Extraction of polysaccharide from Lentinula edodes fruit bodies using stepwise enzymic hydrolysis.

The reaction conditions for enzymic extraction of polysaccharide from Lentinula edodes fruit bodies using cellulase,pectinase and papain individually were optimized using orthogonal testing L9(34). The respective optimal conditions for extraction with cellulase,pectinase and papain were as follows: (a) cellulose concentration 0.8%,temperature 45 ℃,pH 4.5,extraction time 1 h;(b) pectinase concentration 1.0%,temperature 45 ℃,pH 3.5,extraction time 2.0 h;(c) papain concentration 1.0%,temperature 45 ℃,pH 4.0,extraction time 1.5 h. Polysaccharide was then extracted using stepwise enzymic hydrolysis whereby each of the three enzymes was used successively under the respective optimal conditions. The traditional hot water extraction method was adopted as the control. The yield of polysaccharide extracted using stepwise enzymic hydrolysis (14.17%) was 128.2%,43.71%,46.99% and 23.11% higher,respectively compared with the individual yields obtained using hot water,cellulase,pectinase and papain. UV spectrophotometry revealed that the purity of the polysaccharide,as determined by Sevag’s method,extracted using stepwise enzymic hydrolysis was higher compared to polysaccharide extracted using hot water.