A couple of years ago, a Swiss biochemist came across a substance derived from a strange mossy plant that was being sold online as a “legal high” (obviously, they were only searching this for research purposes). After carrying out some pharmaceutical research on the moss, they discovered that its active ingredient exerts a similar but superior pain-killing and anti-inflammatory effect to tetrahydrocannabinol (THC) in cannabis.

It's early days, but the researchers say it has the potential to become a more effective medical alternative to cannabis.

Back in 1994, Japanese phytochemist Yoshinori Asakawa discovered that the liverwort (Radula perrottetii) – a rare moss native to Japan, New Zealand, and Costa Rica – produced a natural substance known as perrottetinene (PET). He found that PET is related to THC in that individual atoms are linked together in a similar fashion, although they differ in their three-dimensional structure and they have an additional benzyl group.

"It's astonishing that only two species of plants, separated by 300 million years of evolution, produce psychoactive cannabinoids," lead author Jürg Gertsch said in a statement

Researchers from the University of Bern in Switzerland have been exploring the effects of PET and how it compares to its cannabis derived-cousin. As reported in the journal Science Advances, they dosed up a number of mice – one group with an injection of PET and another with THC.

The PET quickly activated the cannabinoid receptors in the mice's brains. Furthermore, it appeared to express an even stronger anti-inflammatory effect than THC. On the other hand, they don’t believe the mice became too stoned as it didn't activate the cannabinoid receptors associated with the euphoric high as prolifically as THC.

"This natural substance has a weaker psychoactive effect and, at the same time, is capable of inhibiting inflammatory processes in the brain," Andrea Chicca, from the Institute of Biochemistry and Molecular Medicine at the University of Bern, added.

The researchers hope that their work paves the way for the therapeutic use of PET, similar to how THC is used to treat various chronic illnesses. However, considering PET has only been used on a small number of animal models, the researchers caution there is a lot of work to be done before it's hailed as the next wonder drug. 

"Both solid fundamental research in the field of biochemical and pharmacological mechanisms as well as controlled clinical studies are required to carry out cannabinoid research," added Gertsch.