Golden liquid churns in six glass vessels, each hooked up to a computer via a bundle of tubes and wires. Air pumps buzz, and the room smells of bananas and old beer. But this facility – I was allowed to visit on the condition I not use its name or location – is no brewery. Its operators are making cannabis products using microbes instead of plants.
Humans have been cultivating cannabis plants for thousands of years, first for their fibres and later for their cannabinoid molecules, some of which have psychoactive and therapeutic properties. But we can now make those molecules without plants.
For at least five years, synthetic biologists have been producing cannabinoids using bioengineered yeast, more recently including tetrahydrocannabinol (THC), the cannabinoid behind cannabis’ psychoactive effects.
Moreover, the yeast can make large quantities of cannabinoids that are present in low concentrations in the plant, some of which may have potential medical uses. And they have a smaller environmental footprint than farming. “I don’t see how plants ever compete when we get to scale,” says Ben Chiarelli at Cellibre in California, one of a number of start-ups aiming to capitalise on microbial cannabinoids.
But for all this ambition, the industry has struggled: several companies recently went bankrupt and others are abandoning their yeast vats for other projects. Challenges in finding funding and worry about protecting proprietary processes have made some in this space wary of attention at the moment too – hence the terms of my recent visit.
Despite this stuttering …