Determination of Structural Carbohydrates and Lignin in Biomass

Agriculture Sciences, Engineering and/or Technology, Natural Sciences
1 Oct, 2024 to 28 Feb, 2025
22 Jul, 2024

General information

6 months

Celignis is an innovative platform in which people highly motivated have the opportunity to think differently. In the words of our CEO, "We see huge potential for biomass to sustainably meet global energy and material needs. Through innovation, passion, and determination, we at Celignis strive to make a difference in the development of the bioeconomy."

Lignocellulosic biomass is mostly Structural Sugars and Lignin. These fractions must be quantified to elucidate the biomass potential. Structural sugars are bound in the matrix of the biomass, while the non-structural sugars can be release using accelerated solvent extraction. Lignin is a complex aromatic polymer mostly acid-insoluble. 

This position implicates a two-step acid hydrolysis to fractionate the biomass into monomeric sugars. The lignin portion is measured as acid-insoluble residue and acid-soluble lignin. The acid-insoluble residue contains ash and more likely protein, which must be considered by mass balance. The acid-soluble lignin is measured by UV-Vis spectroscopy. During hydrolysis, the polymeric sugars are hydrolyzed into monomeric forms, which are soluble in the hydrolysate. The hydrolysate is further diluted with melibiose and then quantified by our chromatography team. 

This experiment is suitable for extractives-free biomass, hence the sample needs to be previously treated or extracted by our extraction team, also known as the pre-treatment process. The intern will get experience in adhering to SOPs and quality control methods as well as evaluating the quality of data produced. The quality of the data represents the core of Celignis as we trust that with accurate data the opportunities are limitless. Results must be check and validate by the intern which will determine the effectiveness of the work done. The intern may also get involved in the Preparation of Samples prior to this procedure.


- Analytical balance, accurate to 0.1 mg.

- Convection drying oven, with temperature control of 105 ± 3°C. 6.3

- Muffle furnace, equipped with a thermostat, set to 575 ± 25 °C or equipped with the optional ramping program

- Water bath, set at 30 ± 3 °C

- Autoclave, suitable for autoclaving liquids, set to 121 ± 3 °C

- Filtration setup, equipped with a vacuum source and vacuum adaptors for crucibles

- Desiccator containing desiccant

- UV-Visible spectrophotometer, diode array, or single wavelength, with high purity quartz cuvettes of pathlength 1 cm.

- Automatic burette, capable of dispensing 84.00 mL water, optional


- Sulfuric acid, 72% w/w (specific gravity 1.6338 at 20°C) 

- Water, purified, 0.2 µm filtered

- High purity standards: D-cellobiose, D(+)glucose, D(+)xylose, D(+)galactose, L(+)arabinose, and D(+)mannose


- Pressure tubes, minimum 90 mL capacity, glass, with screw-on Teflon caps and o-ring seals (Ace glass # 8648-30 tube with #5845-47 plug, or equivalent)

- Stir rods are sized to fit in pressure tubes and approximately 5 cm longer than pressure tubes 

- Filtering crucibles, 25 mL, porcelain, medium porosity, Coors #60531 or equivalent.

- Bottles, wide mouth, 50 mL

- Filtration flasks, 250 mL

- Erlenmeyer flasks, 50 mL

- Adjustable pipettors, covering ranges of 0.02 to 5.00 mL and 84.00 mL

All analyses should be performed in accordance with an appropriate laboratory-specific Quality Assurance Plan (QAP)

From a Lab dedicated to Accelerate the Circular Bioeconomy to ensure a sustainable future by providing our customers and partners the most accurate data and innovative solutions, we encourage you to be part of our spearhead team full of dynamic and enthusiastic people that have a particular focus on technologies that can reduce the world's dependence on fossil fuels and non-sustainable practices.

**Please note that we are not able to provide any financial support for this internship**

** Please note that due to the long duration of the visa process we can only recruit candidates with a European passport. However, we are willing to listen to enthusiastic candidates with a remarkable scientific background **

No financial compensation


Biomass  Lignocellulose  Sustainable  Renewable  Bio-based  Eco-friendly  Lignin  Hydrolysis  Bioeconomy  Waste Valorization  Bioprocess Development  
English: Independent User B2
Level of Studies: 
Lab Analysis
Time Management
Quality Assurance Plan