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More than 50 million tons of bark, mainly derived from pulp and wood industries, are produced annually in North America (Gupta, 2009). In Canada, only a fraction of the bark is used as an energy source by direct combustion, and the rest of the bark is incinerated or landfilled as waste (Cheng, Deng, Zhang, Riedl, & Cloutier, 2006). Both incineration and landfilling are nonsustainable avenues, whereas the combustion of bark is not ideal for energy production as it contains a high ash content that lower its heating values. Thus, the combustion of bark for energy recovery is not economically advantageous. In addition to ash, cellulose, hemicellulose, and lignin, bark also contains small amounts of bioactive compounds called extractives, which have potential to provide value-added coproducts

The continual emergence of pathogen resistance is a recurring challenge and pushes for the development of antimicrobial compounds. Here, we investigated compounds from quaking aspen trees (Populus tremuloides) as potential antimicrobial agents. Several extractions using different solvents were realized, and corresponding antimicrobial activity was tested against eight microorganisms. Results revealed that polar extraction solvents including water, ethanol and methanol gave the best extraction yields (>15.07%). Minimal inhibition concentration (MIC) and minimal bactericidal/fungicidal concentration (MBC/MFC) demonstrated that water extracts had the best antimicrobial activity by a weak to moderate inhibition of growth of all eight tested microorganisms in addition to having a bactericidal effect on three of them. The quaking aspen methanol extract also displayed antimicrobial activity but to a lower level than the water extract. Ultra-performance liquid chromatography quadrupole time-of flight mass spectrometry (UPLC-QTOF-MS) analysis led to the identification of 92 compounds, mainly polyphenols in both extracts, with 22 molecules previously known for their antimicrobial properties. According to the relative abundance, 4-hydroxybenzaldehyde (5.44% in methanol extract) and kaempferol (5.03% in water extract) were the most abundant antimicrobial compounds. Among antimicrobial molecules identified, nine were from the flavonoid family. The results of our study demonstrate the interest of using quaking aspen as source of antimicrobial compounds.

The valorization of residual forest biomass from sawmills is an economic and ecological opportunity in Que´bec. With specialized metabolites and biological activities, several residues from Que´bec's tree species could have commercial potential. This study aims to study the antimicrobial efficacy of extracts from bark residues to determine their potential as a natural disinfectant. We first performed a quantification of phenolic metabolites by colorimetric tests which showed higher flavonoids and proanthocyanidins content (>27.88 mmol catechin equivalents (CE)/100 g of bark extract and >3.90 mmol CE/100g of bark extract respectively) in black spruce extracts compared to balsam fir, quaking aspen and white birch. Extraction with water (WE) followed by fractionation with ethyl acetate yielded a fraction enriched with oligomeric proanthocyanidins (OPF). WE and OPF antimicrobial activity on Escherichia coli using the broth microdilution and the dilution-neutralization methods (AOAC 960.09) demonstrated an increased antimicrobial potency with OPF. A minimal inhibitory concentration and a minimum bactericidal concentration of 0.83 mg/mL and 4.44 mg/mL respectively as well as a microbial reduction of 4.83 log CFU/ mL (3% w/w with 10 min contact) and ‡5.09 log CFU/mL (1.5% w/w with 120 min contact time) were obtained. Compounds characterization using UPLC-QTOF-MS allowed to putatively identify nine antimicrobial compounds in the OPF. Taxifolin, dihydroxykampferol and andrographolide seemed to be associated with the increase of the antimicrobial activity of this fraction. Downloaded by 44.224.250.200 from www.liebertpub.com at 07/07/20. For personal use only. 7. Salmon D. Ressources et industries forestie`res: Portrait statistique: Québec, Ministère des Forêts, de la Faune et des Parcs; 2016. 8. Paes TL, David A, E. HR et al. Black spruce trees from fire-origin stands have higher wood mechanical properties than those from older, irregular stands.

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Quebec, a province in Canada, is well positioned in the global bioeconomy. Its regions are overflowing with forest, agricultural crops or other organic residues that can be recovered and converted into bioproducts and bioenergy. Quebec's strength has long been in the forest products industry and municipal solid waste recycling. Product diversification is now targeted by many companies and municipalities. Value chains for bioproducts and bioenergy are set in practically all of Quebec's regions. In fact, most of them have their own ''communityscale'' bioeconomy project, even if the province of Quebec itself does not have yet its own bioproducts or bioeconomy roadmap. In this paper, various community-scale bioeconomy projects are presented and discussed. The role of cities and other local stakeholders in the deployment of these projects and the focus on getting products or coproducts for local uses are also elaborated. A framework involving the positive involvement of national and regional institutions and the development of a network with local stakeholders is proposed to increase the chance of success of community-scale bioeconomy projects. Community-Scale Bioeconomy Case Studies in Quebec Community-scale bioeconomy refers to activities related to the development of bioresources production and processing supported actively by local private and public stakeholders in a