Optimization of solid-state fermentation for selective delignification of aspen wood with Phlebia tremellosa

The white-rot fungus Phlebia tremellosa can delignify aspen wood and increase the accessibility of its polysaccharides to enzymatic hydrolysis, under solid-state fermentation conditions. Fermentations at the 50 g scale were conducted to provide information for the design of larger fermentations. Agitation was not required. Forced aeration was needed for delignification of wood layers more than a few millimeters thick, but air circulation between the particles was not blocked by mycelium. Shavings were the best particles size. Sterilization of the wood was essential, but preadaptation of the inoculum to growth in wood was not. Inoculum levels as low as 2% were adequate.