Enhancing enzymatic hydrolysis and fermentation efficiency of rice straw by pretreatment of sodium perborate

Abstract

In this study, we proposed a simple and effective sodium perborate (SPB) pretreatment method to enhance the enzymatic hydrolysis efficiency of rice straw (RS). The lignin removal rate reached 45.76% under the optimum pretreatment conditions of 8% SPB and 80 °C for 4 h, and the enzymatic hydrolysis efficiency of pretreated RS was 84% at a cellulase loading of 20 FPU/g RS. Through simultaneous saccharification and co-fermentation (SScF) of the pretreated RS solid with Saccharomyces cerevisiae SHY07-1, the maximum ethanol concentration was 15.29 g/L at 72 h, with a fermentation efficiency as high as 91.96%. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT-IR) analyses revealed that the RS structure was destroyed by SPB pretreatment, and lignin was effectively removed. The overall data of this study indicate that SPB pretreatment is a promising method to improve enzymatic hydrolysis and bioethanol production from RS by inoculating Saccharomyces cerevisiae SHY07-1.