An Italian research team has found that pomegranate peel extracts can inhibit the attachment and growth of coronavirus (SARS-CoV-2) thus prevent COVID-19. Ever since this virus has emerged in China, researchers from multiple countries are trying to understand how it works. It has now spread to all parts of the world and noted as one of the deadliest pandemics in whole human history.
In one year, more than a 64.1million people have contracted COVID-19 and nearly 1.48 million of them have lost their lives. While most of these people only experience mild symptoms, some of them suffered from severe complications and even organ failure.
Coronavirus attaches itself to host cells through ACE-2 receptors. Human airways and lungs have higher levels of these receptors, which is why contracting the virus can cause pneumonia, breathing difficulties, and respiratory distress.
Relating ACE-2 receptors with plant-based molecules may sound surprising. But many of these plant-based bioactive compounds can protect from pathogens including viruses.
There are many studies that confirm the antiviral potential of some medicinal plants against coronavirus. Based on these results, it appears that these phenols can be a part of specialized COVID-19 treatment and medicines too.
Polyphenols, bioactive compounds from plants, for example, curcumin, quercetin, kaempferol, naringenin, and catechin restrain viral replication and invasion.
One of these studies proposed to combine two polyphenols that are punicalagin, and theaflavin, into a combination to target ACE-2 host cell receptors. According to them, it could be a helpful way to inhibit the entry of coronavirus inside the host cell.
Furthermore, there is plenty of data that suggests that pomegranate peel extract (PPE) is helpful against the influenza virus, HIV-1 virus, poxvirus, and herpes simplex virus. This antiviral potential of pomegranate peel extract (PPE) may also be effective against COVID-19, according to the researchers.
To investigate their hypothesis, they applied a number of in-vitro techniques to test pomegranate peel extract (PPE) on samples taken from COVID-19 patients.
Pomegranate peel extract (PPE) contains Punicalagin which is found up to 38% followed by pedunculagin anomers (16.7%) and lastly punicalin anomers (13.2%).
The research team used an inhibitor screening-kit to test these polyphenols in three different concentrations. The highest one of them was 1 mg/mL which showed a 74% inhibition rate to limit the interaction between coronavirus and ACE-2 receptor.
Further evaluation of pomegranate peel extract (PEE) showed that punicalagin is responsible for most of its benefits as it is the most abundant polyphenol in pomegranate. Punicalagin was also helpful to inhibit the enzymatic activity involved in this attachment by 50% which is the highest in comparison with other pomegranate polyphenols.
These findings imply that pomegranate peel extract (PPE) can be used to limit the viral entry inside host cells, thus saving millions of people from COVID-19. But it requires further investigation to understand the effect of pomegranate polyphenols and their role to prevent deadly COVID-19.
The complete study findings are published in BioRxiv.