Ultrasonic Pretreatment Followed by Enzymatic Hydrolysis for Extraction of Polysaccharides from Fermented Mycelia of Phellinus linteus

To develop an optimal procedure based on ultrasonic pretreatment followed by enzymatic hydrolysis for the extraction of polysaccharides from the fermented mycelia of Phellinus linteus, single factor and orthogonal array design methods were used to deal with the effects of crucial ultrasonic pretreatment and hydrolysis parameters on polysaccharide yield. Results showed that the optimization of ultrasonic pretreatment led to 3.356% polysaccharide yield, in which, the optimal values of ultrasonic power, pretreatment time and material/liquid ratio were determined to be 500 W, 20 min and 1:25 (g/mL), respectively. The optimization of enzymatic hydrolysis leading to 6.619% polysaccharide yield was achieved through the combinatorial use of cellulase at 2.5% dosage, pectinase at 2.5% dosage and neutral proteinase at 1% dosage for the hydrolysis for 120 min at pH 6.5 and 50 ℃. The combination of ultrasonic pretreatment and enzymatic hydrolysis may provide a good idea for the large-scale production of polysaccharides from the fermented mycelia of Phellinus linteus.