Does harvesting age matter? Changes in structure and rheology of a shear-thickening polysaccharide from Cyathea medullaris as a function of age

被引：2

作者：

Bisht, Akshay ^{[1
]}

Goh, Kelvin K. T. ^{[1
]}

Sims, Ian M. ^{[2
]}

Edwards, Patrick J. B. ^{[3
]}

Matia-Merino, Lara ^{[1
]}

机构：

[1] Massey Univ, Sch Food & Adv Technol, Palmerston North, New Zealand

[2] Victoria Univ Wellington, Ferrier Res Inst, Wellington, New Zealand

[3] Massey Univ, Sch Nat Sci, Palmerston North, New Zealand

来源：

CARBOHYDRATE POLYMERS | 2024年 / 329卷

关键词：

Mamaku polysaccharide; Shear-thickening; Molecular structure; Shear rheology; Extensional rheology; BLACK TREE FERN; EXTENSIONAL RHEOLOGY; NONLINEAR SHEAR; AQUEOUS-SOLUTIONS; MOLECULAR-WEIGHT; GUM EXUDATE; CELL-WALL; VISCOSITY; BEHAVIOR; FILAMENT;

D O I：

10.1016/j.carbpol.2023.121757

中图分类号：

O69 [应用化学];

学科分类号：

081704 ;

摘要：

A shear-thickening polysaccharide from the New Zealand Black tree fern (Cyathea medullaris, commonly known as mamaku) extracted from different age fronds (stage 1: young, stage 2: fully grown and stage 3: old) was characterised in terms of structure and rheological properties. Constituent sugar analysis and H-1 and C-13 NMR revealed a repeating backbone of -4)-beta-D-GlcpA-(1 -> 2)-alpha-D-Manp-(1 ->, for all mamaku polysaccharide (MP) samples from different age fronds without any alterations in molecular structure. However, the molecular weight (M-w) was reduced with increasing age, from similar to 4.1 x 10(6) to similar to 2.1 x 10(6) Da from stage 1 to stage 3, respectively. This decrease in M-w (and size) consequently reduced the shear viscosity (eta(s-Stage 1) > eta(s-Stage 2) > eta(s-Stage 3)). However, the extent of shear-thickening and uniaxial extensional viscosity of MP stage 2 was greater than MP stage 1, which was attributed to a greater intermolecular interaction occurring in the former. Shear-thickening behaviour was not observed in MP stage 3.

引用

页数：12

共 66 条

[1] Chemical composition and molecular structure of polysaccharide-protein biopolymer from Durio zibethinus seed: extraction and purification process [J].