scholarly journals A method to measure the water-holding properties of dietary fibre using suction pressure

1981 ◽  
Vol 46 (2) ◽  
pp. 247-255 ◽  
Author(s):  
J. A. Robertson ◽  
M. A. Eastwood
Keyword(s):  
Dietary Fibre ◽  
Gum Arabic ◽  
Water Soluble ◽  
Suction Pressure ◽  
Physiological Conditions ◽  
Fibre Concentration ◽  
Vegetable Fibre ◽  
Water Holding ◽  
Fibre Matrix

1. Water-holding capacity (WHC) of dietary fibre is usually considered as the amount of water held but the manner in which water is held by the fibre matrix may be more relevant in understanding the role of fibre in nutrition.2. A method used to determine WHC under physiological conditions has been adapted to determine how strongly water is held by fibre. Solutions of compounds, such as polyethylene glycol, of known osmotic potential are used to generate a suction pressure across a dialysis membrane containing a fibre sample. The WHC at each suction pressure can then be determined.3. The method can be applied to water-soluble and water-insoluble sources of fibre. Fibre sources studied included potato fibre concentrate, bran and gum arabic.4. Results are comparable to other similar systems of WHC measurement for gels and suggest that vegetable fibre has water-holding properties more akin to a true gel than bran. Bran has very poor water-holding properties.5. Differences in WHC between fibre sources are more apparent if WHC is considered as fibre concentration (g fibre/g water).6. Differences in the water-holding properties could be important in determining fibre activity in the gut.

Relationship between water holding capacity and fibre concentration in equine feeds

2004 ◽  
Vol 32 ◽  
pp. 233-237
Author(s):  
J J Hyslop ◽  
B M L McLean ◽  
M J S Moore-Colyer
Keyword(s):  
Cell Wall ◽  
Water Content ◽  
Functional Properties ◽  
Nutritive Value ◽  
Daily Basis ◽  
Water Holding Capacity ◽  
Fibre Concentration ◽  
Water Holding ◽  
Fibre Matrix

The water content of feedstuffs is an important factor when considering both the nutritive value of a feed for dietary rationing purposes and when assessing the functional properties associated with the practical inclusion of a feedstuff in animal diets. Water is a vital nutrient in its own right and must be supplied on a daily basis. Feed associated water provides one source of this obligatory requirement. In addition, the water holding capacity (WHC) of a feedstuff and its relationship with other constituents of the feed may have important effects. Water can be associated with feedstuff in one of three ways (Robertson and Eastwood, 1981b). Firstly, water can be bound by the hydrophilic polysaccharides of the fibre component of feeds. Secondly, water can be held within the structural fibre matrix of feeds and finally, water can be associated with feedstuff fibre other than bound or matrix water and is usually considered as water trapped within the cell wall lumen.

scholarly journals An examination of factors which may affect the water holding capacity of dietary fibre

1981 ◽  
Vol 45 (1) ◽  
pp. 83-88 ◽  
Author(s):  
J. A. Robertson ◽  
M. A. Eastwood
Keyword(s):  
Chemical Composition ◽  
Dietary Fibre ◽  
Bound Water ◽  
Water Holding Capacity ◽  
Distinct Structure ◽  
Vegetable Fibre ◽  
Acid Detergent Fibre ◽  
Method Of Measurement ◽  
Water Holding ◽  
Fibre Preparation

1. Dietary fibre has a water holding capacity (WHC) and this is a function of the fibre source and method of measurement. Water can be associated with fibre either as trapped water or bound water. This makes it difficult to predict the ability of fibre to influence stool weight in humans.2. Examination of various fibre concentrates for chemical composition, as neutral detergent fibre (NDF), acid detergent fibre (ADF) and lignin; structure, by scanning electron microscopy; WHC, by centrifugation, suggests that WHC is more a function of fibre structure than chemical composition. Cereal fibre and vegetable fibre have a different chemical composition and are structurally very distinct. Structure is also dependent on the method of fibre preparation.3. Measurement of WHC by centrifugation gives an estimate of the water which can be bound and also trapped by the fibre. The amount of trapped water will depend on the structure of the fibre whereas bound water will depend on the chemical composition.

scholarly journals Measurement of water-holding properties of fibre and their faecal bulking ability in man

1983 ◽  
Vol 50 (3) ◽  
pp. 539-547 ◽  
Author(s):  
M. A. Eastwood ◽  
J. A. Robertson ◽  
W. G. Brydon ◽  
Dorothy MacDonald
Keyword(s):  
Flow Rate ◽  
Water Flow Rate ◽  
Gum Arabic ◽  
Dietary Supplementation ◽  
Suction Pressure ◽  
Stool Weight ◽  
In Vitro Methods ◽  
Cereal Bran ◽  
Water Holding

1. Experiments to measure the effect of a fibre source in the diet on stool bulk are difficult and lack precision. In vitro methods which would identify fibre sources that are effective for clinical and epidemiologic use would be valuable. One important property of fibre which influences the ability of fibre to increase stool weight is its water-holding capacity (WHC).2. WHC was measured using centrifugation, filtration, suction pressure and water flow-rate techniques using fibre concentrates of potato, cereal bran and gum arabic.3. Dietary supplementation of three preparations of potato fibre (20 g/d) had no significant effect on stool weight but 16 g bran/d increased stool weight from 107 (SE 44) g/d to 174 (SE 51) g/d.4. The effects of these fibres on stool weight can be related to the nature of the water-holding properties of fibre rather than absolute WHC.

Molecular, rheological and physicochemical characterisation of puka gum, an arabinogalactan-protein extracted from the Meryta sinclairii tree

2020 ◽  
Author(s):  
MSM Wee ◽  
Ian Sims ◽  
KKT Goh ◽  
L Matia-Merino
Keyword(s):  
Hydrodynamic Radius ◽  
Average Molecular Weight ◽  
Gum Arabic ◽  
Water Soluble ◽  
Arabinogalactan Protein ◽  
Type Ii ◽  
Weight Average Molecular Weight ◽  
Soluble Polysaccharide ◽  
Physicochemical Characterisation ◽  
Increasing Temperature

© 2019 Elsevier Ltd A water-soluble polysaccharide (type II arabinogalactan-protein) extracted from the gum exudate of the native New Zealand puka tree (Meryta sinclairii), was characterised for its molecular, rheological and physicochemical properties. In 0.1 M NaCl, the weight average molecular weight (Mw) of puka gum is 5.9 × 106 Da with an RMS radius of 56 nm and z-average hydrodynamic radius of 79 nm. The intrinsic viscosity of the polysaccharide is 57 ml/g with a coil overlap concentration 15% w/w. Together, the shape factor, p, of 0.70 (exponent of RMS radius vs. hydrodynamic radius), Smidsrød-Haug's stiffness parameter B of 0.031 and Mark-Houwink exponent α of 0.375 indicate that the polysaccharide adopts a spherical conformation in solution, similar to gum arabic. The pKa is 1.8. The polysaccharide exhibits a Newtonian to shear-thinning behaviour from 0.2 to 25% w/w. Viscosity of the polysaccharide (1 s−1) decreases with decreasing concentration, increasing temperature, ionic strength, and at acidic pH.

Involvement of Heme Oxygenase-1 in Neuropsychiatric and Neurodegenerative Diseases

2018 ◽  
Vol 24 (20) ◽  
pp. 2283-2302 ◽  
Author(s):  
Vivian B. Neis ◽  
Priscila B. Rosa ◽  
Morgana Moretti ◽  
Ana Lucia S. Rodrigues
Keyword(s):  
Neurodegenerative Diseases ◽  
Heme Oxygenase ◽  
Therapeutic Potential ◽  
Redox Homeostasis ◽  
Antioxidant Defenses ◽  
Heme Oxygenase 1 ◽  
Physiological Conditions ◽  
And Oxidative Stress ◽  
Defensive Mechanism

Heme oxygenase (HO) family catalyzes the conversion of heme into free iron, carbon monoxide and biliverdin. It possesses two well-characterized isoforms: HO-1 and HO-2. Under brain physiological conditions, the expression of HO-2 is constitutive, abundant and ubiquitous, whereas HO-1 mRNA and protein are restricted to small populations of neurons and neuroglia. HO-1 is an inducible enzyme that has been shown to participate as an essential defensive mechanism for neurons exposed to oxidant challenges, being related to antioxidant defenses in certain neuropathological conditions. Considering that neurodegenerative diseases (Alzheimer’s Disease (AD), Parkinson’s Disease (PD) and Multiple Sclerosis (MS)) and neuropsychiatric disorders (depression, anxiety, Bipolar Disorder (BD) and schizophrenia) are associated with increased inflammatory markers, impaired redox homeostasis and oxidative stress, conditions that may be associated with alterations in HO-levels/activity, the purpose of this review is to present evidence on the possible role of HO-1 in these Central Nervous System (CNS) diseases. In addition, the possible therapeutic potential of targeting brain HO-1 is explored in this review.

Pathophysiology of Thrombosis in Peripheral Artery Disease

2020 ◽  
Vol 18 (3) ◽  
pp. 204-214 ◽  
Author(s):  
Aida Habib ◽  
Giovanna Petrucci ◽  
Bianca Rocca
Keyword(s):  
Vascular Tone ◽  
Platelet Reactivity ◽  
Coagulation Factors ◽  
Peripheral Artery ◽  
Antithrombotic Agents ◽  
Pharmacological Interventions ◽  
Physiological Conditions ◽  
Vasoactive Mediators ◽  
Artery Disease

<P>Under physiological conditions, peripheral arteries release endogenous vascular-protective and antithrombotic agents. Endothelial cells actively synthesize vasoactive mediators, which regulate vascular tone and platelet reactivity thus preventing thrombosis. Atherosclerosis disrupts homeostasis and favours thrombosis by triggering pro-thrombotic responses in the vessels, platelet activation, aggregation as well as vasoconstriction, phenomena that ultimately lead to symptomatic lumen restriction or complete occlusion. <P> In the present review, we will discuss the homeostatic role of arterial vessels in releasing vascular-protective agents, such as nitric oxide and prostacyclin, the role of pro- and anti-thrombotic vascular receptors as well as the contribution of circulating platelets and coagulation factors in triggering the pro-thrombotic response(s). We will discuss the pathological consequences of disrupting the protective pathways in the arteries and the pharmacological interventions along these pathways.</P>

scholarly journals Spent Brewer’s Yeast as a Source of Insoluble β-Glucans

2021 ◽  
Vol 22 (2) ◽  
pp. 825
Author(s):  
Ionut Avramia ◽  
Sonia Amariei
Keyword(s):  
Emulsion Stability ◽  
Extraction Process ◽  
Brewer’S Yeast ◽  
Brewer's Yeast ◽  
Brewing Process ◽  
Food Applications ◽  
Water Holding ◽  
Potential Food ◽  
Insight Into

In the brewing process, the consumption of resources and the amount of waste generated are high and due to a lot of organic compounds in waste-water, the capacity of natural regeneration of the environment is exceeded. Residual yeast, the second by-product of brewing is considered to have an important chemical composition. An approach with nutritional potential refers to the extraction of bioactive compounds from the yeast cell wall, such as β-glucans. Concerning the potential food applications with better textural characteristics, spent brewer’s yeast glucan has high emulsion stability and water-holding capacity fitting best as a fat replacer in different food matrices. Few studies demonstrate the importance and nutritional role of β-glucans from brewer’s yeast, and even less for spent brewer’s yeast, due to additional steps in the extraction process. This review focuses on describing the process of obtaining insoluble β-glucans (particulate) from spent brewer’s yeast and provides an insight into how a by-product from brewing can be converted to potential food applications.

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