Chemical Structure, Molecular Size Distributions, and Rheological Properties of Flaxseed Gum

Humic substances (HS) are dominant components of soil organic matter and are recognized as natural, effective growth promoters to be used in sustainable agriculture. In recent years, many efforts have been made to get insights on the relationship between HS chemical structure and their biological activity in plants using combinatory approaches. Relevant results highlight the existence of key functional groups in HS that might trigger positive local and systemic physiological responses via a complex network of hormone-like signaling pathways. The biological activity of HS finely relies on their dosage, origin, molecular size, degree of hydrophobicity and aromaticity, and spatial distribution of hydrophilic and hydrophobic domains. The molecular size of HS also impacts their mode of action in plants, as low molecular size HS can enter the root cells and directly elicit intracellular signals, while high molecular size HS bind to external cell receptors to induce molecular responses. Main targets of HS in plants are nutrient transporters, plasma membrane H+-ATPases, hormone routes, genes/enzymes involved in nitrogen assimilation, cell division, and development. This review aims to give a detailed survey of the mechanisms associated to the growth regulatory functions of HS in view of their use in sustainable technologies.

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Influence of unadsorbed emulsifiers on the rheological properties and structure of heteroaggregate of whey protein isolate (WPI) coated droplets and flaxseed gum (FG) coated droplets

Food Hydrocolloids ◽

10.1016/j.foodhyd.2018.01.041 ◽

2018 ◽

Vol 80 ◽

pp. 42-52 ◽

Cited By ~ 10

Author(s):

Xu Wang ◽

Xin Li ◽

Duoxia Xu ◽

Guorong Liu ◽

Junsong Xiao ◽

...

Keyword(s):

Rheological Properties ◽

Whey Protein ◽

Whey Protein Isolate ◽

Protein Isolate ◽

Flaxseed Gum

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Understanding the influence of chemical structure and length of hydrophobic blocks on the rheological properties of associative copolymers

European Polymer Journal ◽

10.1016/j.eurpolymj.2020.110190 ◽

2021 ◽

Vol 143 ◽

pp. 110190

Author(s):

Claude St Thomas ◽

Luis Ernesto Elizalde ◽

Enrique Jiménez Regalado ◽

Marco A. De Jesús-Téllez ◽

Grit Festag ◽

...

Keyword(s):

Rheological Properties ◽

Chemical Structure

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Analysis of Structural and Functional Differences of Glucans Produced by the Natively Released Dextransucrase of Liquorilactobacillus hordei TMW 1.1822

Applied Biochemistry and Biotechnology ◽

10.1007/s12010-020-03407-6 ◽

2020 ◽

Vol 193 (1) ◽

pp. 96-110 ◽

Cited By ~ 1

Author(s):

Jonas Schmid ◽

Daniel Wefers ◽

Rudi F. Vogel ◽

Frank Jakob

Keyword(s):

Molecular Weight ◽

Secondary Structure ◽

Rheological Properties ◽

Viscoelastic Fluid ◽

Size Structure ◽

Molecular Size ◽

Molecular Structures ◽

Rheological Measurements ◽

Functional Differences ◽

Functionally Diverse

AbstractThe properties of the glucopolymer dextran are versatile and linked to its molecular size, structure, branching, and secondary structure. However, suited strategies to control and exploit the variable structures of dextrans are scarce. The aim of this study was to delineate structural and functional differences of dextrans, which were produced in buffers at different conditions using the native dextransucrase released by Liquorilactobacillus (L.) hordei TMW 1.1822. Rheological measurements revealed that dextran produced at pH 4.0 (MW = 1.1 * 108 Da) exhibited the properties of a viscoelastic fluid up to concentrations of 10% (w/v). By contrast, dextran produced at pH 5.5 (MW = 1.86 * 108 Da) was gel-forming already at 7.5% (w/v). As both dextrans exhibited comparable molecular structures, the molecular weight primarily influenced their rheological properties. The addition of maltose to the production assays caused the formation of the trisaccharide panose instead of dextran. Moreover, pre-cultures of L. hordei TMW 1.1822 grown without sucrose were substantial for recovery of higher dextran yields, since the cells stored the constitutively expressed dextransucrase intracellularly, until sucrose became available. These findings can be exploited for the controlled recovery of functionally diverse dextrans and oligosaccharides by the use of one dextransucrase type.

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