Thalli of the endemic epiphytic New Zealand red seaweed Pyrophyllon subtumens contain a high level of xylose and a notable amount of arabinose but the polysaccharide has not been characterised.

The linkage/substitution of individual sugars within the water-soluble polysaccharide extract and various derivatives were determined by chemical and spectroscopic methods.

No 3-linked sugars nor any d-galactose were found, which excluded agar-, carrageenan- or mixed 3-linked/4-linked β-d-xylan-type polysaccharides found in many other red macroalgae. Instead, the polysaccharide backbone contained predominantly 4-linked β-d-xylopyranosyl, 4-linked 3,6-anhydro-l-galactopyranosyl and 4-linked l-galactopyranosyl units. Some of each type of sugar were naturally sulfated at various positions. Some xylosyl units were substituted at the 2- or 3-position with l-arabinosyl units. The polysaccharide is complex and likely contains a range of structures. However, partial sequencing was successfully used to recover and identify a novel disaccharide 4-O-d-xylopyranosyl-3,6-anhdydro-l-galactopyranose, which indicates a unique →4)-β-d-Xylp-(1 → 4)-3,6-anhydro-l-Galp-(1 → repeat unit in the polysaccharide.

新西兰特有附生红海藻Pyrophyllon subtumens 的菌体含有高水平的木糖和大量的阿拉伯糖，但多糖尚未表征。

通过化学和光谱方法测定水溶性多糖提取物和各种衍生物中单个糖的连接/取代。

没有发现 3-连接糖，也没有发现任何d-半乳糖，这排除了在许多其他红色大型藻类中发现的琼脂、角叉菜胶或混合 3-连接/4-连接 β- d-木聚糖型多糖。相反，多糖主链主要含有4-连接的β- d-吡喃木糖基、4-连接的3，6-脱水-1-吡喃半乳糖基和4-连接的1-吡喃半乳糖基单元。每种类型的糖中的一些在不同位置被天然硫酸化。一些木糖基单元在2-或3-位被1-阿拉伯糖基单元取代。多糖很复杂，可能包含一系列结构。然而，部分测序成功地用于回收和鉴定一种新型二糖 4- O - d -xylopyranosyl-3,6-anhdydro- l -galactopyranose，这表明独特的 →4)-β- d -Xyl p -(1 → 4)-3,6-脱水-l -Gal p- (1 → 多糖中的重复单元。