A biotech company Desert King has developed a procedure that allows the active agents to be released from the bark of the quillaja tree, also known as quillaja saponaria which only grows in Chile. The firm sells the resulting powder to the American vaccine development company Novovax.

In September, the Maryland based company Novovax announced that it has started the phase 3 trial to evaluate the effectiveness and safety of its vaccine in the UK. The General Manager of Desert King, Andres Gonzales, said that if the trails show a green signal, the production of the Coronavirus vaccine could start early next year.

COVID-19 vaccine
Coronavirus vaccine development

He explained that a vaccine includes two major elements, an antigen, which activates a body's own defense, and an adjuvant, which helps release the antigen into the cells and stimulate the immune response in the body.

Quillaja tree has a high content of saponins, which are multipurpose foaming agents and known as natural emulsifiers. But these can be also used to bind substances which don't mix together, and also can be served as adjuvants.

Desert King identified QS7 and QS21, two substances that could work as adjuvant in a potential Coronavirus vaccine after conducting research into 50 odd saponins contained in the quillaja Saponaria. Gonzalez said that the firm is already producing the required amount of quillaja for Novavax.

Quillaja Tree: A Traditional Medicine Facing Climate Change Threat

The Chilean tree can grow to 60 feet in native range and its trunk can reach a diameter of 1.5 meters. The Mapuche—a group of indigenous inhabitants of present-day south-central Chile and southwestern Argentina—have been using the tree for its healing properties and use it as traditional medicine.

The indigenous people use the bark extract as a decongestant—type of medicine that can provide short-term relief for a blocked or stuffy nose—and also treat digestive problems. They also use the flower to treat the symptoms of rheumatism—pain, and inflammation in joints, muscles, and surrounding soft tissue. However, the food industry uses the tree to produce beer.

Quillaja Tree
Quillaja Tree, Chile Wikimedia commons

But due to climate change, the existence of the quillaja tree has under massive threat, said Rene Carmona at the University of Chile in Santiago and added that as Chile is experiencing droughts for 10 years, it has caused immense damage to the trees on slopes in particular.

Gonzalez said these trees should be trimmed rather than cut down to ensure that the quillaja plants have less biomass and need less water which would help it to cope with drought. But as per Carmona, the trees are often cut down for its woods. He hoped that companies like Desert King will help to raise awareness about the importance of protecting the trees.

Carmona also added that an international pharmaceutical company is now using quillaja substances to develop a COVID-19 vaccine which will help to promote the tree's importance to people. "We hope that people will stop using the tree for firewood," he said.