Coronavirus Disease 2019 (COVID-19) is pandemic and is caused by severe acute respiratory
syndrome coronavirus 2 (SARS- CoV-2). The rising number of cases of this highly transmissible
infection has prompted an urgent need to identify and develop effective antiviral interventions
that may reduce the health risks associated with this disease. The life cycle of SARS-CoV-2 includes a viral entry, viral replication, viral assembly and release. The symptoms associated with viral infection often lead to fatal outcomes with pneumonia, myocarditis, acute respiratory distress syndrome, hypercoagulability, and/or multi-organ failure.
Recent studies have reported that plant-derived substances, such as quercetin, emodin, epigallocatechin gallate, and berberine may, albeit modestly, inhibit different stages of SARS-CoV-2 life cycle in the host. For example, these substances in some in vitro and in vivo model systems appear to disrupt viral infection and replication by blocking viral-surface spike protein binding to entry receptor angiotensin-converting enzyme (ACE2), inhibiting viral membrane fusion with host cells, inhibiting main proteinase (Mpro) and RNA-dependent RNA polymerase involved in viral replication, and/or pathological host- responses in vitro.
Various functional foods/nutraceuticals, even though not defined by the US government, and
dietary supplements may modulate host defense function(s) and overall health status, and thus
possibly lower the risk of COVID-19 infection. However, these data are inconsistent and need
further clinical evaluation.
Some studies suggest that a balanced diet rich in various nutrients especially specific
micronutrients may have a significant role in reducing risks associated with COVID-19 and during the recovery phase. Obesity, type 2 diabetes, and cardiovascular disease are among the noncommunicable diseases associated with increased inflammation. A decrease in obesity, which is multifactorial in etiology, may reduce the risk of severe COVID-19 inflammatory responses. This response may be due to fewer ACE2 receptors (depending on tissue type), changes in their binding affinity or alterations in associated proteases and an array of genetic factors.
An increased awareness in food science and dietary components may represent important and
critical roles in reducing the risk of SARS-CoV-2 viral infection, growth, and disease progression as well as provide a perspective on the potential use of these plant-derived substances in the
development of novel interventions against SARS-CoV-2.