Food Chemistry and Food Development, Department of Biochemistry, University of Turku, FI-20014 Turku, Finland.
Johan Gadolin Process Chemistry Centre, Laboratory of Organic Chemistry, Åbo Akademi University, FI-20500 Turku, Finland.
Food Chem. 2019 Dec 15;301:125255. doi: 10.1016/j.foodchem.2019.125255. Epub 2019 Jul 25.
Craterellus tubaeformis (Funnel Chanterelle) is among the most abundant wild mushrooms in Finland. Three polysaccharide fractions were sequentially extracted from the fruiting bodies of C. tubaeformis, using hot water, 2% and 25% KOH solutions, respectively, and purified. The monomer composition, molecular weight, and chemical structure were determined using chromatographic and spectroscopic methods. Thermogravimetric analysis was performed as well. The hot water extract consisted mainly of high-molecular weight → 2,6)-α-Man-(1 → and → 6)-α-Gal-(1 → chains, covalently bound to proteins. The alkali extracts consisted of acidic → 6)-β-Glc-(1→, with branches of short → 3)-β-Glc-(1 → chains or single β-Glc residues. The use of alkali influenced the glycosidic linkages, molecular mass and thermal stability of the polysaccharide fractions. The use of KOH 2% increased the amount of low molecular weight polysaccharides, resulting in bimodal molecular weight distributions, with little impact on the thermal stability. Conversely, extraction with KOH 25% provided low molecular weight polysaccharides with substantially reduced thermal stability.
喇叭菌（Funnel Chanterelle）是芬兰最丰富的野生蘑菇之一。从喇叭菌的子实体中依次使用热水、2%和 25%的 KOH 溶液提取三种多糖级分，并进行纯化。使用色谱和光谱方法确定了单体组成、分子量和化学结构。还进行了热重分析。热水提取物主要由高分子量的（2,6）-α-Man-（1→和（→6）-α-Gal-（1→链组成，与蛋白质共价结合。碱提取物由酸性（→6）-β-Glc-（1→组成，带有短（→3）-β-Glc-（1→链或单个β-Glc 残基的支链。碱的使用影响了多糖级分的糖苷键、分子量和热稳定性。使用 2%的 KOH 增加了低分子量多糖的量，导致分子量分布呈双峰，对热稳定性影响不大。相反，用 25%的 KOH 提取提供了低分子量多糖，其热稳定性大大降低。
