Cellulase Production by Penicillium Oxalicum Ti-11 with Traditional Chinese Medicine Residue as Substrate
Abstract PurposeThe study aims to search for efficient cellulase producer and explore the possibility of traditional Chinese medicine residue as a substrate for cellulase production, so as to realize the waste utilization of traditional Chinese medicine residue.MethodsThe cellulase-producing strain was identified through morphological and molecular biological methods. Scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the structure of traditional Chinese medicine residues before and after fermentation. The enzyme activity was determined by DNS method, and the enzyme production conditions were optimized by single factor and response surface methodology.ResultThe strain grew well in forsythia leaf residue, and the highest FPA could reach 2.06 IU/mL. In addition, the structural characteristics of traditional Chinese medicine residue that before and after enzymatic hydrolysis were characterized by SEM and FTIR. The results showed that the structure of the residue was destroyed after enzymatic hydrolysis, the damage of forsythia leaf residue was the most serious, and enzymatic hydrolysis promoted the dissolution of cellulose, lignin and hemicellulose. The enzyme production conditions of the strain were optimized by Plackett-Burman design and response surface analysis. The FPA could reach 2.79 IU/mL under the optimal conditions of FLR concentration 24.84 g/L, (NH4)2SO4 concentration 2 g/L, temperature 34.44℃, pH 6.20, rotational speed 200rpm, inoculum 6%, which was 35.44% higher than that before optimization.ConclusionsThe results showed that traditional Chinese medicine residue could be used as the induced substrate for fungal cellulase production. This study provides an idea for the low-cost production of fungal cellulase and the waste utilization of traditional Chinese medicine residue.