Highly Efficient Cannabidiol (CBD) Extraction from Cannabis
Ultrasonic extraction is well known and a long-term established process to extract valuable compounds from botanicals. Therefore, sonification is the ideal technique to produce high-quality CBD oils. By precisely controllable ultrasonic cavitation, plant cells are perforated and the solvent is pushed into the cell, where it absorbs intracellular compounds such as cannabinoids, terpenes, flavonoids etc.
A big advantage of ultrasonication is the temperature range, in which the extraction can be performed. Ultrasonic extraction can be performed from hot/warm ethanol down to cryogenic ethanol (-70°C). This allows for the targeted isolation of the desired compounds. Sonication in cryogenic ethanol yields mainly in cannabinoids and terpenes, whilst a warm/hot ethanol extraction results in the broad variety of phytochemical compounds (e.g. aldehydes, esters, ethyls, ketones). Full-spectrum extracts contain the multitude of cannabinoids, terpenes and other phytochemicals. According to the entourage effect, phytochemicals (e.g. cannabinoids) have synergistic effects and work thereby better together with other botanical chemicals. This means that a CBD oil which contains CBD plus other cannabinoids, terpenes and phytochemicals will have a significantly higher therapeutic impact than a CBD oil containing CBD only. However, chlorophyll extraction is avoided since it gives the extract an unpleasant taste.
Step by Step
- Ultrasonic Extraction: Ultrasonic extraction can be easily performed in batch or continuous flow-through mode – depending on your process volume. The extraction process is very rapid and yields in a high amount of active compounds.
- Filtration: Filter the plant-liquid mixture through a paper filter or a filter bag to remove the solid plant parts from the liquid.
- Evaporation: For the separation of the CBD oil from the solvent, commonly a rotor-evaporator is used. The solvent, e.g. ethanol, can be recaptured and reused.
- Nano-Emulsification: By sonication, the purified CBD oil can be processed into a stable nanoemulsion, which offers superb bioavailability.
High Extraction Rate
Hielscher’s ultrasonic extractors can be precisely tuned to optimal extraction conditions – extracting the highest amount and quality from your raw material (cannabis leaves, buds, stems etc.). The ultrasound intensity is crucial when it comes to the extraction of botanical compounds such as high-quality CBD oil from cannabis. Our ultrasonicators UP400St, UIP500hdt, UIP1000hdt and UIP2000hdt are equipped with precise amplitude control, temperature sensor and time control to allow you operating under optimal conditions. The coloured touch screen and browser control make operation and monitoring simple and reliable.
Ethanol is widely used as solvent for the extraction of cannabinoids. Hielscher’s ultrasonicators open your selection of solvents drastically: water-ethanol mixture, cryogenic ethanol, ethanol, over-proof alcohol, glycerin etc.
Ethanol is a very popular solvent since it ethanol dissolve both polar (hydrophilic) and nonpolar (hydrophobic/lipophilic) substances. Mixtures of ethanol/water at different ratios can be used for ultrasonic extraction, too. The advantages of ethanol/water include reduced costs (due to less ethanol) and higher safety since less flammable. Ultrasonic extraction with cryogenic ethanol (approx. -70°C) gives very high yield and quality.
Our ultrasonic devices are designed for optimal user-friendliness, meaning that our ultrasonic extractors can be easy and safely operated. We are glad to assist our clients during their setup and give them recommendations regarding ultrasonic setting and parameters. We offer you the most suitable device – for batch and inline processing.
Advantages over CO2 Extraction
Supercritical CO2 extractors are expensive to purchase and operate. The operation of CO2 extraction is complicated and requires an expert who knows which pressures and temperatures are appropriate to obtain the desired cannabinoids and terpenes. The high pressures and high temperatures contribute significantly to the increase of costs compared to conventional liquid extraction. In comparison, ultrasonic extraction is inexpensive to buy and run, yields in high extracts, which are obtained within a few minutes. Since sonication is performed at ambient (or slightly elevated) pressure and low temperatures, the ultrasonic extraction is easy and safe to operate. Hielscher’s ultrasonic extraction are recognized and preferred for their high extraction rate, the use with various solvents, easy use and linear scalability.
In order to obtain high bioavailability and best effects of CBD, the CBD oil droplets should be administered in nanoform.
The beauty of Hielscher’s ultrasonic devices lies in their versatile utilization: Our ultrasonic systems can be used for cannabis extraction AND the production of nanoemulsions. You have to buy only one device to extract the CBD from cannabis and to process the CBD oil afterwards into a stable, highly bioavailable nanoemulsion.
Click here to learn more about ultrasonic nanoemulsification of CBD!
High Performance Ultrasonic Extractors
Hielscher Ultrasonics supplies ultrasonic extraction equipment for cannabis extraction and the emulsification of nano-formulations.
Besides their precise controllability and user-friendliness, all our ultrasonic devices are built for the 24/7 operation. Our systems are capable to deliver from low up to very high amplitudes. For the extraction of cannabinoids and terpenes, we offer special ultrasonic sonotrodes (also known as ultrasonic probes or horns) that are optimized for the sensitive isolation of high-quality active substances. All our systems can be used for the extraction and the afterward emulsification of cannabinoids.
The robustness of Hielscher’s ultrasonic equipment allows for 24/7 operation at heavy duty and in demanding environments.
Contact us today! We are glad to recommend you the most suitable ultrasonic setup for your extraction needs!
- High quality extracts
- More complete extraction
- High extraction rate
- Full-spectrum extract
- Use of various solvents
- Non-thermal (cold) method
- Rapid extraction process
- Safe and easy-to-use
- Linear scalability
- Brenneisen R. (2007): Chemistry and Analysis of Phytocannabinoids and Other Cannabis Constituents. In: ElSohly M.A. (eds) Marijuana and the Cannabinoids. Forensic Science and Medicine.
Facts Worth Knowing
Advantages of Ultrasound Extraction
Ultrasonic extraction is based on the principle of acoustic cavitation. Cavitation occurs as the results of high-performance ultrasound in liquid and is characterized by energy-dense mechanical effects, which take place in so-called hot-spots.
Ultrasonic Extraction – Cavitational Effects
When power ultrasound waves are couples into a liquid (e.g. a suspension consisting of botanical material in a solvent), the ultrasonic waves travel through the liquid causing alternating high-pressure / low-pressure cycles. During low-pressure cycles, minute vacuum bubbles (so-called cavitation bubbles) are created, which grow over several pressure cycles. At a certain size, when the bubbles cannot absorb more energy, they implode violently during a high-pressure cycle. The bubble implosion is characterised by intense cavitational forces, including micro-turbulences and liquid streams with velocities of up to 100m/s. These cavitational shear effects are also known as sonomechanical effects. Ultrasonic extraction of bioactive molecules is mainly caused by sonomechanical effects:
The extraordinary conditions of ultrasonic cavitation perforate and/or disrupt cell walls and membranes and enable greater penetration of solvent into the sample. Ultrasonic extraction achieves therefore a very rapid isolation of compounds – outperforming conventional extraction methods in shorter process time, higher yield, and at lower temperatures. As a mild (sono-)mechanical treatment, ultrasound extraction prevents the thermal degradation of bioactive compounds and outperforms other techniques such as conventional solvent extraction, hydrodistillation, or Soxhlet extraction, which are known to destruct heat-sensitive molecules. These advantages makes ultrasonic extraction the preferred technique for the release of temperature-sensitive active compounds from botanicals.
Therefore ultrasonic extraction is the preferred technique to extract bioactive molecules such as polyphenols, terpenes, essential oils and cannabinoids from the plant materials.
The extraordinary conditions of ultrasonic cavitation perforate and/or disrupt cell walls and membranes and enable greater penetration of solvent into the sample. Ultrasonic extraction achieves therefore a very rapid isolation of compounds – outperforming conventional extraction methods in shorter process time, higher yield, and at lower temperatures. As a mild mechanical treatment, ultrasound extraction prevents the thermal degradation of bioactive compounds and outperforms other techniques such as conventional solvent extraction, hydrodistillation, or Soxhlet extraction, which are known to destruct heat-sensitive molecules. These advantages makes ultrasonic extraction the preferred technique for the release of temperature-sensitive active compounds from botanicals.
Cannabinoids are naturally occurring compounds found in the Cannabis sativa plant. There are over 480 different compounds present in the cannabis plant. Cannabis (also called marijuana) an extraordinarily powerful medicinal herb. Of the wide variety of therapeutically active compounds, 85 phytochemicals are termed cannabinoids (and more might be detected). CBD and THC (tetrahydrocannabinol / Δ9-THC) are the most prominent cannabinoids. The most important distinguishing characteristic is that CBD is non-psychotropic, whilst THC shows psychoactive effects.
Cannabinoids are consumed for recreational and medical reasons.
Pharmacokinetic data of CBD:
bioavailability – Oral: 13–19%, Inhaled: 11–45% (mean 31%)
elimination half-life: 9 hours
In the USA, CBD products containing less than .03% THC, extracted from seeds or stalks of industrial hemp, are federally legal and can be legally purchased in all states, regardless of its marijuana laws.
Pharmacokinetic data of THC:
bioavailability – Oral: 6–20%, Inhaled: 10–35%
elimination half-life: 1.6–59 hours, 25–36 hours (orally administered dronabinol)
Nano-cannabinoids are cannabis oils formulated into a nano-sized oil-in-water emulsion, which offers a high bioavailability (faster uptake and increased health effects) and can therefore administered at lower dosage. Furthermore, cannabis nanoemulsions can be easily blended into medical products, beverages, edibles, and cosmetic products (e.g. creams, lotions). Since nano-emulsions are often translucent, they can be easily formulated into other products without affecting the appearance.
To obtain a high-quality nano-emulsion, droplet size, and polydispersity index (PDI), are important factors that influence the stability of nanoemulsion considerably. A high polydispersity index indicates existence of large droplets, which destabilizes the emulsion through coalescence and Ostwald ripening. A small and narrow droplet size distribution is therefore an important contributing factor for stability and a longer shelf life of the (nano- / micro-) emulsion.
Cannabis-Nanoemulsions: For hemp oil or CBD nanoemulsions, the hemp / CBD oil is mixed into a high-quality food-grade oil. Typical plant oils are MCT oil, coconut oil, avocado oil, olive oil, flaxseed oil, sweet almond oil and walnut oil. As emulsifier (surfactant, wetting agent, stabilizer) have polysorbate 80, lecithin, quillaja saponins, soy lecithin, and soap bark used successfully. Xanthan gum, pectin, or whey protein can be added additionally to improve rheology and emulsion stability.
CO2 extraction can be performed in two ways: supercritical and subcritical extraction. When CO2 is used as solvent, it has different characteristics which depend on its fluid state. Subcritical CO2 defines CO2 at the state between 5-10°C (278.15-283.15K, 41-50°F) and a pressure of between 800-1500psi (54.43-102.06atm, 5.51-10.24MPa). At this temperature and pressure, CO2 behaves as a thick fluid. When temperature and pressure conditions are increased and surpass the critical temperature (304.25 K, 31.10°C, 87.98°F) and critical pressure (72.9atm, 7.39MPa, 1,071psi), the CO2 expands in the container like a gas but with a density like that of a liquid. This is known as supercritical carbon dioxide (sCO2 or SC-CO2)).
Subcritical CO2 extraction uses low temperature and low pressure and thus takes more time. Subcritical CO2 extraction gives smaller yields and can might retain some terpenes and oils. For supercritical CO2 extraction, higher temperatures and higher pressures are applied, which can damage terpenes and other phytochemicals. For supercritical CO2 extractions, a downstream process – known as winterization – is required to remove unwanted compounds such as lipids and chlorophyll. During the winterization step, the raw extract is freezed in ethanol to separate the pure cannabinoids and terpenes from other byproducts stripped during extraction.