A new scientific peer-reviewed study by a California cannabis research and development company explains the chemical origins of the skunky gasoline scents and flavors present in some cannabis cultivars.
Tustin-based Abstrax today announced the study results, allowing researchers to further examine the properties of the specific compounds.
Solving a Scientific Puzzle
According to Abstrax, the source of the compounds that generate the scent has puzzled the cannabis science community.
Abstrax says, while cannabis aromas are traditionally associated with terpenes, no combination of them can generate cannabis’ distinct skunk-like scent.
A team led by Abstrax’s T.J. Martin discovered a new family of compounds responsible for the scent.
The family of compounds includes sulfides, thiols, and disulfides.
Abstrax found that each compound contributed to distinct cannabis’ skunk-like scent, combined with other aroma compounds like terpenes.
The team discovered the key volatile sulfur compounds (VSC) by using two-dimensional gas chromatography (2DGC) together with mass spectrometry, flame ionization detection, and sulfur chemiluminescence.
VSCs are sulfur-containing organic compounds Abstrax says are linked to the pungent aroma of cannabis.
“The combination of multiple detectors, in tandem with 2DGC to analyze cannabis, gave us the tools needed to parse through data and identify trends between certain compounds and the aroma of various cannabis cultivars,” says study lead author Dr. Iain Oswald. “Our data conclusively establishes a link between this new family of VSCs in cannabis and its pungent aroma.”
The Process
Abstrax says that, while gas chromatography is typically used to analyze the volatile species of flower, food, and beverage samples, cannabis presents a uniquely complex case because of its wide variety of compounds.
According to Abstrax, 2DGC solved the issue because it allowed for greater separation of compounds in the data, allowing easier identification of chemical species.
Abstrax also says that the team used sulfur chemiluminescence to identify compounds in the data.
Sulfur chemiluminescence is a method of specifically detecting compounds with sulfur atoms within their structure.
Abstrax says the process is helpful in situations where there are exceedingly low concentrations of compounds, including the ones in the study.
“Much like Cannaflavins are prenylated flavonoids found specifically in cannabis, some of these newly discovered ‘cannasulfur compounds’ also appear to be highly specific prenylated VSCs to cannabis,” says Dr. Oswald. “It is interesting to see a common chemical theme within entirely different classes of compounds produced by this plant.”
Abstrax says the study results give a starting point for further research conducted in a multidisciplinary fashion.
Through the realization that some cultivars produce the compounds while others do not, Abstrax says it has an opportunity to determine if genetic differences may be the reason.
Eye-Opening Results
Study co-author Mario Guzman, the original breeder of the Bacio Gelato cultivar, says the study opened his eyes.
“It confirmed everything I had thought about some cultivars I have bred—that they are some of the most pungent and medicinal on the market,” says Guzman. “These compounds are the reason Gelato and subsequent crosses are some of the most highly sought after out there.”
Study co-author and OG Kush originator Josh Del Rosso says that the most exciting result of the study was the correlation between the chemical structure of VSCs found in garlic and cannabis.
According to study results, the prenyl functional group found in each VSC measured is, with a few modifications, chemically similar to the allyl group present in garlic.
Abstrax says the VSCs in garlic offer health benefits and suggest that the VSCs in cannabis may provide similar benefits.
“I have suspected for years now that we were missing something in our understanding of this plant,” says Del Rosso. “Although terpenes have been hailed as the major source of the pungent scent of cannabis, we now know that it is this new class of VSCs. I hope that our results can act as a springboard to help other researchers determine if these compounds endow cannabis with even more medicinal properties that we ever imagined.”
Compound Volatility
Abstrax CSO Kevin Koby says that the compounds can translate from cannabis flowers to concentrates if properly extracted.
“Their high volatility makes them prone to volatilization, so we weren’t sure how they would translate into cannabis extracts,” says Koby. “We were pleasantly surprised to see high levels in the sample we measured, especially if these compounds possess beneficial medicinal properties.”
Abstrax says the study measured VSCs as a function of plant growth.
Researchers discovered that the compounds increased substantially toward the end of a plant’s growth and reached a maximum right after the curing process.
According to Abstrax, VSC concentrations dropped substantially after a week of storage.
Koby says the results prove that cannabis producers are racing against time to get quality products into customers’ hands.
“Hopefully our results will establish a new standard for cultivators and distributors to help preserve and protect these key compounds—regardless of the rigors of processing, packaging, and time on the shelf,” says Koby. “Most importantly, it will help brands maximize their products and literally push cannabis quality to the next level.”
