裂褶菌深层培养及多糖测定

为了深层培养裂褶菌Schizophyllum commune Fr.产生多糖,对产多糖的适宜培养基,最佳时间,高产菌株进行了研究。从南京灵谷寺及南京大学校园生长的裂褶菌子实体分离到3株产多糖的裂褶菌菌株,编号南大835,南大843,南大853。对南大843用6种不同培养基进行深层培养,测定和比较了多糖和菌丝产量,其结果表明黄豆粉葡萄糖液体培养基是适于裂褶菌合成多糖的培养基,能培养出密集、白色、均匀的菌球和丰富的多糖。其组成为(g/L):葡萄糖30,黄豆粉5,酵母膏2,KH_2PO_4 1,MgSO_4·7H_2O0.5。pH5.5。最适发酵条件:pH5—5.5,温度26—28℃,振速:100—110次/分,当pH降至4.9—4.7,残糖量在1%以下,5—6天可终止发酵。在培养6天的浓缩滤液中加入等体积的95%乙醇后大量白色粘稠、纤维状的多糖被沉淀下来。在上述发酵条件下,3个菌株比较结果,南大853能明显提高多糖产量,6天的培养液中多糖量可达5.5—6g/L,南大843和南大835分别是5g/L和2.8g/L。

A STUDY OF SCHIZOPHYLLUM COMMUNE BY SUBMERGED AND DETERMINATION OF POLYSACCHARIDE

In order to produce the polysaccharide of Schizophyllum commune Fr. by submerged culture technique, the suitable medium, optimal time and high-yielding strain producing polysaccharide were studied. 3 strains of S. commune which produce polysaccharide from fruit bodies of S. commune were isolated from Lingo temple and campus of Nanjing University and they were designated as Nanda 835, Nanda 843 and Nanda 853. The yields of polysaccharide and mycelium of Nanda 843 were determined and were compared by submerged culture in six different media. The experimental results indicated that he Soybean meal glucose liquid medium was found to be the preferable medium for polysaccharide synthesis by S. commune as compared to the other media. In such a medium, a dense suspension of S. commune with numerous white homogeneous mycelial pellets and abundant polysaccharide could be successfully produced. The medium composition is as following (g/l): glucose 30, soybean meal 5, yeast extract 2, KH_2PO_4 1, MgSO_4.7H_2O0.5 pH 5.5. The following optimal conditions were varified. pH 5-5.5; temperature 26-28℃;shake rate: 100-110 times/min. When pH value dropped to 4.9-4.7 residual sugar 1%, usually being 5-6 days. The white, fibrous polysaccharide could be precipitated from concentrative filtrate of 6 days-old cultures by the addition of equal volume 95% alcohol. Among the 3 strains tested it was found that Nanda 853 remarkably increase the yields of polysaccharide and produced about 5.5-6g/l in culture fluid of 6 days. The polysaccharide produced by Nanda 843 and Nanda 835 strains amount to 5 g/l and 2.8g/l respectively.