我們先前的研究證實黑木耳熱水萃取物 (AACE) 具有免疫刺激的功能；可活化巨噬細胞趨向M1功能表現型。AACE之不同分子量區分物的免疫刺激效力有很大的差異，分子量為10-50 kDa的區分物 (F2) 具有最高的免疫刺激功能，且可提升巨噬細胞的抗癌效力，具有作為癌症免疫療法膳食輔佐劑之潛力。多醣是大多數食用真菌的主要免疫刺激功能成分。因此，本研究進一步分析F2中多醣組成分之特性。利用高效液相層析 (HPLC)、超高效能液相層析串聯質譜 (UPLC-ESI-MS/MS) 以及核磁共振光譜 (NMR) 測定單醣組成及糖 鍵結型態。結果顯示，F2的主要組成單醣包括：葡萄糖酸、甘露糖、葡萄糖、木糖、鼠李糖以及N-乙醯胺基葡萄糖，而這些單醣也存在於分子量高於10 kDa的區分物中。分子量小於10 kDa的區分物 (先前證實不具免疫調節功效) 則未檢測出甘露糖及葡萄糖酸。F2所含葡萄糖酸、甘露糖、葡萄糖、木糖、鼠李糖和N-乙醯胺基葡萄糖之莫耳比率為1.0：5.6：5.8：6.4：6.9：19.0。與AACE其他的區分物相較，F2區分物具有最高N-乙醯胺基葡萄糖莫耳比率。核磁共振光譜顯示，F2區分物中的多醣結構推測具有-2)[β-D-GlcA-(1-3)β-D-Glc-(1-3)][α-D-GlcNAc-(1-4)]-α-D-Man-(1-2)β-D-Xyl-(1-2)α-D-Rha(1-，且具有α-D-Man-(1-2)β-D-Xyl-(1-2)α-D-Rha鍵結的主鏈。本研究結果提供黑木耳免疫刺激成分重要基本化學結構特性，有利於相關保健產品的研究開發。

Auricularia auricula-judae hot water extract (AACE) was previously demonstrated the immune-stimulating effects by initiating macrophage activation toward M1 phenotype. The subfractions of different molecular weight of AACE exhibited different potency in the immune stimulation. The components of molecular weight between 10 to 50 kDa, assigned as F2, exhibited the highest capability in the immune stimulation which associated with increase of anti-cancer efficacy of macrophages and might be a potential dietary adjuvant for cancer immunotherapy. Polysaccharides are major immunostimulating components of most species of edible fungi. Hence, in the present study, the characteristics of polysaccharides contained in the F2 fraction of AACE were further elucidated. The monosaccharide compositions and glycosidic linkages were determined using high performance liquid chromatography (HPLC), ultraperformance liquid chromatography-electrospray tandem mass (UPLC-MS/MS) spectrometry and nuclear Magnetic Resonance (NMR) spectroscopy. The results indicated that F2 fraction contained mainly gluconic acid, mannose, glucose, xylose, rhammnose and N-acetylglucosamine, whereas mannose and gluconic acid were not detected in the fraction of molecular weight lower than 10 kDa that was previously demonstrated to have limited immune-modulating activity. The F2 fraction contained gluconic acid, mannose, glucose, xylose, rhammnose and N-acetylglucosamine in a molar ratio of 1.0:5.6:5.8:6.4:6.9:19.0 and had the highest molar ratio in N-acetylglucosamine compared with the other subfractions of AACE. NMR spectroscopy revealed the presence of the glycosidic linkages of -2)[β-D-GlcA-(1-3)β-D-Glc-(1-3)][α-D-GlcNAc-(1-4)]α-D-Man-(1-2) β-D-Xyl-(1-2)α-D-Rha(1- and main chain of α-D-Man-(1-2)β-D-Xyl-(1-2)α-D-Rha in F2 components. Our study provides fundamental information required for chemistry study and nutraceuticals development for the immunostimulant components of A. auricula-judae.