【摘要】 三叶草根瘤菌H954在GMS培养基上 2 8℃培养 8d后 ,发酵液用无水乙醇分步沉淀法抽提 ,经过SephadexG 50、SephadexG 1 0、DEAE 纤维素柱层析纯化 ,并用气相色谱 (GC)、1 3C 核磁共振(NMR)和质谱分析 ,证明该菌产生环状 β ( 1 ,2 ) 葡聚糖 ,该糖是一种以葡萄糖为单体 ,通过 β ( 1 ,2 ) 葡聚糖苷健连接而成的环状分子 ,且绝大部分为中性糖 ,聚合度从 1 7到 2 2 ,其中以 1 9为主 ,分子量为 30 78D。更多还原

【Abstract】 Rhizobium leguminosarum biov.trifolii H954 has been fermented for eight days on the GMS medium.Culture supernatant is extracted by ethanol precipitation,sample is purified by Sephadex G\|50,Sephadex G\|10 and DEAE\|Cellulose chromatoraphy.Gas chromatography(GC), 13 C nuclear magnetic resonance spectroscopy(NMR)and mass spectrometry(MS) analysis indicated that the sample is cyclic,neutral glucan,and composes of glucose linked solely by 1→2 glucosidic bonds.Cyclic glucan has degrees of polymerization ranging form 17 to 22,with a degree of ploymerization of 19 as the major glucan cycles.更多还原