This study was conducted to develop a renewable and sustainable bio-material to replace polystyrene (EPS) in fungal-mycelium-based composite using agricultural by-products. Four mushrooms (Ganoderma lucidum, Fomitella fraxinea, Phellinus linteus, and Schizophyllum commune) were cultured in an oak sawdust plus rice bran substrate to select the mushroom with the best growth. The mycelia of G. lucidum showed the best growth. To investigate the optimal mixing ratio with spent mushroom substrate (SM) and oak sawdust (OS), samples were prepared by mixing SM and OS at ratios of 50%:50%, 60%:40%, and 80%:20% (w/w). Each substrate was then inoculated with G. lucidum. G. lucidum showed the best mycelial growth of 140.0 mm in the substrate with SM and OS mixed at a 60%:40% ratio. It was also found that the substrate with SM and OS mixed at a 60%:40% ratio had the best handling properties. The compressive strength of mycelial materials inoculated with G. lucidum was in the range of 300–302 kgf mm-1, and the materials were four times stronger than polystyrene materials. These results indicate that substrates comprising spent mushroom substrate mixed with oak sawdust can be successfully upcycled to mycelium-based composite materials using G. lucidum. This represents a sustainable approach.

In order to provide basic data for preparing management standards and to verify the safety of the Chinese oak mushroom-derived moisturizing medium—which is synthesized and imported in large quantities—the presence of 321 residual pesticides, 7 heavy metals, and 3 radioactive materials was analyzed in the moisturizer samples. Examination of residual pesticides in seven moisturizing medium samples prepared using the Chinese oak mushroom and three domestic sawdust samples used for mushroom culture revealed the presence of cypermethrin and iprodione in three moisturizer samples, but the contents of these pesticides were below the standard limits. Zn was detected in ten samples, Cu was detected in nine samples, and Ni was detected in four samples, but their contents were below the standard limits. Pb, Cd, Cr, and Hg were not detected in any sample. No radioactive materials were detected in the samples. In addition, fruiting bodies of the oak mushroom were observed in each medium. Examination did not reveal the presence of any residual pesticides or harmful compounds. In this study, the use of the moisturizing medium prepared using the Chinese oak mushroom was found to be safe. As residual pesticides, heavy metals, and radioactivity—even in trace amounts—remain concentrated in the human body, continuous verification of the safety of hazardous substances and pollutants during the systematic cultivation and management of these mushrooms is required.

The fungal mycelium-based composite is a new biomaterial to replace the existing composite material. To compete with lightweight, high-performance composites represented by fiber-reinforced plastic, various physical and chemical properties and functionality must be secured. Especially, the composite material made by using mushroom mycelium (or fruting bodies) is called mushroom plastic. Currently, Ecovative, Mycoworks, and Muskin in USA and Europe are launching new products including structural materials and leathers. Products utilizing mushroom mycelium can be launched in the market for construction materials, automobile interior materials and artificial leather substitutes. In spite of this high possibility, mass production using FMBC has not yet been reported. This presentation introduces the mycelium-based materials, a material that can replace existing plastics, inorganic building materials and animal skins in an environmentally and economically viable way, and looks at the possibility of future biomaterials by summarizing recent research contents.