Conversion of spent Juncao Substrate into reducing sugar using a one-step method

In order to improve the conversion efficiency of Spent JUNCAO SUBSTRATE (SJS) into reducing sugar and improve the utility value of SJS, a one-step method was studied in this study. Three treatment methods were designed to select the optimal one-step method, including diluted sulfuric acid (0.5 to 4% w/v, 50 to 121°C, 1 h), sodium hydroxide (0.5% to 2% w/v, 50°C to 121°C, 1 h), and hot water (50°C to 121°C, 1 h). The influence of different treatment conditions on SJS was analyzed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The results showed that the highest yield for reducing sugar was 243.8 g/kg using 4% dilute sulfuric acid as a treatment at 121°C, with the strongest hemicellulose and cellulose degradation of SJS compared to untreated SJS. Overall, a one-step method of using diluted sulfuric acid without pretreatment was a promising approach for the SJS lignocellulose conversion to reducing sugar.