We as species would be unhappy without yeast. Baker's yeast has given us sourdough bread for thousands of years. And I do not even want to imagine a world without beer and wine, which relies on yeast to turn sugar into alcohol.
Now yeast researchers are turning to do something less improbable: the production of the cannabis compounds CBD and THC. By loading brewer's yeast with genes from the cannabis factory, they have turned the miracle microbes into cannabinoid factories. It is a wise scheme in a larger movement to methodically dissect and recreate the many compounds of marijuana to better understand the true potential of the plant.
The process runs like this. Depending on the type of enzyme, two different yeasts produce either THC or CBD. Importantly, both carry the cannabis genes that produce CBGA. "CBGA is one such central cannabinoid that is the mother of all other cannabinoids," says Jay Keasling, chemical engineer at UC Berkeley, co-author of a new article in Nature detailing the technique.
For the production of THC This yeast produces CBGA, which then becomes THCA thanks to the yeast's special enzyme. For CBD yeast, its own enzyme turns CBGA mother cannabinoid into CBDA. (Alphabet soup, I know, but stay with me.) Now you have THCA and CBDA, which are transformed by the application of heat to THC and CBD.
The tail is no different from the cannabis plant itself. If you were to eat raw cannabis, it is unlikely that you will get high because it is mostly THCA. Only after you apply heat does THCA convert to THC. (Although THCA will slowly convert THCA into THC as a cure for cannabis blooms over time.) Essibles works because manufacturers first convert THCA to THC as decarboxylation.
The reason that researchers and cannabis companies are interested in alternative ways to make cannabinoids Working with the original device is confusing and complicated. First of all, growing the material costs a lot of time, water and energy (if you are cultivating indoors). Extracting certain cannabinoids from the flower is also awkward. For example, if you are first on CBD, your extract may be contaminated with THC. This is especially important if you want to isolate CBD for use as a drug ̵
If you have a yeast container that promises pure, non-psychoactive CBD promise to massively simplify production. "It's a pretty valuable thing to do that in a way that's not contaminated with THC," says Keasling. Especially as the FDA may want to talk to you if you accidentally dose patients with a psychoactive substance.
Cannabinoid-producing yeast may also make it easier to study cannabis in the first place. We are talking about an extremely complicated plant with more than 100 different known cannabinoids. Some of these compounds are more common than others – modern cannabis strains are filled with THC, as cultivators have bred varieties that have become increasingly rushing over the years. However, a cannabinoid such as tetrahydrocannabivarin or THCV is found in much smaller quantities. "Now it's up to us to make these things in a straightforward way, and in a relatively simple way, maybe we can start testing their functions," says Keasling.
Engineered yeasts were used to address the scarcity problem in other ways before. In the 1960s, researchers discovered that taxanes from Pacific yew bark can fight cancer. All well and good, with the exception of the Pacific yew, which was feared by conservationists, would die out in the hands of an eager medical establishment. But as with this cannabinoid-producing yeast, the researchers developed microbes to make the drug deforestation-free.
In cannabinoids the main advantage is the size. The idea is that it's far easier to crank out CBD volumes in vats than plant greenhouse to greenhouse of cannabis plants. (That does not mean that some people do not always appreciate their cannabis, which is grown in an old-fashioned way.) But to make it as efficient as possible, one would have to work with as high a cannabinoid concentration as possible. That means you want to optimize your yeast to produce a whole lot of product.
"Can you continue to increase concentration or become toxic to the organisms you actually use? That's why you have a limit? "Asks Jeff Raber, CEO of Werc Shops, a lab that dissects the ingredients of cannabis.
Regardless of production hurdles, the beauty of this type of biotechnology is that it provides researchers with a powerful platform not only to investigate what each cannabinoid might be useful for, whether it be to treat anxiety, inflammation or epilepsy, but also how to treat it many cannabinoids in the plant could interact with each other. This is called the entourage effect: for example, CBD appears to attenuate the psychoactive effects of THC.
The selective rollout of these cannabinoids in the laboratory will make it easier for researchers to isolate and play with each other without having to go through hundreds of other compounds that you would find in bloom. "Ultimately, a molecule is a molecule," says Raber. In fact, yeast cannabinoids are the same cannabinoids as the plant. "There is flexibility in the formulation, it may have a wider utility and can scale faster than plants. Regulators may feel much better at such approaches than those that are fields and fields and fields of plant material. "
However, this does not stop with cannabinoids. What Raber and other researchers are pursuing is essentially a reconstruction of the chemical profile of cannabis. For example, terpenes give the smell its characteristic odor, but you will find them everywhere in the plant kingdom: limonene is not particularly abundant in cannabis, but it is a rich product of the citrus industry. The idea is, instead of mourning, to extract small amounts of limonene from a cannabis plant, you can get it from lemons instead.
The ultimate goal is to tailor cannabis products, such as tinctures, to a specific size. This would allow for a tailored ratio of CBD to THC and possibly other cannabinoids and terpenes, which may even play a role in the entourage effect. For example, the terpene linalool may have anxiolytic effects.
Let us celebrate yeast, this miracle germ and the creator of all good things in the vicinity: bread, brandy and biotechnologically produced cannabinoids.
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