Optimization of Vacuum-Microwave Radiation Pretreatment on Extraction of Ganoderma Polysaccharides

Abstract

A new process of vacuum-microwave (VM) radiation pretreatment for extracting polysaccharides from the Ganoderma lucidum was proposed, and the parameters were optimized by response surface methodology (RSM). The orthogonal-central composite design scheme was used and the responsive surfaces methodology of three factors and five levels was adopted, and the factors influencing the technological parameters and its interaction terms were analyzed and regressed. The optimal parameters were obtained as follows: the infiltration time of 70 min, microwave power density of 11.2 W/g, and VM irradiation time of 180 s. In consequence, the extraction yield was up to 1.775% when VM radiation was conducted in advance. Compared to the traditional hot-water extraction method, VM pretreatment can shorten the extraction time by more than a half, and the polysaccharide extraction yield was increased by 48.1%. It holds significant potential for further investigation, development, and application.