on the protein 3CLpro. This is one of the most important proteins present in SARS-CoV-2 and is crucial for its development; without it, according to the scientists, the enzymatic activity of the virus comes to a halt."One significant advantage is the property that, thanks to its small dimensions and special chemical functional groups, it can be further developed into an even more effective molecule," says Rizzuti.  The details of the research findings were published in the journal "International Journal of Biological Macromolecules." Quercetin is attributed with further positive properties, regardless of current research results. For example, this natural substance is said to stimulate blood circulation and has antidepressant effects. It is also said to strengthen the immune system and positively influence the cholesterol level. References: http://nanotec.cnr.it/en