The synergistic utilization of plantation forestry wastes: Edible fungi cultivation coupled with hemicellulose extraction by liquid hot water

Abstract

A two-step statistical method was developed with two main objectives. One objective was to utilize plantation forest wastes for edible fungi (Pleurotus ostreatus CICC 14012) cultivation and the second was to maximize the laccase activity in the substrates to facilitate hemicellulose extraction. A total of eight forestry wastes were studied using this method. Among these, Pinus massoniana sawdust, Acacia confusa leaves, and Populus tomentosa leaves were selected and optimized to formulate an ideal culturing substrate. As a result, a laccase activity of 125.7 U/g and mycelium growth rate of 1.19 mm/d were achieved with a 30-d cultivation period and without the addition of foodstuffs or agricultural residues. The physical and chemical changes in the cultivated substrate were measured through a combination of morphology and spectroscopy analyses. The findings led to the selection of a liquid hot water treatment, which was optimized through comparative analysis among different conditions. With this technique, a maximum hemicellulose recovery ratio of 68.8% was achieved with treatment at 170 °C for 50 min. The number average and weight average molecular weights of the extracted hemicellulose were 1920 and 4289, respectively.