Marijuana may still be on shaky legal ground, but the therapeutic benefits of the psychoactive molecules — cannabinoids — inside the plant are solidly established. Unfortunately, cultivation of that plant is resource-intensive and yields only tiny amounts of some useful medicines. CB Therapeutics, a new biotech company launching today at the Disrupt SF Startup Battlefield, aims to change the game with cannabinoids produced cleanly and cheaply in the lab — out of sugar.

Co-founder and CEO Sher Ali Butt says the idea struck him when he was working at cannabis testing lab Steep Hill. CBD, a compound found in the plant but in much lower concentrations than THC, the primary intoxicant, was producing extremely helpful pain and anxiety alleviation for some people without a high. The medicinal possibilities were obvious, but high-CBD strains of cannabis are not only uncommon, but a pain to cultivate and process for that purpose.

“CBD had all these applications, and I just thought that there’s got to be a better way to do this. The idea just stuck in my brain,” he told me.

After working on the problem on and off for years he decided to pursue it in earnest. Serendipitously, around this time he ran into Jacob Vogan, an old friend from college who was working in the field of bioengineering. It seemed like a natural fit to them to start the company together.

What CB Therapeutics has done is bioengineer microorganisms — specifically yeast — to manufacture cannabinoids out of plain-old sugars. This type of bioreactor isn’t a new idea; yeast and other organisms are used to create and isolate lots of drugs and substances.

“The vitamin C that we take in tablets, for instance — they didn’t squeeze oranges and lemons to get that,” Butt points out. “There isn’t enough agriculture to supply the global demand. It was produced synthetically and put in a box.”

CB Therapeutics is just doing the same thing for cannabinoids, and not just CBD.

“There are 118 cannabinoids, and only five have been studied,” Butt says. “These compounds are like .1, .01, even .001 percent in the cannabis bud. When you want to extract these, a kilogram can be like $100,000 to $350,000. How is someone supposed to do research with that?”

But the yeast don’t care. They take in sugar and output whatever molecule their biosynthesis pathway has been modified to produce — within reason, of course. You couldn’t output large, complex non-organics, but cannabinoids — even the rare ones — are well within their capabilities.

“The only thing we need to add is sugar — that’s the beauty of what we’ve done,” Butt beamed. “The yeast platform is agnostic, it makes everything for the same price.”

This has several benefits. First, it can bring down the price of a known and useful cannabinoid like CBD. Second, it allows the rarer ones to be studied for a reasonable price, and eventually distributed as well. And third, it takes pressure off the agricultural component of the cannabis industry.

That last is not only good from an ecological perspective, since demand is growing and these plants require a lot of water and land, but from the health side as well. Butt points out that a huge majority of cannabis products tested are found to be contaminated to some degree with pesticides and other unwanted compounds.

It’s getting better as the marijuana industry becomes an above-board one, but the problem is far from eliminated, and at any rate pesticides and other potentially harmful chemicals don’t cease to be a nuisance just because something is legal. The risk is there for the foreseeable future that, ironically, the “natural” option of using the plant itself is going to produce more impurities in the product, not less. But the yeast don’t — can’t, really — taint the product. So what comes out of the bioreactor should theoretically be as pure as the driven snow. (CB Therapeutics does test it, of course.)

It’s worth noting that the company’s main intellectual property is is the cannabinoid biosynthesis pathway it has developed. That hadn’t been fully documented or explored, Butt says, until their work.

Butt sees this change as more or less just the latest example of a useful class of molecules going from difficult to relatively easy to acquire.

“When you aren’t able to provide for the demand, that makes prices artificially high. People are going out and spending tens of thousands on CBD, for medical applications,” he said. “Insulin used to be harvested from pig pancreases, then Genentech solved that. Aspirin used to come from tree bark. This is inevitable for many compounds. We need to bring the cannabis price down to where anybody can use it.”

The pricing and volume are still somewhat of a question mark — once testing and the regulatory hurdles are taken care of, like any pharmaceutical it’s going to be a moving target. But scaling production shouldn’t be hard should the demand grow, and the backlog of new cannabinoids to isolate for testing should provide a source of income as well.

Medicine can be a risky sector for startups but CB Therapeutics seems to have it as close to sewn up as one can reasonably expect; in a way it’s almost alchemical, this ability to cheaply produce something so valuable. But really, it’s just science.