Wound healing and antimicrobial activity of European tree bark extracts

Various types of wood bark have been identified to possess antimicrobial, antiviral, anti- inflammatory, and wound-healing properties (Emrich et al., 2022). This poster will present the research on wood bark extracts from Fagus sylvatica, Prunus padus, uercus robur, Pinus sylvestris, Alnus glutinosa and Betulapendula in view of their wound healing and antimicrobial properties. The extracts were retrieved using the Soxhlet extraction ethod. The minimum inhibitory concentration (MIC) assay was used to determine the effectiveness of antimicrobial agents on Cutibacterium acnes, Staphylococcus epidermidis, MRSA-Staphylococcus aureus and Escherichia coli, K. pneumoniae, P. aeruginosa. To determine the wound healing capacity a scratch assay was performed on a human keratinocyte cell line. Wound closure was measured up to 72 hours in the presence or absence of bark extracts. All bark extracts, except Prunus padus show varying degree of bacterial growth inhibition (MIC range from 67 μg/mL to 1073 μg/mL) against gram positive bacteria whereas solely Alnus glutinosa demonstrated a partial inhibition against gram negative bacteria at a concentration of 1073 μg/mL. In terms of the wound healing capacity, all bark extracts lead to a significantly accelerated wound closure (timepoint and concentration dependent) compared to untreated cells (e.g. 100% wound closure at 38 hours with Prunus padus compared to 72 hours without extract). Their combined positive effect on wound-healing and antimicrobial activity has great potential for the treatment of various skin diseases (Häsler Gunnarsdottir et al., 2023). In addition, the sustainability element is tackled by utilizing bark, considered a byproduct in the forest industry.