CO2 Extraction Process for Medicinal Plants

We are connected with the plants from the beginning of our existence, and fauna is vital for us to live. We rely on plants as a source of food and are always enticed by their fragrances. Since ancient times, humans have tried to capture the essence of the plant to use it in rituals, for treatment of illnesses, and other physical and spiritual needs. Spices found their place in culinary, wines and beers made everyday life less tedious, aromatics and perfumes were used as religious tools.

Scented barks, resins, aromatic vinegar, tinctures, infusions, essential oils, were essential for the medical practitioners of the early days. But from when the alchemists of the Arab world distilled the first essential oils, a long time has passed. With the advancement of technology, medicinal plant extractions are done with modern methods.

How to prepare, combine, store and use medicinal plants is one of the humans’ earliest masteries!

What is CO2 extraction?

Carbon dioxide (CO2) is a naturally occurring gas in the earth’s atmosphere. Without it, there would be no life on our planet. We, and every other animal absorb it with every breath and release it on every exhale. For plants, it is crucial for their survival as oxygen is to us. 

By being abundant and harmless to living beings, carbon dioxide shows to be the perfect solvent for the production of medicinal plant extracts. In its natural state, CO2 is a gas, which is hard to manipulate without proper equipment. Thus it was discovered fairly recently and the first CO2 extraction machine was made just 50 years ago. 

In its gas form, CO2 does not have the best solvent properties. It still offers great use to extract botanical fragrances, but it is unable to pull heavier plant compounds. Nonetheless, if we put CO2 in a supercritical state, it might just be the best extraction solvent. 

What is Supercritical CO2 Extraction?

By putting the CO2 under the pressure of at least 74 bar and heating it up to 31°C it becomes supercritical. The supercritical CO2 fluid acts as a liquid and a gas at the same time, boasting superior extraction efficiency.

3 separation vessels, each collecting a specific portion of the extract.

The main advantage of CO2 is in the advanced CO2 extraction systems. They are capable of modulating the pressure and temperature of CO2. Setting up the desired parameters enables us to manipulate its solvent properties. With the right pressure, temperature, density, and extraction time, we can target the desired compounds we want to extract. 

State-of-art CO2 extractors are also equipped with several collection vessels. Each collection vessel is set to its proper parameters, so the compounds extracted and carried by CO2 can be selectively dissolved and collected separately. This way we obtain different fractions of extracted components of different polarity, boiling point, and molecular weight successively. This means we can extract the target compounds and separate them into different portions, all in a single extraction cycle! 

Benefits of CO2 extraction for Medicinal Plant extracts

For example, we can run a subcritical CO2 extraction on the botanical material to extract just its aromatic compounds. We could use simple steam distillation to obtain the fragrance of the plant, which is still the widest used method of aromatic extraction. But when doing an extraction with subcritical CO2, the process is way quicker! Extraction with CO2 also involves much lower temperatures compared to steam distillation. High heat can ruin the delicate volatile substances, so running at lower temperatures preserves them better.

Then, by going supercritical, CO2 will remove heavier compounds like waxes, resins, and oils, which steam distillation cannot. Several beneficial substances are found in these heavier compounds and are essential for the medicinal plant extract to be effective. 

CO2 fractions
By doing a selective extraction we are able to decide which portion to incorporate in our desired product. More colour, more flavour, or more active ingredients?

Depending on the plant material we are working with, we adjust the settings of the CO2 extractor to maximise the extraction efficiency. Dialling in the correct parameters we focus on separating, isolating, and concentrating the extracted compounds. With the specific end product in mind, we then incorporate the part of the extract we find useful. The rest of the extract can be used in other formulations, processed further, or discarded.

Many solvents could be used to separate these substances from the plant matter, like alcohols and other hydrocarbons. Considering these solvents can be harmful, they have to be purged out of the extract. Especially if the end product is intended for medicine! The removal of these solvents usually alters the original matrix of medicinal plant substances and the potentially harmful solvent is never removed 100%.

Using CO2 Extraction to Extract Active Ingredients from Medicinal  Plants

As we found out, CO2, being a solvent with the best safety profile, reigns on top of medical plant extractions. The only downside is the cost of equipment, which might pose a challenge, especially for emerging businesses. 

At Essentia Pura, the quality of our products is our number one priority. Opting for CO2 extraction technology is the only way and we are proud owners of SK Skrlj MOSeS CO2 extraction system

MoSES CO2 extraction system by SK Skrlj, compact yet powerful!

Using the equipment with all the latest advances in technology we are able to extract the purest CO2 extracts of medicinal plants and manufacture active ingredients for pharmaceutical industries. At this time, we are focusing on the emerging CBD industry and strive to bring the highest quality wholesale CBD products to the market.

We are supplying the beverage industry with natural CO2 extracted flavours. For the food industry, we manufacture products such as omega3 CO2 extracts from fish and the most recent black truffles CO2 extract!

For the cosmetic industry, we offer CO2 extracted aromas, CO2 plant waxes, and CO2 etheric oils, and CO2 hydrosols.

Our mission is to obtain all our raw ingredients as locally possible, fair trade, and from organic sources!

For various extracts of herbs, spices and medicinal plants visit our website and send us a message if you have any additional questions on the matter. If you would like to take advantage of our superior CO2 extraction services, complete the web form!