研究業績

Although spent mushroom substrates (SMSs) are considered to be candidate bioenergy feedstocks, there are large variations in the components and structural characteristics of SMSs. To elucidate the most important characteristics of SMSs for bioenergy production, we examined nine SMSs for their ethanol, hydrogen, and methane fermentation capacities, and analyzed their major components and microstructures. Although the lignin content was similar (25 % to 27 %) in six of the nine SMSs, their ethanol productivities varied (0.05–0.14 g/g holocellulose). The microstructure of the SMSs also varied greatly; fibrous to smooth surface. It was suggested that ethanol productivity was strongly influenced the microstructure other than lignin content. Of note, the SMS of Ganoderma sinense exhibiting fibrous surface showed ethanol and hydrogen fermentation yields (98 and 103 %) that were equivalent to those of Avicel, and approximately 70 % methane fermentation capacity, thus the SMS of G. sinese is considered to be a good candidate bioenergy feedstock.