不同產地硫磺菌菌株的培養子實體多醣體之物化性質及抗發炎活性研究

Abstract

硫磺菌 (Laetiporus sulphureus) 屬於白肉迷孔菌科真菌，其多醣體已被證實具抗癌及抗發炎等生物活性，因多醣體的複雜性高，不同物種、萃取方法，以及不同產地所取得的多醣體在物化性質與活性上可能有差異。本研究主要目的為探討南投 (NT)、雲南 (YN)、東勢 (DS) 與豐丘 (FQ) 等產地和硫化多糖 (Sulfate polysaccharides, SPS) 及一般多糖 (Polysaccharides, PS) 的萃取方法對硫磺菌多醣體的物化性質與抗發炎活性影響。結果顯示，各產地SPS的產率依序為7.54%、9.46%、4.12%與3.48%，而PS的產率則約為1至1.5%之間。SPS比PS具有較低的總醣與較高的蛋白質含量，而硫酸根含量除FQ產地外，各產地之PS皆高於SPS。SPS的單醣組成以葡萄糖、甘露糖、半乳糖及岩藻糖為主，其分子量分布以2.80 kDa最多。在傅立葉轉換紅外光譜中SPS顯示出羥基、烷基、CHO與C=O振動、C-H、S=O、C-O-C與C-O-H等鍵結，為典型的多醣體圖譜。PS的單醣組成同樣以葡萄糖、甘露糖、半乳糖及岩藻糖為主，各組間的分子量分布相似，皆具有約10-25 kDa與500-600 kDa之分子量群，而PS的官能基種類與SPS相似，屬於多醣體的圖譜。抗發炎活性顯示所有產地之SPS與PS對一氧化氮的抑制效果皆不佳，但所有產地之SPS對TNF-α與IL-6等發炎相關因子的抑制則顯示有良好的效果。這些結果說明各產地之SPS與PS具有明顯物化性質的差異，且所有SPS對於LPS誘導RAW 264.7細胞之發炎因子具有良好的抑制效果，而PS的抑制效果則較差，這些結果皆說明不同萃取方法與產地差異對於多醣體的物化性質與活性具有不同程度的影響。由於南投產地之SPS (NTS) 比其他多醣體具有最佳的抑制TNF-α與IL-6生成效果，因此試驗進一步分析NTS的化學結構。NMR結果顯示，NTS之主鏈由α-(1→6)半乳糖與β-(1→6)葡萄糖構成，且在部分葡萄糖的3-O位置具有甘露糖與葡萄糖鏈的鍵結，而半乳糖的2-O位置則具有甘露糖與岩藻糖殘基。針對不同產地硫磺菌之研究結果表明，在硫化多醣體的萃取方法下，硫磺菌的多醣體皆表現出抗發炎活性，此結果顯示出硫磺菌多醣體在發炎治療與相關藥物開發的潛力。

Laetiporus sulphureus is a fungus belonging to the family Fomitopsidaceae. Polysaccharides extracted from L. sulphureus have been confirmed to exhibit various bioactivities, such as anticancer and anti- inflammatory. However, according to many previous studies, the structures of polysaccharides are complex, their physicochemical properties may vary depending on species, extraction methods, and even origins. This study aimed to investigate the differences in physicochemical properties and anti-inflammatory activities of L. sulphureus polysaccharides obtained from different regions (NT, YN, DS, and FQ) and extraction methods (SPS and PS). Based on the results, the yields of SPS from NT, YN, DS, and FQ regions were 7.54%, 9.46%, 4.12%, and 3.48%, respectively, while the yields of PS were approximately 1% to 1.5%. SPS had lower sugar content and higher protein content than PS. However, except FQ, the sulfate content of SPS was lower than PS. Results of monosaccharide composition showed that SPS and PS mainly consisted of glucose, mannose, galactose, and fucose. SPS from different origins had a molecular weight of 2.80 kDa, and PS of different origins had molecular weight of 10-25 kDa and 500-600 kDa. The FT-IR spectra of SPS and PS showed that all of them have hydroxyl, alkyl, formyl (–CHO), carbonyl (C=O), C–H, sulfonyl (S=O), ether (C–O–C), and hydroxyl (C–O–H) bonds. In anti-inflammatory analysis, both SPS and PS exhibited weak inhibitory effects on nitric oxide production. However, SPS from different origins possessed good inhibitory effects on TNF-α and IL-6 production. These results showed that SPS had stronger anti-inflammatory activity than PS, and the physicochemical properties showed that fruiting bodies from different locations but using the same extraction method possessed similar total sugar content, total protein content, monosaccharides composition, and functional group composition. As the SPS obtained from NT exhibited the best inhibition effects on TNF-α and IL-6 production, further experiment was performed to analyze its chemical structure. The NMR results showed that the main chain of NTS consisted of α-(1→6)-linked galactose and β-(1→6)-linked glucose, and the mannose and glucose side chains were substituted at the 3-O position of certain glucose, while mannose and fucose residues were attached to the 2-O position of galactose. According to the results, SPS from all origins exhibited anti-inflammatory activities. These findings showed that polysaccharides of Laetiporus sulphureus have potential for inflammation treatment and related drug development.