Nettle Extraction – Potent Tinctures with Ultrasonics

Nettle (Urtica dioica) is a plant rich in bioactive compounds such as polyphenols, antioxidants, carotenes, and terpenoids, which are used as pharmaceutical, therapeutic and nutraceutical substances. The ultrasonic extractor is a high-efficient industry-established tool for the production of nettle extracts of superior quality.

The Benefits of Ultrasonic Nettle Extracts

Nettle leaves, flowers and stems contain a wide variety of bioactive compounds, which are used for their medicinal and therapeutic effects. Since it often would require to consume large amounts of the nettle plant in order to get the desired effects, nettle extracts are a more viable and consumer-friendly method of administration. Nettle extracts, e.g. in form of concentrates or tinctures, are an efficacious option to ingest the full spectrum of phytochemicals in a highly potent form.
Ultrasonic extraction is a mild, yet highly efficient technique to produce nettle extracts, e.g. in form of an alcoholic or water-based extract. These ultrasonically produced extracts offer a significantly stronger and more concentrated effect when compared to traditional concoctions such as single extracted compounds, macerated extracts or teas.

Solvents for Ultrasonic Nettle Extraction

For an efficient extraction of bioactive compounds from fresh or dried nettle leaves, mild non-toxic solvents such as water, aqueous ethanol or ethanol are most commonly used. Depending on the downstream processing (e.g. extract concentration by rotor-evaporation or distillation), ethanol or aqueous ethanol with higher ethanol ratio might be favorable due to the lower evaporation enthalpy of alcohol.

Case Studies: Ultrasonic Nettle Extraction Scientifically Proven

Šic Žlabur et al. (2022) investigated the effects of ultrasonic extraction as a green extraction technology. Since ultrasound-assisted extraction is characterized by high efficiency of phytochemical extraction, shorter treatment time, and a much lower environmental footprint, is a suitable and sustainable solution. In order to determine the influence of the extraction method, conventional and ultrasound (by varying two ultrasound equipment systems), time and ethanol concentration were compared regarding the extraction of specialized metabolites from nettle leaf powder. Ultrasonic extraction using a probe system, so-called probe-type sonicator or ultrasonic immersion homogenizer, significantly contributed to increase the ascorbic acid yield, polyphenolic compounds, and antioxidant capacity of nettle extracts compared to conventional extraction. In addition, with ultrasonic probe system required significantly less time for isolation of individual specialized metabolites compared to ultrasonic extraction in the ultrasonic bath. Therefore the research study comes to the conclusion that extraction with the ultrasonic probe is much more efficient in obtaining higher yields of specialized metabolites from nettle powder in a shorter time (average process duration 5–10 min) both compared to an ultrasonic bath and traditional solid-liquid solvent extraction.
 
Click here to learn more about the advantages of probe-type sonicators over ultrasonic baths (cleaning tanks)!
 

 

Florez et al. (2022) investigated the impact of ultrasonication on nettle extraction and compared the outcomes with alternative extraction techniques. In the case of total phenolic content (TPC) and ABTS•+ (2,2-azino- bis(3-etilbenzotiazolin)-6-sulfonic acid) free radical scavenging values, ultrasound extraction was the most efficient method. Best extraction yields were obtained using ultrasound treatment with water as solvent, obtaining values of 21.9 mg eq gallic acid/g dried nettle for TPC, 71.8% for %ABTS•+ and 86.6% for %DPPH• DPPH• (1,1-diphenyl-2-picrylhydrazyl). This work proves that aqueous extract of nettle leaves through the ultrasound technique is an important source of natural antioxidants and can be considered a potential alternative to synthetic antioxidants.
Florez et al. (2022) describe the advantages of ultrasonic extraction over alternative extraction methods as follows: “Traditional procedures, such as Soxhlet extraction, reflux, and maceration extraction take a long time, consume a lot of solvent, and may cause thermolabile chemicals to degrade due to the higher temperatures utilized. In recent years, other techniques have begun to be used, such as ultrasound-assisted extraction. This process allows greater penetration by the solvent into the materials to be extracted, improving mass transfer thanks to the effects of the micro-streaming. Therefore, this technique is considered an efficient extraction process that has benefits, such as reduced time, increased yields, or low temperature. It often improves the quality of the extract.”

Find Best Sonicator for Your Extraction Process

How do you select the ideal sonicator for your botanical extraction process, e.g., producing potent extracts from nettle leaves? Extracting phytochemicals from botanicals like stinging nettle requires precision and efficiency. Selecting the right probe-type sonicator is crucial for achieving optimal extraction yields, whether on a small laboratory scale or in large-scale industrial processes.
Our well-trained and long-time experienced staff appropriate probe-type sonicator will help you to select to most suitable sonicator enabling you for efficient and reproducible extraction of phytochemicals from botanicals like stinging nettle. Features such as amplitude control, process monitoring, easy operation and safety make Hielscher sonicators the preferred extraction equipment of researchers and industry professionals. Hielscher sonciators enables you to obtain optimized extraction results with outstanding efficiency and quality. Unlock the full potential of botanical resources while ensuring operational reliability and product quality using the power of ultrasound!

Design, Manufacturing and Consulting – Quality Made in Germany

Hielscher ultrasonicators are well-known for their highest quality and design standards. Robustness and easy operation allow the smooth integration of our ultrasonicators into industrial facilities. Rough conditions and demanding environments are easily handled by Hielscher ultrasonicators.

Hielscher Ultrasonics is an ISO certified company and put special emphasis on high-performance ultrasonicators featuring state-of-the-art technology and user-friendliness. Of course, Hielscher ultrasonicators are CE compliant and meet the requirements of UL, CSA and RoHs.

The table below gives you an indication of the approximate processing capacity of our ultrasonicators: