Abstract:

Objective: To develop an optimized enzymatic method for extracting polysaccharides from Tricholoma matsutake
with a combination of cellulase, pectinase and neutral protease and to evaluate the antioxidant activity in vitro of the
extracted polysaccharides. Methods: On the basis of single-factor experiments, a four-factor, three-level Box-Behnken
design was utilized for the mathematical modeling of polysaccharide yield as a function of material/water ratio, medium
pH and hydrolysis time and temperature. This was followed by response surface analysis of the developed mathematical
model. The antioxidant activity of Tricholoma matsutake polysaccharides was determined by pyrogallol autoxidation and
free radical-scavenging assay. Results: The optimum condition for the extraction of Tricholoma matsutake polysaccharides
were found to be hydrolysis at 35 ℃ for 71 min with a material/solvent ratio of 1:40 (g/mL) at pH 5. Under these conditions,
the model-predicted and experimentally measured values of polysaccharide yield were 7.06% and 6.95%, respectively,
revealing a relative error of only 1.56% between them. The Tricholoma matsutake polysaccharides had a strong capacity to
scavenge superoxide anion (IC50 = 0.565 mg/mL) and DPPH free radical (IC50 = 0.454 mg/mL). Conclusion: The proposed
extraction method is efficient, simple and applicable for the extraction of polysaccharides form Tricholoma matsutakes and
the extracted polysaccharides have significant antioxidant capacity in vitro.

Key words: Tricholoma matsutake, response surface analysis, polysaccharides, extraction process, antioxidant effect