Multi-perspective analyses of rice straw modification by Pleurotus ostreatus and effects on biomethane production

Multi-perspective analyses were carried out to investigate the effect of rice straw modification for 45 days by P. ostreatus on biomethane of production. The results showed that rice straw modified for 25 days achieved the highest biomethane yield of 269 mL·g^-1 VS, which was a 26.9% improvement compared with non-modified rice straw. The multi-perspective analyses demonstrated that the improvement resulted from fungal enzymatic reactions, which led to changes in the physicochemical properties of rice straw. The porosity, surface area, acetyl group abundance, degree of polymerization, and lignin degradation selectivity of rice straw modified for 25 days were optimal for enzyme adsorption. Compared with non-modified rice straw, the adsorption of cellulase and xylanase on rice straw modified for 25 days was increased by 18.8% and 58.1%, respectively, which facilitated biomethane production. The study indicated that P. ostreatus is effective for improving biomethane production from rice straw.