RHAPPLE · Novel biotechnological route for the isolation and investigation of rhamnogalacturonan-I from apple side-streams as model systems
Horizon Europe — Marie Skłodowska-Curie Actions
- Duration
- 2024-09-01 → 2026-08-31
- EU contribution
- €214,934
- Participants
- 1
- Scheme
- HORIZON-TMA-MSCA-PF-EF
Lines connect the coordinator with its partners.
Results in brief
Novel biotechnological route for the isolation and investigation of rhamnogalacturonan-I from apple side-streams as model systems
Globally, up to 40% of food is wasted, resulting in the loss of valuable nutrients and resources. Fruit and vegetable processing alone generates around 50% by-product waste, largely composed of plant cell wall polysaccharides such as pectin. Among pectic components, rhamnogalacturonan-I (RG-I) is particularly underexplored due to the difficulty of isolating it in its native, branched form. Yet, RG-I’s complex structure and its potential functional properties—such as gelling, emulsifying, and prebiotic activity—suggest a high value for food applications. Current extraction methods rely on harsh chemical or physical treatments that degrade RG-I, preventing both structural characterization and sustainable large-scale production. RHAPPLE addresses this challenge by developing a biotechnological route for the selective isolation of intact RG-I from fruit and vegetable side-streams using a fermentative approach. The project uses the yeast Kluyveromyces (K.) lactis, which can be genetically modified to secrete specific enzymes that degrade other plant cell wall polysaccharides while leaving RG-I intact. This strategy replaces chemical extraction with a mild, low-resource, and scalable process. The project’s objectives are to (1) establish K. lactis as a biotechnological platform for RG-I isolation, (2) engineer strains producing targeted enzyme sets, and (3) elucidate structure–function relationships of the isolated RG-I. By creating a sustainable process for producing high-quality RG-I and mapping its functional properties, RHAPPLE will unlock the potential of this polysaccharide as a multifunctional ingredient. The expected impact includes reducing food waste, promoting circular bioeconomy approaches, and fostering innovation in the European food and biotechnology sectors.
Data: CORDIS, © European Union
Project objective
As much as 50% of the fruits and vegetables produced globally are wasted, and so are their valuable nutrients. Fruit and vegetable waste mostly consists of primary plant cell walls, which are fibrous and recalcitrant composites of a load-bearing cellulose-cross-linking glycan network as being embedded in a more soluble matrix of polysaccharides, with pectin being the most abundant class of macromolecule within this matrix. Crude pectin extracts are used for a variety of food applications. While the functionality of pectin is sufficient for most current applications, the contribution of different pectic molecules, or structures within the same molecule, to its functionality is still poorly understood, as some structural elements are susceptible to degradation by common pectin extraction procedures. Galactose, rhamnose and arabinose, which form the rhamnogalacturonan-I (RG-I) hairy region within pectin molecules, are acid-labile, explaining the extensive debranching during conventional extraction methods and the low amounts of RG-I in current pectic ingredients. RHAPPLE aims to explore a novel biotechnological route for the selective isolation of intact RG-I from our designated model system apple pomace. We will investigate the application of yeasts that have been genetically modified to secrete a set of enzymes degrading other plant cell wall polysaccharides. We subsequently aim to provide the crucial knowledge on the structure-function relationships of RG-I and unlock its use as hydrocolloid, binding platform, and prebiotic. RHAPPLE is thus a cross-disciplinary project, involving microbiology, molecular biology and physico-chemistry tools. Our fundamental research within precision fermentation will position RG-I as one of the most promising hydrocolloids and prebiotics in the food sector and will help to raise awareness for the loss of valuable compounds by wasting plant processing by- and co-products.
Original text from CORDIS.
Participants
- AARHUS UNIVERSITET · Aarhus CCoordinatorDenmark
Links
- View on CORDIS
- DOI: 10.3030/101110529
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e5195d1ffe&appId=PPGMS
- https://ec.europa.eu/research/participants/documents/downloadPublic?documentIds=080166e523454f4e&appId=PPGMS
Data: CORDIS, © European Union