Dietary factors and SARS-CoV-2 contagion: in silico studies on modulation of viral and host proteins by spice actives

Srividya, Kottapalli; Mir, Snober S; Thiyagarajan, Saravanamuthu; Nazir, Aamir

The SARS-CoV-2 contagion has had a huge impact on world population. It has been observed that despite massive spread of the contagion in India particularly during the second wave, the overall case fatality rates remain low. This prompted us to look into dietary factors that can possibly modulate the viral impact and/or host response. In silico studies were carried out on forty-two commonly used spices and their 637 known active compounds with an aim of identifying such compounds that may have propensity to reduce viral impact or boost host immune response. We chose to study SARS-Cov-2 helicase on account of its functional importance in maintaining viral load within the host, and the human tank binding protein (TBK1) for its important role in host immunity. We carried out in silico virtual screening, docking studies with 637 phytochemical against these two proteins, using in silico methods. Upon assessing the strength of the ligand-target interactions and post simulation binding energy profile, our study identifies procyanidin-B4 from bay leaf, fenugreekine from fenugreek seed and gallotannin from pomegranate seed as active interactors that docked to viral helicase. Similarly, we identified eruboside B from garlic, gallotannin from pomegranate seed, as strong interacting partners to human TBK1. Our studies thus present dietary spice constituents as potential protagonists for further experimentation to understand how spices in the diet might help the hosts in countering the viral assault and mount a robust protective response against COVID and other infections.Communicated by Ramaswamy H. Sarma.