Extracting medically useful cannabinoids like THC and CBD from the plant can be costly and inefficient.
Now researchers have figured out a way to reverse engineer brewer’s yeast to take sugar and create cannabinoids instead of alcohol.
The Trouble with Cannabinoid Production
Despite a rocky history, there has been a steadily growing resurgence in interest towards the medicinal value of the cannabis plant.
Several countries have approved various cannabinoids as prescription drugs. One of the more notable examples is the approval of cannabidiol (CBD) by the U.S. FDA to treat certain rare and severe forms of epilepsy.
As a result, the demand for these compounds is on the rise. But the research and production of cannabinoids are still hampered by a few different factors.
Firstly, cannabis is still classified as illegal in many countries around the world. Additionally, extraction of cannabinoids from the cannabis plants gives relatively low yields. Lastly, the structural complexity of cannabinoid compounds makes mass production tricky.
But what if there was a better way?
A New Approach
Researchers at the University of California, Berkeley managed to bypass the major downsides of cannabinoid production by getting rid of the plants altogether. They published their results in the journal Nature.
The researchers genetically modified Saccharomyces cerevisiae—commonly known as brewer’s yeast—that’s used to make wine, bread, and beer. Using biological engineering techniques, they inserted genes from the cannabis plant into the yeast genome.
Normally, yeast turns sugar into alcohol, but the researchers co-opted this process to turn sugar into cannabinoids. To do this, they inserted over a dozen cannabis genes required for the production of cannabinoid compounds into the yeast genome.
Cannabinoid compounds are very complex. The researchers had to make sure that each chemical step was accounted for in the complicated process of turning sugar into cannabinoids.
They even inserted genes from several different types of bacteria that could create the proper cannabinoid building blocks from sugar.
With the cannabis and bacterial genes inserted, the modified yeast successfully produced the major cannabinoids CBD and tetrahydrocannabinol (THC) from sugar.
The researchers also added cannabis genes to produce two other cannabinoids, cannabidivarin (CBDV) and tetrahydrocannabivarin (THCV). While CBDV and THCV are also naturally-occurring cannabinoids, they are not well studied or understood.
This is certainly not the first time that scientists have used yeast as tiny molecular factories. The pharmaceutical industry already uses yeast to produce vaccines, insulin, and blood clotting factors.
However, this is the first time that researchers have used yeast to produced cannabis-derived compounds. Here are some of the implications of this significant achievement.
Jay Keasling, the Berkeley professor of chemical and biomolecular engineering who oversaw this study, has already started a company, Demetrix, Inc., and is working on commercially producing cannabinoids in yeast. If Demetrix succeeds, consumers will benefit from low-cost, pure CBD and THC.
Cannabinoid production in yeast could allow manufacturers to achieve a higher level of quality control. This means customers will be able to more accurately and confidently dose themselves.
This is particularly important for CBD production. Most CBD products made from plant extracts still contain some levels THC. But many consumers and patients wish to avoid the psychoactive effects of THC.
In news coverage from UC Berkeley, the authors of the study also claim that using yeast to make cannabinoids is more environmentally friendly than growing cannabis plants.
Cannabis cultivation and extraction requires synthetic and often toxic pesticides, fertilizers, and chemicals. If not used responsibly, these chemicals can end up contaminating public waterways. Indoor growing operations also use a substantial amount of electricity to run light temperature control units.
Even if these environmental claims do not hold up, bypassing the need to grow cannabis plants makes the process less legally complicated for producing unscheduled cannabinoids like CBD.
New Research Avenues
Lastly, this could help researchers get a better understanding of the lesser studied cannabinoids.
Aside from the abundant THC and CBD, many cannabinoid compounds are present in very low levels in the cannabis plant. This means producing these chemicals in high enough amounts for scientific studies is very difficult.
With yeast cannabinoid production, researchers could now have an ample source for the lesser abundant, naturally-occuring cannabinoids.
There’s also the possibility of creating novel cannabinoids that don’t occur naturally in the plant but could have useful medicinal properties.
What about the entourage effect?
Many believe that whole cannabis plant extracts are more effective than isolated cannabinoid compounds due to a phenomenon known as the entourage effect.
It states that the effects of cannabis depend on the synergy between all of the compounds contained in the plant. This includes THC, CBD, the more than 100 other cannabinoids, and the dozens of terpene compounds.
Others are skeptical, but more research will be needed to tell us whether isolated cannabinoids can be as effective as whole plant extracts.
This new breakthrough in cannabinoid production has major implications for the commercial manufacturing of cannabinoid compounds.
With the creation of their own company, we’ll have to wait and see if the researchers can translate their successful experiments into a commercially viable solution for the cannabis industry.