Effect of ultraviolet radiation on polysaccharides of Ganoderma lucidum mycelia

The content of polysaccharides from Ganoderma lucidum mycelia can be increased using the method of ultraviolet（ UV） radiation introduction. The effects of different time and power of UV radiation on morphology， growth rate，and polysaccharides content of mycelia were firstly investigated. The results showed that UV radiation with low power and short time was conductive to mycelia growth and increasing polysaccharides content，and the opposite effects on those occurred under the condition of UV radiation with high power and long time. Then，the optimum UV radiation condition of increasing polysaccharides content was obtained by orthogonal test，that was， G. lucidum strains was radiated for 10 min using a UV lamp with 20 W，and the mycelia polysaccharides content can reach 9.57%，which was 3.45% higher than that of without UV radiation. In addition，the antioxidant ability of mycelia polysaccharides from G. lucidum radiated by UV under the optimum conditions was compared with that without UV radiation. The results indicated that ·OH and O2 -· scavenging capacities of the two polysaccharides were not significantly different.