Overview
Acorn4MED - Valorisation of Acorn Forest Residues for Biomedical Applications was a pilot research and innovation project dedicated to valorising acorns as a raw material for high-value applications.
The project combined expertise in forest-resource valorisation, chemical characterisation, natural-compound extraction, biomedicine and product development. By using acorn kernels and shells, Acorn4MED sought to identify bioactive compounds with potential applications in the cosmetic and biomedical fields. Led by Tech4MED in collaboration with the Mountain Research Centre at the Polytechnic Institute of Bragança and LandraTech, the project contributed to creating new opportunities for the valorisation of an endogenous resource from Trás-os-Montes.
Context and Identified Problem
The Quercus woodlands of Trás-os-Montes produce significant quantities of acorns every year. However, a considerable proportion of this resource remains economically unexploited in a region affected by forest abandonment, low population density and limited value creation from available natural resources. The food use of certain acorn species is restricted by their high tannin content, which causes bitterness and astringency. Nevertheless, these phenolic compounds, together with lignin, lignosulfonic acid and other components present in the kernel and shell, have characteristics of potential technological and bioactive interest.
Acorn4MED transformed this limitation into an opportunity by investigating the extraction, characterisation and application of acorn compounds and by-products within a circular-bioeconomy and whole-resource valorisation approach.
Objectives
Acorn4MED’s main objective was to develop an acorn valorisation chain focused on obtaining compounds with potential cosmetic and biomedical applications. The project aimed to:
- Create a regional network of producers, forest owners and acorn suppliers;
- Ensure the collection, selection and preparation of the raw material;
- Characterise the chemical and nutritional profiles of acorn kernels and shells;
- Develop and optimise processes for extracting tannins, lignin and other compounds;
- Assess the cytotoxicity and biological compatibility of the resulting compounds;
- Study antioxidant, antimicrobial, anti-inflammatory, anticancer and antityrosinase properties;
- Develop microencapsulation and controlled-release systems;
- Select the compounds and formulations with the greatest potential;
- Develop experimental prototypes for cosmetic and biomedical applications;
- Define business models and strategies for exploiting the results;
- Create a supply chain for the valorised compounds;
- Establish scientific and industrial partnerships supporting further development.
Scientific and Technological Development
The project was organised into four complementary areas.
1. Regional supply network
A network of forest owners and acorn suppliers was established in Trás-os-Montes to provide the raw material required for the research activities and prepare a future supply chain. The collected acorns were selected, dried and processed, allowing the kernel and shell fractions to be separated and prepared for characterisation and extraction trials.
2. Characterisation and extraction of bioactive compounds
Acorns from different Quercus species, including oak and cork oak, were studied. Their kernels and shells were characterised in terms of moisture, protein, fat, fibre, carbohydrates, organic acids and phenolic compounds. Alcohol-based extraction protocols were developed and optimised for tannins and other shell compounds. Initial work recorded approximate extraction yields of 13% for oak shells and 33% for cork-oak shells, demonstrating the potential of this by-product as a source of natural compounds.
3. Biological assessment and formulation development
The resulting compounds were assessed through laboratory cytotoxicity and bioactivity tests. Tannins, lignin, lignosulfonic acid and acorn-shell extracts were studied using cell cultures and different microbiological models. Cytotoxicity testing was performed according to ISO 10993-5. Antimicrobial tests were also conducted using Pseudomonas aeruginosa and Staphylococcus aureus, including clinical isolates. The project assessed other bioactive properties and developed encapsulation systems designed to protect the compounds and provide controlled release.
4. Validation and value-chain development
The compounds and formulations with the greatest potential were selected for the development of experimental prototypes. Business models, potential markets and collaboration opportunities with scientific and industrial organisations were also assessed. This component aimed to bring laboratory results closer to future commercial applications in the cosmetic and biomedical sectors.
Impact and Contribution
Acorn4MED contributed to diversifying acorn applications by demonstrating that this resource can be valorised beyond human food and animal feed.
By studying compounds found in the kernel and shell, the project promoted more integrated use of the raw material and strengthened a circular-economy approach in which materials previously considered waste can be transformed into resources for new applications. The project’s main contributions included:
- Valorisation of an underused endogenous forest resource;
- New opportunities for forest owners and producers;
- Reduction of waste associated with acorns and their shells;
- Development of knowledge concerning natural forest-derived compounds;
- Stronger connections between the bioeconomy, cosmetics and biomedicine;
- Greater cooperation between companies and scientific institutions;
- Support for higher-value activities in Trás-os-Montes;
- Contribution to the management and preservation of Quercus woodlands;
- Creation of a foundation for future bio-based products and processes.
The project therefore explored a new value chain based on the sustainable use of acorns and the transformation of their by-products into compounds of technological interest.
Project Information
Programme: Promove Programme 2020 - Innovative Pilot Projects
Application Code: PV20-00038
Project Title: Acorn4MED - Valorisation of Acorn Forest Residues for Biomedical Applications
Total Investment: €149,329.32
Funding from the “la Caixa” Foundation: €111,938.00
Consortium co-funding: €37,391.32
Funding Rate: 75%
Duration: 36 months
Start Date: 01/04/2021
End Date: 31/03/2024
Coordinator: Tech4MED
Consortium: Mountain Research Centre - Polytechnic Institute of Bragança and LandraTech
Status: Completed