Jury

Rapporteur - Dr. Gabriel Paes, INREA/URCA Reims, France
Rapporteur - Prof. Craig Faulds, University of Aix Marseille, France
Examiner - Prof. Catherine Rayon, University of Picardie Jules Verne, Amiens, France
Examiner - Dr. Brigitte Chabbert, INRAE/FARE, Reims, France
Chairman of the jury - Dr. Anne Harduin Lepres, University of Lille, France

Thesis Director - Dr. Anne-Sophie Blervacq, University of Lille, France
Former thesis supervisor - Prof. Simon Hawkins, University of Lille, France
Thesis co-director - Dr. Steve Arscott, CNRS/IEMN, France
Thesis supervisor - Dr. Sébastien Grec, University of Lille, France

 Summary:

"Flax (Linum usitatissimum L.) is a sustainable alternative to synthetic fibres in textiles and composites. The fibre extraction process begins with retting, during which micro-organisms break down the pectic substances that bind the fibres to the stalk. This biological process depends on many factors and introduces variability into fibre batches. This thesis (FlaxTronic, PEARL I-site) aims to help standardise flax retting by proposing a possible sensor-based system for real-time decision-making (Agriculture 4.0). The main objectives are to understand the biology of retting using enzymology, chemistry and metaproteomics, vibrational spectroscopy (FT-IR) and to assess stem colour changes as non-invasive markers. The main results are as follows: metaproteomics has made it possible to identify carbohydrate-active enzymes (CAZymes) and micro-organisms involved in cell wall degradation, while FT-IR spectroscopy and colour spectrophotometry could provide valuable monitoring tools for predicting the development of retting".

Abstract:

"Flax (Linum usitatissimum L.) represents a sustainable alternative to synthetic fibres in textiles and composites. The fibre extraction process begins with retting, during which microorganisms decompose the pectic substances that bind the fibres to the stem. This biological process depends on many factors and introduces variability in fibre batches. This thesis (FlaxTronic, PEARL I-site), aims to help for standardizing flax dew-retting by proposing a possible sensor-based system for real-time decision-making (Agriculture 4.0). Key objectives include understanding the biology of retting by using enzymology, chemistry, and metaproteomic; vibrational spectroscopy (FT-IR); and assessing stem color changes as non-invasive markers. As the main results, metaproteomics identified carbohydrate-active enzymes (CAZymes) and microorganisms involved in cell wall degradation, while FT-IR spectroscopy and color spectrophotometry might provide valuable monitoring tools to predict retting achievement.