Enzymatic saccharification of spent wood-meal media made of 5 different tree species after cultivation of edible mushroom Auricularia polytricha

Abstract

The chemical characteristics and the suitability for enzymatic saccharification in the spent culture media (SCM) of Auricularia polytricha were examined in order to investigate the utilization of the SCM as a biomass resource for alternative energy production. Wood meals from 3 hardwood species (Quercus serrata, Betula platyphylla var. japonica, and Alnus japonica) and 2 softwood species (Pinus densiflora and Cryptomeria japonica) were used as basal culture media. Dry weight of fruiting bodies were higher in the cultural media made of B. platphylla var. japonica and A. japonica. Amount of weight loss in media showed almost the same value among the cultural media made of 5 species, except for media made of C. japonica. The amounts of the main chemical components (Klason lignin, holocellulose, and α-cellulose) in SCM showed lower values than those in wood meals (WM) and fresh media (FM). After saccharification of the media by Meiselase for 48 h, the hydrolysis weight decrease dramatically increased in SCM. The amount of glucose in SCM ranged from 10.9 to 19.2 g/100 g dry biomass. The highest amount of glucose was obtained in the SCM from B. platyphylla var. japonica. These results indicate that SCM of A. polytricha is a suitable biomass material to produce fermentable sugars for bio-ethanol production. © 2011 The Japan Wood Research Society.