巴西洋菇菌絲水溶性多醣之劃分與理化特性

Abstract

巴西洋菇（Agaricus blazei Murill）是一種食藥兼用的菌菇，其子實體與菌絲發酵物之多醣區分已被證實具有免疫調節和抗腫瘤之生理活性。本研究目的在針對巴西洋菇菌絲發酵物中之水溶性多醣進行劃分純化，單離出具代表性之活性多醣，並對其特性做探討。結果顯示，巴西洋菇菌絲發酵物之水溶性粗多醣依電荷的差異，以陰離子交換樹脂(DEAE)劃分為五種區分，包括中性多醣(CP-FⅠ)、低蛋白含量多醣(CP-FⅡ)與高蛋白含量酸性多醣(CP-FⅢ)，及多醣蛋白複合體(CP-FⅣ,CP-FⅤ)，其中CP-FⅢ、CP-FⅣ和CP-FⅤ區分具有顯著刺激小鼠巨噬細胞株RAW 264.7產生TNF-α之活性。若以蛋白分解酵素和trichloroacetic acid (TCA) 處理水溶性粗多醣，則粗多醣中分別有63.5% 和88.5% 蛋白質會被除去，但CP-FⅢ、FⅣ 和FⅤ之蛋白質仍無法完全去除。活性區分CP-FⅢ之單糖組成以甘露糖和半乳糖為主，並含有葡萄糖、阿拉伯糖和岩藻糖以及另外含3.5％ 醛醣酸與3.1％蛋白質；分子量398.8 kDa，分子量分散度為3.6，因此依據分子量分成CP-FⅢ-A (442.1 kDa)、CP-FⅢ-B (154 kDa) 和CP-FⅢ-C (27.4 kDa) 三區分，CP-FⅢ-A區分糖組成以半乳糖、阿拉伯糖和甘露糖為主，並且含有顯著的活性特徵糖岩藻糖7%；CP-FⅢ-B區分以甘露糖、半乳糖和阿拉伯糖為主；CP-FⅢ-C區分以甘露糖、半乳糖和葡萄糖為主。因此由以上結果推論，巴西洋菇發酵產物中具免疫活性之多醣為一具有顯著岩藻糖之特徵與兩種多醣蛋白複合體。

Agaricus blazei Murill, is an edible and medicinal mushroom. Literatures have shown that polysaccharides isolated from A. blazei contributed its immunomodulating and antitumor activities. In this thesis, the features of active polysaccharides from A. blazei mycelia fermentation products were studied. Using DEAE-Toyopearl 650M, we separated water-soluble crude polysaccharides from A. blazei Murill mycelia fermentation products into five fractions: neutral polysaccharides (CP-FI), low protein containing polysaccharides (CP-FⅡ), rich protein containing acid polysaccharides (CP-FⅢ), and two polysaccharide-protein complexes (CP-FⅣ and CP-FV). In vitro study, three fractions (CP-FⅢ, CP-FIV, and CP-FV) can significantly stimulate mouse macrophage RAW 264.7 to release TNF-a. The chemical characteristics of CP-FIII were as follows: monosaccharide composition, mannose: glucose: galatose: arabinose: fucose (45：10：30：12：3); uronic acid content, 3.5%; protein content, 3.1%; weight-average molecular weight (Mw), 398.8 kDa; polydispersity, 3.6. According to their molecular weight, FIII was further divided into three fractions: CP-FⅢ-A (442.1 kDa), CP-FⅢ-B (154 kDa) and CP-FⅢ-C (27.4 kDa). Fraction CP-FⅢ-A mainly consisted of galactose, arabinose, mannose and fucose; fraction CP-FⅢ-B mainly consisted of mannose, galactose and arabinose: fraction CP-FⅢ-C mainly consisted of mannose, glucose and galactose. The results indicated that the polysaccharides had bioactivity of TNF-a stimulation on RAW 264.7, a rodent macrophage cell line, were a fucose containing polysaccharide with high molecular weight, and two other protein-glycan complexes.