The phytochemicals found in flower petals of Himalayan Buransh plant (Rhododendron) can potentially be used to treat Covid infections, the researchers from the Indian Institute of Technology Mandi and the International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi said on Monday.

The findings of the research team which was led by Dr Shyam Kumar Masakapalli of IIT Mandi and Dr Ranjan Nanda and Dr Sujatha Sunil, ICGEB, New Delhi, have been recently published in the journal ‘Biomolecular Structure and Dynamics.

IIT Mandi associate professor Dr Shyam Kumar Masakapalli said two years into the Covid-19 pandemic, the researchers are trying to understand the nature of the virus and discovering new ways to prevent the infection.

While vaccination is one route to providing the body with the fighting power against the virus, there is a worldwide search for non-vaccine medicines that can prevent viral invasion of the human body. These medicines use chemicals that either bind to the receptors in our body cells and prevent the virus from entering them or act on the virus itself and prevent its replication inside our bodies.

“Among the different types of therapeutic agents being studied, phytochemicals – chemicals derived from plants – are considered particularly promising because of their synergistic activity and natural source with fewer toxicity issues. We are hunting for promising molecules from the Himalayan flora using multi-disciplinary approaches

The petals of the Himalayan Buransh plant, scientifically called Rhododendron arboreum, are consumed in various forms by the local population for their varied health benefits. The scientists from IIT Mandi and ICGEB set out to scientifically test the extracts containing various phytochemicals in it, with a particular focus on antiviral activity. The researchers extracted the phytochemicals from the Buransh petals and performed biochemical assays and computational simulation studies to understand its antiviral properties,” he added.

Dr Ranjan Nanda, Translational Health Group, ICGEB, New Delhi said ‘we have profiled and investigated the phytochemicals of Rhododendron arboreum petals sourced from Himalayan flora and have found it to be a promising candidate against the Covid virus.’

He stated that hot water extracts from these petals were found to be rich in quinic acid and its derivatives. Molecular dynamics studies showed that these phytochemicals have two kinds of effects against the virus.

They are bound to the main protease, an enzyme that plays an important role in viral replication, and to the Human Angiotensin-Converting Enzyme-2 (ACE2) that mediates viral entry into the host cells.

The research also showed through experimental assays that non-toxic doses of the petal extracts can inhibit Covid infection in Vero E6 cells (cells derived from the kidney of an African green monkey that is commonly used to study infectivity of virus and bacteria), without any adverse effects on the cells themselves.

Dr. Sujatha Sunil, Vector-Borne Disease Group, ICGEB said a combination of phytochemical profiling, computer simulations, and in vitro antiviral assays showed that the extracts from the Buransh petals inhibited the replication of the COVID-19 virus in a dose-dependent manner.

The findings support the urgent need for further scientific studies aimed at finding specific bioactive drug candidates from Rhododendron arboreum, in vivo and clinical trials against Covid. The research team also plans to carry out additional studies to understand the precise mechanism of inhibition of Coronavirus replication by specific phytochemicals from Buransh petals.