An Integrated System of Pleurotus pulmonarius and Protaetia brevitarsis Larvae Promotes the Efficient and High-Value Utilization of Lignocellulosic Biomass

Purpose The growing world population has increased the demand for food and energy production and made the need to develop innovative approaches to convert lignocellulosic biomass to food and bio-based products particularly pressing. Methods Here, an integrated system consisting of Pleurotus pulmonarius and Protaetia brevitarsis larvae (PBL) that mediates the conversion of spent mushroom substrate (SMS) was developed, and this system permits the nutrients in three types of lignocellulosic biomass (softwood, hardwood, and shrub biomass) to be high-value utilized. Results The biological efficiency (BE) of the substrates ranged from 61.89 to 81.01%, and the total protein content in the fruiting bodies ranged from 30.68 to 39.95%. The total weight loss after mushroom production ranged from 16.68 to 23.31% of the initial substrate dry mass. These results reveal the potential of P. pulmonarius to be used for the biological pretreatment of the three types of tested biomass. The potential of PBL to utilize and convert three SMSs was investigated, and the SMS utilization rate and the SMS conversion rate varied from 66.40 to 87.64% and from 80.56 to 87.48%, respectively. PBL can efficiently convert the three SMSs into granulated frass with high organic matter content. Conclusion This new strategy for achieving the full utilization of lignocellulosic biomass by combining mushroom with PBL could aid the development of environmentally friendly and high-value-added processes. Graphical Abstract