OPTIMIZATION OF FERMENTATION CONDITIONS OF GANODERMA LUCIDUM MYCELIA AND EXTRACTION CONDITIONS OF INTRACELLULAR POLYSACCHARIDES

We studied the optimal culture conditions of liquid-state fermentation of Ganoderma lucidum through flask culture,and investigated the optimal extraction conditions and methods of intracellular polysaccharides of Ganoderma lucidum mycelia.The results showed that the yield of mycelia was up to 44.8 g·L1 under the optimal fermentation conditions of fermentation time 6 days,pH 6.5,soluble starch 15 g·L-1,soybean tryptone 10 g·L-1 and FeSO4 1 g·L-1;the highest content of polysaccharides obtained by hot water extraction method achieved 17.5% under the optimal conditions of material-to-liquid ratio 1∶20,extraction time 4 hours,extraction temperature 90 ℃;and the highest content of polysaccharides obtained by enzymatic extraction method achieved 20.8% under the optimal conditions of material-to-liquid ratio 1∶20,enzyme amount 2%,and extraction time 3 hours.Based on the above result,we determine that enzymatic extraction method is the better method for extracting polysaccharides of Ganoderma lucidum mycelia.