Exopolysaccharide produced by a yeast Papiliotrema flavescens isolated from wine grape berries of Champagne vineyard, was investigated for both chemical and functional characterization. SEC-MALLS and colorimetric assay analyses showed that EPS is high MW heteropolymer (2.37×10⁶ g/mol) majorily consisted of mannose, glucose, xylose and glucuronic acid as monosaccharide constituents, with two substituents (sulphate and phosphate groups), and a minor protein moiety. Structural enchainment of these carbohydrates based on methylation, GC-MS and NMR analyses revealed a linear main backbone built up of α-(1→3)-D-mannopyranosyl residues on which are branched side chains consisted of single β-D-glucopyranosyluronic acid residue and β-(1→2)-xylopyranoses (2-5 residues). Suggestion of some xylopyranose side chains containing a mannose residue at nonreducing terminal end was also proposed. This is first report on exopolysaccharides from the grape Papiliotrema flavescens yeast with such structural characteristics. Furthermore, investigations for valuating the application performance of these EPS in relation with their structural features were carried out in 8% alcohol experiment solutions. Very exceptional viscosifying and foaming properties were reported by comparison with commercial biopolymers as Arabic, gellan and xanthan gums. The intrinsic properties of the natural biopolymer from this wild grape-associated Papiliotrema flavescens yeast make it potential candidate for use in various fields of biotechnology applications.

中文翻译：

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来自野生葡萄相关担子菌酵母 Papiliotrema flavescens（以前称为 Cryptococcus flavescens）的粘性胞外多糖的结构和发泡特性。

研究了从香槟葡萄园的酿酒葡萄浆果中分离出的酵母Papiliotrema flavescens产生的胞外多糖的化学和功能表征。SEC-MALLS 和比色法分析表明 EPS 是高分子量杂聚物 (2.37×10 ⁶g / mol）主要由甘露糖，葡萄糖，木糖和葡萄糖醛酸作为单糖成分组成，具有两个取代基（硫酸盐和磷酸盐基团）和少量蛋白质部分。基于甲基化、GC-MS 和 NMR 分析的这些碳水化合物的结构链揭示了由 α-(1→3)-D-吡喃甘露糖基残基构成的线性主链，其上的支链侧链由单个 β-D-吡喃葡萄糖醛酸组成残基和 β-(1→2)-吡喃木糖（2-5 个残基）。还提出了一些在非还原末端含有甘露糖残基的吡喃木糖侧链的建议。这是关于葡萄Papiliotrema flavescens的胞外多糖的首次报道具有这种结构特征的酵母。此外，在 8% 酒精实验溶液中进行了评估这些 EPS 与其结构特征相关的应用性能的研究。与商业生物聚合物如阿拉伯胶、结冷胶和黄原胶相比，报告了非常出色的增粘和发泡性能。来自这种与野生葡萄相关的Papiliotrema flavescens酵母的天然生物聚合物的内在特性使其成为生物技术应用各个领域的潜在候选者。