Differential anti-fungal effects from hydrophobic and superhydrophobic wood based on cellulose and glycerol stearoyl esters

Wood is still a widely used raw material in many fields and is surface-modified for diverse applications. Though a few studies reported the anti-fungal effect derived from enhanced hydrophobicity of wood surface, no report about the influence of superhydrophobic surface upon fungi is known and the comparison of anti-fungal effects between hydrophobicity and superhydrophobicity on wood surface has not been demonstrated. We herein addressed these aspects regarding the anti-fungal properties of both hydrophobic and superhydrophobic wood. Hydrophobic and superhydrophobic beech and pine, representing hard- and softwood were fabricated, using environmentally friendly organic materials (cellulose and glycerol). Cellulose stearoyl ester was used for dip-coating (1st layer) the wood, leading to a hydrophobic surface and glycerol stearoyl ester was used for brush-coating (2nd layer) the wood, leading to a hierarchical superhydrophobic surface. Results showed that hydrophobic and superhydrophobic woods exhibited better anti-fungal properties comparing with non-treated wood. Furthermore, differential anti-fungal effects of hydrophobic and superhydrophobic wood were observed: superhydrophobic wood could thoroughly prevent fungal attachment to treated wood, while fungi could still be found inside hydrophobic wood after anti-fungal test.