• Extraction of Biomass
    Process Development
    At Celignis Biomass Lab

Background

Terrestrial plants, macroalgae (seaweed) and microalgae, are rich in a wide array of bioactive compounds. These are defined as chemicals, typically found in small amounts in biomass, that have actions in the body that can promote good health. They are different from essential nutrients (like carbohydrates, proteins, fats, vitamins, and minerals), which are needed for survival and basic biological function.

These bioactive compounds can often have antioxidant, anti-inflammatory, or anticancer properties. They can also interact with enzymes, cell receptors, or DNA, which can lead to changes in cell function and hence a potential improvement in health.

As a result, many bioactive compounds are considered to be highly valuable in the food, feed, cosmetic, and pharmaceutical industries.


These high-value constituents are typically found in the leaves, bark, flowers, roots, seeds/nuts, and fruit and vegetable parts of the plant. They are typically not a part of the lignocellulosic matrix of the plant, but instead are present as non-structural components. In particular, many high-value plant constituents can be considered to be a part of the biomass extractives.

Extractives are defined as extraneous components that may be separated from the insoluble cell wall material by their solubility in water or neutral organic solvents. Solvents of different polarities are required to remove different types of extractives. Click here to read more about biomass extractives.


Extractives in Different Biomass Types and Components

In order to efficiently remove the desired chemical, or a range of targed compounds, from the biomass, an in-depth knowledge of the biomass and desired component(s) is required to develop the most suited, sustainable and environment friendly process for optimum product yield and purity. Click the links below to read more about the different extracts that can be obtained from terrestrial and aquatic biomass.

Extractives Case Study - Hemp and CBD

Cannabinoids are an example of bioactive compounds, obtained from the extractives of hemp, that have been of particular interest in recent years. Cannabidiol has been found to have several therapeutic effects, including anti-inflammatory, analgesic, anti-anxiety, and seizure-suppressant properties.

In the period 2018-2020, as a result of the growing recognition of CBD's potential therapeutic benefits, alongside the relaxation of regulations related to hemp and CBD products in various jurisdictions (for example, the 2018 Farm Bill in the USA), there was a signficiant demand for CBD products. This led to a surge in the market price for CBD, as suppliers struggled to keep-up. However, as more farmers began growing hemp and more CBD was produced, the supply began to outstrip demand. This, along with regulatory uncertainties and issues of product quality and consistency in the industry, led to a decrease in the wholesale price of CBD.

As of 2023, the aggregate price per kilo for CBD is around 10 times less than in 2019. However, the price that a CBD product can sell for can still vary greatly, for example a CBD isolate will provide significantly higher revenue than a full-spectrum CBD oil.



There are two important lessons to be learnt from the history of hemp extracts (CBD) in the market.

1. Those producers that were first to the market in identifying CBD as a valuable bioactive compound and in developing an efficient extraction process benefitted from the early high-prices and margins as the market grew.

2. A high-quality and pure product, possible if an appropriate extraction method is designed and implemented, will allow for product differentiation and more profitable operations even in a market that is saturated.

How to Develop a Sustainable Extraction Process for Biomass


An extraction technology can be called “Green” if: the feedstock is renewable; the product is not hazardous; the catalyst or solvent used is reaction-specific and eco-friendly; the extraction process is energy and chemical efficient; and if the formation of eco-toxic by-products is avoided or minimised.

The efficient extraction of the desired component in high yield and purity is usually a multi-step process. The first step of the extraction process often involves a pretreatment of the biomass, for example by undertaking a reduction of particle size. Generally, the smaller the particle size, the higher the extraction efficiency.

However, if the particle size is too fine then this can increase the solvent-holding capacity of the biomass, which will eventually cause issues in product recovery.


Pretreatment is generally followed by extraction. The extraction method is decided based on the thermal stability, polarity, and functional groups of the compound of interest. Traditionally, maceration and percolation are used for thermo-labile compounds, while decoction, reflux extraction and Soxhlet extraction are used for thermo-resistant compounds.

Maceration and percolation are time-consuming processes, while decoction, reflux and Soxhlet extraction are known to degrade the products and reduce yields. In order to extract the desired compounds in their most natural form (non-degraded and non-modified) alternative green extraction technologies can be employed. Such green extraction approaches include: microwave, pressurised liquid extraction, ultrasound, enzymes, supercritical CO2, pulsed electric field, and hydrodynamic cavitation, among others.

At Celignis we develop bespoke extraction methods suitable for your needs with high selectivity, efficiency and low environment impact.

Other Factors to Consider in Designing Biomass Extraction Processes

While developing the extraction method for the desired product, it is important to know the regulations of the product in the market region. For example, extraction of cannabinoids is often undertaken done by using solvents or supercritical CO2.

However, as cannabinoids are considered a novel food in Europe, you cannot sell CBD extracted with these methods in the EU unless you obtain a novel food licence. However, cold-pressed oil from hemp seeds and other parts of hemp can be sold without any license requirement.


How Celignis Can Develop an Efficient Biomass Extraction Process

Identification of High-Value Chemicals

For identification, we firstly get a crude extract from the feedstock, obtained via various approaches, including pressurised liquid extraction. This extract is then profiled using our top-range QTOF-LC/MS system (Agilent iFunnel 6550), which can identify constituents to the femtogram-level, and the spectra and chromatograms reviewed by Sajna, our Bioanalysis Developer. If necessary, we can collect the relevant fractions from the LC system and confirm the identification using a number of different chemical and spectroscopic techniques. We then determine which constituents warrant extraction.



Develop an Optimised Extraction Protocol

Based on the identified chemical(s) of interest, we can then work on optimising a targeted extraction method. This method considers not only the yield of the target compound(s) but also the chemical and energy costs of the process and the implications for the downstream processing and valorisation of the solid residue. We consider a range of different extraction technologies, solvents, and process conditions.

Typically, we first optimise the extraction at lab-scale conditions and then validate the chosen set of conditions at an nehanced scale (i.e. a higher technology readiness level (TRL)).



Separation and Purification of Target Chemical(s)

We can work on a process for the separation and purification of the targeted high value extractive compounds, while considering commercial viability and environmental aspects such as solvent and energy consumption. Based on the particular bioactive compound of interest and the composition of the liquid extract, we can employ a variety of different techniques for separation and purification.

Application Testing of Extract or Separated Components

We can test the extract, or the separated compounds of interest, for a variety of different applications. The tests are custom-designed based on the extracted compound. For low molecular weight biomolecules (non food and feed), bioactivity tests, anti-microbial tests, UV absorbance properties, surface activities, and emulsion forming abilities can be tested. For the food and feed related extract fractions, such as proteins and carbohydrate polymers, nutritional properties, anti-nutritional compounds, emulsification, gelation, foaming (together with bioactive properties, in vitro digestibility etc.) are tested.

Technoeconomic Analysis of the Process

The Celignis team, including Oscar our chief TEA expert, can undertake a detailed technoeconomic analysis of the developed process. We apply accurate and realistic costing models to determine the CAPEX and OPEX of simulated and pilot scale processes which are then used to determine key economic indicators such as IRR, NPV and payback periods.

Our sensitivity analyses can assess the effect of variable costs and revenues, a particularly important aspect to consider given that the sale prices for some bioactive compounds can vary significantly according to their purity and market conditions.

Our preferred approach is to include TEA studies at each stage of the development of the extraction bioprocess, so that the process can be optimised in a commercially-relevant way, followed by a more detailed TEA after the process has been optimised and tested at higher TRL levels.

Click here to read more about the technoeconomic analysis (TEA) services offered by Celignis.

 


Bioprocess Biomass Extraction Projects - Case Studies

Betulin - UNRAVEL Project

Celignis worked extensively on biomass extraction and the purification of bioactive chemicals in the CBE/BBI project UNRAVEL where the extractives of 25 feedstocks were profiled using our QTOF-LC/MS system. We identified betulin in birch bark as the most attractive compound and subsequently worked on developing an optimised extraction protocol and an isolation/purification process scheme that offered several advantages, in terms of sustainability and safety, over the current art. Click here for a news article on this work.




SteamBioAfrica Project

We are also using employing our compositional analysis and purification expertise in the Horizon Europe project SteamBioAfrica where we evaluate and process the liquid condensate obtained from the steam torrefaction process and consider market applications for its constituents, fractions, and derivatives.

Celignis is testing the separation of acids, phenolics, and aldehydes for their potential to be used as high value bioactive compounds and biopesticides.



Bioactives Profiling of Tropical Trees

Celignis undertook detailed analysis of a wide variety of tropical hardwood trees for a client. This involved characterisation of different anatomical fractions (e.g. stem wood, bark, foliage). There was a particular focus on the composition of the extractives of these feedstocks. We used our QTOF-LC/MS system to profile the diverse and complex array of bioactive compounds present in the samples. We then evaluated the identified compounds and selected key chemicals that could be of high potential value for sale in different markets. We then undertook a review of these compounds, considering their potential value in various markets, the processes that could be required for their separation and purification, and whether other compounds could also be obtained as part of the extraction/separation process. The final output of the project was a list of top feedstocks and chemicals for future bioprocess development.



 



How our Bioprocess Development Services Work

Our Bioprocess Development Services can work on the evaluation and optimisation of a particular node in the biomass processing technology or can involve the development of a bespoke vertically-integrated technology for your chosen feedstock and/or product. Click here to see how our Bioprocess Development Services work and how we devise and undertake a project.

With regards to the extraction of bioactives from biomass, the Celignis Bioprocess team members with the most experience in undertaking such projects are listed below. Feel free to contact them to discuss potential projects.

Lalitha Gottumukkala

Founder of Celignis Bioprocess, CIO of Celignis

PhD

Has a deep understanding of all biological and chemical aspects of bioproceses. Has developed Celignis into a renowned provider of bioprocess development services to a global network of clients.

Dan Hayes

Celignis CEO And Founder

PhD (Analytical Chemistry)

Dreamer and achiever. Took Celignis from a concept in a research project to being the bioeconomy's premier provider of analytical and bioprocessing expertise.

Sajna KV

Bioanalysis Developer

PhD

Our Biomass Detective! Designs, tests, optimizes and validates robust analytical methods for our bioprocess development projects. Such bespoke analysis is key to developing an optimised bioprocess.



Other Celignis Services for Bioprocess Development

Global Recognition as Bioprocess Experts

Celignis provides valued services to over 1000 clients. We understand how the focus of bioprocess projects can differ between countries and have advised a global network of clients. We also have customs-exemptions for samples sent to us allowing us to quickly get to work no matter where our clients are based.

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Pretreatment

The choice of pretreatment method varies with the type of biomass and the end-product requirements. At Celignis we can determine the most suitable pretreatment for your feedstock and determine the optimum conditions in lab-scale trials followed by higher TRL scale-ups.

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Hydrolysis

For the hydrolysis of lignocellulosic biomass to monomeric sugars either chemical or biological approaches can be used. At Celignis Bioprocess we can use both methods at scales ranging from flask-level to 100-litres. We have particular expertise in the optimisation of conditions for enzymatic hydrolysis.

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Enzymes

Enzymes are biological catalysts that have a wide variety of applicaitons in the bioeconomy, ranging from the liberation of sugars from lignocellulosic biomass to the functionalisation of biomass-derived chemicals and materials for higher-value applications. We are experts in the design and use of enzymatic approaches.

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Fermentation

Development of fermentation processes requires knowledge of an array of important factors including: biomass, the microbes used, nutrient media, and fermentation conditions. We're experienced in many fermentations and can help you determine and optimise yields of an array of different fermentation products.

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Downstream Processing

How the various outputs (solid and liquid) of a bioprocess are dealt with is often overlooked until later in bioprocess development, leading to excessive costs and complications. We consider and tackle these issues, and others such as product recovery, early-on as being integral to the bioprocess.

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Lab-Scale Optimisations

We consider that optimising a bioprocess at the lab-scale is the most cost-effective approach to explore a range of different scenarios in search of optimal process conditions. Based on the outputs of these experiments we can then test the chosen set of conditions at higher TRL levels.

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TRL Scale-Up

At our dedicated Celignis Bioprocess laboratories we have all the necessary upstream and downstream apparatus to undertake bioprocess projects up to a tehcnology readiness level (TRL) of 6, with reactor and processing capacities of up to 100 litres.

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Technoeconomic Analyses

Our technoeconomic experts can evaluate your bioprocess, considering various scale, technology, and feedstock options. We apply accurate costing models to determine CAPEX/OPEX of simulated and pilot-scale processes which are then used to determine key economic indicators (e.g. IRR, NPV).

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Biobased Chemicals

A large array of chemicals and materials are possible from biomass and wastes. These can involve chemical or biological approaches, or a combination of the two. Based on your desired end-product we can design and test the most appropriate bioprocess.

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From Process Refinements to an Entire New Process

We work closely with you to understand your objectives and timelines. We then propose a project, usually covering a series of deliverables and stage-gates. Often our projects involve optimising conditions at the lab-scale before replicating the conditions at higher TRL levels.

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Research Collaborations

Celignis is active in several bioprocess research projects. These include projects funded by the EU's CBE-JU, with Celignis being a Full Industry Member of the BIC. We're open to participating in future collaborative research projects where our extensive infrastructure and expertise in bioprocesses can be leveraged.

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