Dynamic high pressure microfluidization-assisted extraction and antioxidant activities of lentinan

Dynamic high pressure microfluidization (DHPM) was applied to assist the lentinan extraction. Response surface methodology (RSM), based on Box-Behnken design, was employed to optimize the DHPM-assisted extraction conditions of lentinan. Three main independent variables (DHPM pressure, ratio of water to raw material, extraction temperature) were taken into consideration. A yield of 7.200% was obtained under a modified condition (ratio of water to raw material of 65 mL/g, DHPM pressure of 147 MPa, extraction temperature of 83 °C), which matched well with the predicted value of the model. The molecular weight of the DHPM-assisted extract and hot water extract was 913,329 and 965,361 Da, respectively. Compared to the traditional hot water extraction, the lentinan extracted by DHPM assisting had better scavenging capacity of hydroxyl radical, superoxide anion free radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and nitrite. It could be concluded that the DHPM was a promising method to enhance the yield and antioxidant activity of lentinan during extraction.