Valorization of Conifer Bark by the Green Production of Useful Bioproducts for Agriculture

Bark residues generated by the forest industry are abundant in Quebec (more than 1,7 Mt anhydrous per year). The current use of these residues is mainly limited to energy production and a little to soil amendment. However, conifer bark represents an interesting source of bioproducts useful in a variety of sectors of activity. They contain a high content of various extractable compounds (flavonoids, terpenes, tannins...) with numerous biological activites of interest for various unmet needs, notably for the animal feed and potato cultivation fields. This project aims to develop fine applications for bark residues from the forest industry, more specifically for Produits forestiers Résolu (PFR) and Boisaco.

Recent work carried out by the Université du Québec à Chicoutimi (UQAC) has shown that very slightly water-soluble diterpenes present in significant quantities in conifer bark are active against Streptomyces scabiei bacteria, which is the main bacteria responsible for common potato scab. On the other hand, these barks are also rich in various phenolic compounds, often water-soluble, and notably recognized for their marked antioxidant activity.

The company Nat-Phen Nutrition is looking for antioxidant extracts for the animal feed industry and biocides for field crops. The UQAC, in collaboration with Nat-Phen Nutrition, Boisaco and PFR, is developing a green enzymatic extraction approach to obtain an aqueous fraction rich in phenolic compounds and a lipid phase rich in hydrophobic compounds. The UQAC hopes to obtain a lipid phase rich in diterpenes active against scabies and an aqueous phase enriched in antioxidant compounds sought after for animal nutrition.

It is also planned to valorize the residual plant matrix (bark having undergone the extraction process) by chemically functionalizing it in order to develop materials for the capture of industrial pollutants.

At the end of the project, PFR and Boisaco will have access to fine valorization ways for their bark, in a circular economy approach, while Nat-Phen Nutrition will be able to introduce new Quebec-based biosourced polyphenols in its range of products for animal nutrition.