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用超声波将裂裥菌(Schizophyllum commune)降解后,经丙酮或乙醇分级沉淀,可得到一种多糖,命名为裂裥菌素(Schizophyllan,简称SPG),主链为β-1,3-吡喃糖,每3个糖基中的一个糖基与一个β-1,6-吡喃糖连接。SPG溶于水,成为由三条长度相仿的糖链组成棒状刚性三螺旋结构的三聚体。天然多糖在水溶液中经超声波处理后,分子量由5×10~6～7×10~6降为4.5×10~5,粘度亦下降,有利于纯化多糖以供临床使用。SPG对宿主有免疫调节作用,从而产生抗肿瘤和抗菌作用。它能保护宿主不受金黄色葡萄球菌、大肠杆菌、绿脓杆菌、结核杆菌和白假丝酵母的感染,对肺炎球菌和肠炎杆菌则无效。SPG的抗肺瘤作用中,除了能抑制同种(Allogeneic)肿瘤(如S-180、Ehrlich癌瘤和Lewis肺癌转移灶)外,也能抑制同系(Syngeneic)肿瘤(如AMC-60纤维肉瘤和RC-47膀胱癌)。在临床,
After degrading the Schizophyllum commune by ultrasonic waves, a polysaccharide is obtained by fractional precipitation from acetone or ethanol, which is named as Schizophyllan (SPG) and the main chain is β-1,3-pyran. For sugars, one glycosyl group in every three glycosyl groups is linked to one β-1,6-pyranose sugar. The SPG dissolves in water and becomes a trimer of three rodlike rigid triple helix structures consisting of three sugar chains of similar length. After ultrasonic treatment of natural polysaccharides in aqueous solution, the molecular weight decreased from 5×10~6~7*10~6 to 4.5*10~5, and the viscosity also decreased, which is beneficial to the purification of polysaccharides for clinical use. SPG has an immunomodulatory effect on the host, resulting in anti-tumor and anti-bacterial effects. It protects the host from S. aureus, E. coli, P. aeruginosa, M. tuberculosis, and C. albicans, but not pneumococcus and enterobacteriaceae. In addition to inhibiting allogeneic tumors (such as S-180, Ehrlich and Lewis lung cancer metastases), SPG also inhibits syngeneic tumors (such as AMC-60 fibrosarcoma and RC-47 bladder cancer). In clinical practice,