Last week brought the sad news that iconic cannabis researcher Professor Raphael Mechoulam had died aged 92. Professor Mechoulam is well-known for making significant contributions to the study of medical cannabis over a career spanning more than 60 years – contributions that earned him the nickname “the Father of Cannabis Research”. His list of achievements includes contributing to our understanding of three of the most well-known cannabinoids: Delta-9 tetrahydrocannabinol (THC), cannabidiol (CBD) and cannabigerol (CBG).  

His research in this area led not only to a significant leap in our understanding of the chemistry of the cannabis plant but also to the discovery of the human endocannabinoid system (ECS). Since the discovery and isolation of THC in 1963, Professor Mechoulam continued to highlight the therapeutic importance of cannabis throughout the rest of his career and life. In the 1980s he famously claimed that, if cannabis were to be legalised, it could replace up to 20% of pharmaceutical drugs – a belief that was decades ahead of its time.  

In honour of this incredible scientist and researcher, we’re taking a look over the life and legacy of Professor Raphael Mechoulam. 

The Life of Professor Raphael Mechoulam 

Raphael Mechoulam was born in Sofia, Bulgaria in 1930, later emigrating to Israel with his parents in 1949. On his arrival in Israel, he had already earned a degree in chemical engineering which paved the way for the rest of his career in chemistry. By the early 1960s, Professor Mechoulam had completed a master’s degree in biochemistry at the Hebrew University of Jerusalem, a thesis on steroid chemistry earning him a doctorate at the Weizmann Institute of Science in Rehovot, and two years of postdoctoral studies at the Rockefeller Institute in Manhattan, New York. 

In 1965, Mechoulam returned to the Hebrew University in Jerusalem where in 1972 he was appointed Associated Professor and in 1975 as Professor of Medicinal Chemistry. It is here that Professor Mechoulam conducted much of his important cannabis research right up until his death. But his notable work into the structure and components of cannabis began even before this.  

Mechoulam’s Contributions to Cannabis Research 

Mechoulam’s interest in cannabis research stemmed from an observation that other pharmaceutical drugs had been isolated from natural plants, as he explained in an interview with CNN in 2014: “Morphine had been isolated from opium in the nineteenth century, early nineteenth century, cocaine had been isolated from coca leaves [in the] mid-nineteenth century. And here we were, mid-twentieth century, and yet the chemistry of cannabis was not known. So, it looked like [an] interesting project.” 

Medical cannabis research chemistry

And an interesting project it was indeed. Mechoulam’s extensive work in this area, in collaboration with many talented and dedicated scientists, has yielded some incredible discoveries about the potential of cannabis. 

The isolation and study of common cannabinoids 

In 1963, Raphael Mechoulam, alongside some of his Hebrew University collaborators, reported the isolation of THC across several papers – the first of which dates from 1963. Since then, THC has become one of the most researched cannabis compounds, thanks to its significant psychoactive and therapeutic properties. Studies into THC’s isolation, structure elucidation, stereochemistry, and activity conducted at this time remain some of the most significant in cannabis research history and continue to inform further study to this day. 

While CBD was the first cannabinoid to be isolated in 1940 – predating Mechoulam’s work – this cannabinoid was largely ignored for decades in favour of the psychoactive THC. However, in 1963, Mechoulam and his team were able to finally describe the structure of CBD. These two achievements alone carried significance for many decades to come. But Mechoulam wasn’t done there.  

Endocannabinoids and the Endocannabinoid System 

After almost two decades of continued study into the biochemistry and potential medicinal properties of cannabis compounds, Professor Mechoulam and his team demonstrated for the first time that cannabinoids display stereoselectivity. This finding prompted the search for cannabinoid receptors in mammalian tissues. The discovery of CB1 receptors between 1988 and 1990 and of CB2 receptors in 1993 launched the race to discover the endogenous chemicals that activate these receptors – the endocannabinoids. 

Once again, Professor Mechoulam and his collaborators were at the forefront of this research. Mechoulam’s team gathered evidence of the endogenous production of N-arachidonoyl ethanolamine – which they named “anandamide” after the Sanskrit word meaning “bliss” or “joy” – and 2-arachidonoylglycerol (2-AG) and that both compounds could activate cannabinoid receptors. Together, these discoveries led to the first mapping of the Endocannabinoid System.  

The discovery of the Endocannabinoid System influenced medical cannabis research immeasurably. From these findings came our understanding of the ECS’s role in important physiological and cognitive functions, in addition to protective roles in several serious conditions. Hence, researchers were able to theorise that “some disorders could be treated with drugs that enhance the levels of protectively released endocannabinoids within and/or without the central nervous system.” 

Other Notable Achievements 

Despite his already incredible list of contributions to medical cannabis research, Mechoulam continued to work and advocate for increased access to medical cannabis right up to his death. Until his final days, Professor Mechoulam was the President of the Hebrew University’s Multidisciplinary Centre for Cannabinoid Research – the largest cannabis research centre in the world. It is largely thanks to Mechoulam’s work that this centre exists and continues to conduct breakthrough cannabinoid research. 

Cannabis Plant

As though this wasn’t enough, Professor Mechoulam was also the recipient of an Honorary Doctorate from Ohio State University, an Honorary Doctorate from Complutense University, a NIDA Discovery Award, an EMET Prize in Exact Sciences for his contributions to Chemistry and a Lifetime Achievement Award from CannMed. But many believe that he still deserved more recognition.  

In more recent years, Prof. Mechoulam embraced modern communications in the form of two podcasts, appearing on Episode #150 of The Cannabis Conversation and Episode #35: ‘The Godfather of Cannabis’ of the Professionally Cannabis Podcast. Such appearances were just the tip of the iceberg when it came to Professor Mechoulam’s unwavering dedication to cannabis education.

Tributes to a Cannabis Icon 

Many left touching tributes to Mechoulam – the Father of Cannabis Research in the days following the announcement of his passing, including those from the science and cannabis communities, alike. Professor Raphael Mechoulam was, and remains, one of the most influential figures in the cannabis world – a man who dedicated his time not only to his own research but also to encouraging the wider scientific community to invest more time and money in understanding this incredible plant.