Decarboxylation— A Multi-Purpose Process Step

Decarboxylation is the process through which acidic cannabinoids, like THCA, convert to their neutral forms, like THC. Often, the purpose of this step is to "activate" the THC in order for consumers to feel the effects of THC in an edible form. However, in this article other reasons to decarboxylate cannabis are explored.

What is Decarboxylation?

Decarboxylation is the process of heating cannabis to activate its compounds by removing a carboxyl group from their molecular structure. This seemingly subtle alteration is pivotal, unlocking the intoxicating effects of tetrahydrocannabinol (THC), making them readily available for recreational consumption. While there are benefits and uses to cannabinoids in their acidic forms, decarboxylation is the subject of this article.

At the heart of decarboxylation lies a fundamental understanding of cannabis chemistry. In its raw form, cannabis contains predominantly cannabinoid acids such as tetrahydrocannabinolic acid (THCA) and cannabidiolic acid (CBDA). These compounds are not psychotropic. However, after THCA undergoes decarboxylation and becomes THC, it yields the familiar associated effects of THC. In addition, the acidic and decarboxylated compounds provide different therapeutic benefits which makes each cannabinoid of value.

Why Decarboxylate Cannabis?

Product Consistency:

In the realm of edible cannabis products, decarboxylation is vital for achieving consistent potency and predictable effects. Whether infusing oils, butter, or other ingredients, decarboxylating cannabis prior to incorporation ensures that the final product delivers the intended therapeutic or recreational effects reliably. Standardized decarboxylation protocols empower manufacturers to control the cannabinoid profile of their products, meeting the diverse needs and preferences of consumers.

However, achieving optimal decarboxylation requires careful attention to various factors, including temperature, time, and moisture content. Too high a temperature or prolonged exposure can degrade cannabinoids and can affect the overall quality of the final product, like flavor. Conversely, inadequate decarboxylation may result in suboptimal potency and inconsistent effects.

Fortunately, advancements in technology and scientific understanding have facilitated precise control over the decarboxylation process. From laboratory-scale equipment to commercial-grade machinery, a range of tools is available to tailor decarboxylation parameters to specific needs, ensuring maximum efficiency and quality.

Increase Extraction Efficiency:

A less recognized benefit of pre-treating cannabis biomass by decarboxylation is a reduction in water content. Water is an extremely polar molecule and is particularly disruptive to supercritical CO₂ and ethanol extraction. Extraction efficiency and product quality increase with dry material as the solvents can focus on extracting the desired compounds, like cannabinoids, as opposed to co-extracting water.

Polarity of the solvent and the solute is another factor that affects efficiency of extraction as well as the solubility of the solute in the solvent. The acidic forms of cannabinoids are more polar than the neutral or “decarboxylated” forms. For example, both THCA and THC are relatively non-polar molecules. However, THCA is more polar than THC. In the extraction world, the phrase “like dissolves like” can help with understanding how these molecules will behave in various conditions and with various solvents. Table 1 (1) shows the polarity of the most common extraction solvents.

Depending on the solvent, decarboxylating cannabinoids prior to extraction can increase extraction efficiency. Efficiency is paramount in the realm of cannabis extraction, where maximizing yield while preserving quality is a constant endeavor. Decarboxylation can play a role in this regard by priming the cannabinoids for extraction. This activation step ensures that the desired cannabinoids are more readily available for extraction, leading to higher cannabinoid yields.

Decarboxylation of cannabinoids has mixed results with respect to the effect on binding affinity of the cannabinoids(2,3) to cannabinoid receptors. Binding affinity can be defined as the extent or fraction to which a drug binds to receptors at any given drug concentration or the firmness with which the drug binds to the receptor (4). In the case of cannabis, decarboxylation may enhance the efficacy of a cannabis product. Cannabinoids like THC or cannabigerol (CBG) have a higher binding affinity to cannabinoid receptors than THCA or cannabigerolic acid (CBGA). However, CBDA has a higher affinity for cannabinoid receptors than cannabidiol (CBD) (2).

Conclusion

In conclusion, decarboxylation stands as a multi-purpose tool of cannabis extraction and product manufacturing. It offers a multitude of benefits for both producers and consumers alike. By converting cannabinoids from their acidic to their neutral forms, extraction efficiency increases, binding affinity to cannabinoid receptors may increase, and product consistency may increase. Through the activation of cannabinoid acids, decarboxylation ensures the delivery of potent and consistent formulations tailored to meet the diverse needs of consumers. As research in cannabis science continues to advance, a deeper understanding of decarboxylation mechanisms will pave the way for the development of standardized extraction protocols and optimized product formulations.

References

1. Lazarjani MP., Young O., Kebede L., Seyfoddin A., Processing and extraction methods of medicinal cannabis: a narrative review. J Cannabis Res. 2021; 3(1):32. doi: 10.1186/s42238-021-00087-9
2. Wakshlag JJ., Schwark WS., Deabold KA., Talsma BN., Cital S., Lyubimov A., Iqbal A., Zakharov A., Pharmacokinetics of Cannabidiol, Cannabidiolic Acid, ∆9-Tetrahydrocannabinol, Tetrahydrocannabinolic Acid and Related Metabolites in Canine Serum After Dosing With Three Oral Forms of Hemp Extract. Front Vet Sci. 2020; 7:505. doi: 10.3389/fvets.2020.00505
3. McPartland JM., MacDonald C., Young M., Grant PS., Furkert DP., Glass M., Affinity and Efficacy Studies of Tetrahydrocannabinolic Acid A at Cannabinoid Receptor Types One and Two. Cannabis Cannabinoid Res. 2017; 2(1):87-95. doi: 10.1089/can.2016.0032
4. Salahudeen MS., Nishtala PS,. An overview of pharmacodynamic modelling, ligand-binding approach and its application in clinical practice. Saudi Pharm J. 2017; 25(2):165-175. doi: 10.1016/j.jsps.2016.07.002

About the Columnist

Lo Friesen is the founder, CEO, and Chief Extractor of Heylo. With a background in chemistry and clinical research, Lo was inspired to explore cannabis as a medicine and to enter the emerging industry. She joined Eden Labs, a leading CO₂ extraction equipment manufacturer to support and expand a Research and Development department. There she managed the development of their latest and greatest CO₂ extraction system. In 2017, after working with Eden Labs and another cannabis processor, Lo launched Heylo with a mission to help people get more out of life with cannabis.

How To Cite this Article

Friesen, L., Decarboxylation—A Multi-Purpose Process Step, Cannabis Science and Technology, 2024, 7(2), 12-13.