Effect of soybean processing on cell wall porosity and protein digestibility

Abstract Efficient convention of bamboo biomass into biofuel and biomaterials, as well as chemical treatment are both highly related to the porosity of cell wall. The present work characterizes the micropore and mesopore structure in cell walls of six different bamboo species and tissue types using CO2 and N2 adsorption. Two plantation wood species were also tested for comparison. Bamboo species normally showed lower cell wall porosity (2.64%-3.75%) than wood species (3.98%-5.06%), indicating a more compact structure for bamboo than wood. A distinct species dependence of cell wall pore structures and porosity was also observed. Furthermore, the cell wall pore structure and porosity are shown to be tissue-specific, as the parenchyma cells exhibit higher pore volume and porosity compared to bamboo fibers. The obtained results give new explanations on the known facts that both bamboo and bamboo fibers exhibit higher biomass recalcitrance as compared to wood and bamboo parenchyma cells, constructing the base of pretreatment optimization and subsequent processing for bamboo-derived biofuels and biomaterials.

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Food for Thought: Enzyme Action

Reactions ◽

10.1093/oso/9780199695126.003.0034 ◽

2011 ◽

Author(s):

Peter Atkins

Keyword(s):

Cell Wall ◽

Specific Enzyme ◽

Complex Molecules ◽

Enzyme Action ◽

Target Molecule ◽

Fatal Bleeding ◽

To Come ◽

Enzyme Molecules ◽

Essential Contribution ◽

Chymotrypsin A

Nature makes use of the tools that I have been developing, and does so in the most extraordinary and subtle manner. After all, she has had about four billion years to come up with solutions to problems with which human chemists have striven seriously for only a century or so. Most of the reactions that go on in organisms—including you—are controlled by the proteins called ‘enzymes’ (a name derived from the Greek words for ‘in leaven’, as in yeast). Enzymes are biological catalysts (Reaction 11) that are extraordinarily specific and highly effective in their role. One of these complex molecules might serve as the merest foot soldier in the army of reactions going on inside you, with a role such as severing the bond between two specific groups of atoms in a target molecule. Because their function may be highly specific, enzyme molecules need to be large: they have to recognize the molecule they act on, act on it, then release it so that they can act again. Thus, they have to have several functions built into them. As you will see, enzymes are the ultimate in functional blindness: they feel around in their surroundings in order to identify their substrate, the species they can act on. Life is ultimately blind chemical progress guided by touch. I am going to introduce you to one particular group of enzymes, the ‘proteases’, and focus on one example from this group, namely chymotrypsin. A protease is a traitor to its kind: it is a protein that breaks down other proteins. It plays a role in digestion, of course, but its range is much wider. One protease enables a lucky sperm to eat through the cell wall of an egg and ensure its at least temporary immortality. Another facilitates the clotting of blood to terminate possibly fatal bleeding. Chymotrypsin itself is an enzyme that is secreted from the pancreas into the intestine, and makes an essential contribution to the process of digestion. Its name is derived slightly circuitously from the Greek words for animal fluid, a bodily ‘humour’, and rubbing, as it was obtained as a fluid by rubbing the pancreas.

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Novel tool to quantify cell wall porosity relates wall structure to cell growth and drug uptake

The Journal of Cell Biology ◽

10.1083/jcb.201810121 ◽

2019 ◽

Vol 218 (4) ◽

pp. 1408-1421 ◽

Cited By ~ 5

Author(s):

Xiaohui Liu ◽

Jiazhou Li ◽

Heyu Zhao ◽

Boyang Liu ◽

Thomas Günther-Pomorski ◽

...

Keyword(s):

Cell Wall ◽

Cell Walls ◽

Dynamic Structure ◽

Cell Types ◽

Antifungal Drugs ◽

Drug Uptake ◽

Wall Structure ◽

Quenching Efficiency ◽

Model Plant Arabidopsis Thaliana ◽

Cell Wall Porosity

Even though cell walls have essential functions for bacteria, fungi, and plants, tools to investigate their dynamic structure in living cells have been missing. Here, it is shown that changes in the intensity of the plasma membrane dye FM4-64 in response to extracellular quenchers depend on the nano-scale porosity of cell walls. The correlation of quenching efficiency and cell wall porosity is supported by tests on various cell types, application of differently sized quenchers, and comparison of results with confocal, electron, and atomic force microscopy images. The quenching assay was used to investigate how changes in cell wall porosity affect the capability for extension growth in the model plant Arabidopsis thaliana. Results suggest that increased porosity is not a precondition but a result of cell extension, thereby providing new insight on the mechanism plant organ growth. Furthermore, it was shown that higher cell wall porosity can facilitate the action of antifungal drugs in Saccharomyces cerevisiae, presumably by facilitating uptake.

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Resistance of thermally modified and pressurized hot water extracted Scots pine sapwood against decay by the brown-rot fungus Rhodonia placenta

European Journal of Wood and Wood Products ◽

10.1007/s00107-019-01482-z ◽

2019 ◽

Vol 78 (1) ◽

pp. 161-171 ◽

Cited By ~ 5

Author(s):

Michael Altgen ◽

Suvi Kyyrö ◽

Olli Paajanen ◽

Lauri Rautkari

Keyword(s):

Cell Wall ◽

Mass Loss ◽

Scots Pine ◽

Elevated Temperatures ◽

Brown Rot ◽

Decay Resistance ◽

Hot Water ◽

Decay Fungi ◽

Effective Reduction ◽

Cell Wall Porosity

AbstractThe thermal degradation of wood is affected by a number of process parameters, which may also cause variations in the resistance against decay fungi. This study compares changes in the chemical composition, water-related properties and decay resistance of Scots pine sapwood that was either thermally modified (TM) in dry state at elevated temperatures (≥ 185 °C) or treated in pressurized hot water at mild temperatures (≤ 170 °C). The thermal decomposition of easily degradable hemicelluloses reduced the mass loss caused by Rhodonia placenta, and it was suggested that the cumulative mass loss is a better indicator of an actual decay inhibition. Pressurized hot water extraction (HWE) did not improve the decay resistance to the same extent as TM, which was assigned to differences in the wood-water interactions. Cross-linking reactions during TM caused a swelling restraint and an effective reduction in moisture content. This decreased the water-swollen cell wall porosity, which presumably hindered the transport of degradation agents through the cell wall and/or reduced the accessibility of wood constituents for degradation agents. This effect was absent in hot water-extracted wood and strong decay occurred even when most hemicelluloses were already removed during HWE.

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Deletion analysis and localization of SbPRP1, a soybean cell wall protein gene, in roots of transgenic tobacco and cowpea1

Plant Molecular Biology ◽

10.1007/bf00039622 ◽

1993 ◽

Vol 21 (1) ◽

pp. 109-119 ◽

Cited By ~ 18

Author(s):

H. Suzuki ◽

T. J. Fowler ◽

M. L. Tierney

Keyword(s):

Cell Wall ◽

Transgenic Tobacco ◽

Protein Gene ◽

Cell Wall Protein ◽

Deletion Analysis ◽

Soybean Cell

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Stability of tryptophan during food processing and storage

British Journal Of Nutrition ◽

10.1079/bjn19850035 ◽

1985 ◽

Vol 53 (2) ◽

pp. 281-292 ◽

Cited By ~ 35

Author(s):

Henrik K. Nielsen ◽

D. De Weck ◽

P. A. Finot ◽

R. Liardon ◽

R. F. Hurrell

Keyword(s):

Food Processing ◽

Whey Proteins ◽

Milk Powder ◽

Protein Digestibility ◽

Model Systems ◽

Maillard Reactions ◽

Minor Losses ◽

Oxidation Of Methionine ◽

Processing And Storage ◽

And Storage

1. The stability of tryptophan was evaluated in several different food model systems using a chemical method (high pressure liquid chromatography after alkaline-hydrolysis) and rat assays. Losses of tryptophan were compared with the losses of lysine and methionine.2. Whey proteins stored in the presence of oxidizing lipids showed large losses of lysine and extensive methionine oxidation but only minor losses of tryptophan as measured chemically. The observed decrease in bioavailable tryptophan was explained by a lower protein digestibility.3. Casein treated with hydrogen peroxide to oxidize all methionine to methionine sulphoxide showed a 9% loss in bioavailable tryptophan.4. When casein was reacted with caffeic acid at pH 7 in the presence of monophenol monooxygenase (tyrosinase; EC 1.14.18.l), no chemical loss of tryptophan occurred, although fluorodinitrobenzene-reactive lysine fell by 23%. Tryptophan bioavailability fell IS%, partly due to an 8% reduction in protein digestibility.5. Alkali-treated casein (0.15 M-sodium hydroxide, 80°,4 h) did not support rat growth. Chemically-determined tryptophan, available tryptophan and true nitrogen digestibility fell 10, 46 and 23% respectively. Racemization of tryptophan was found to be 10% (D/(D+L)).6. In whole-milk powder, which had undergone ‘early’ or ‘advanced’ Maillard reactions, tryptophan, determined chemically or in rat assays, was virtually unchanged. Extensive lysine losses occurred.7. It was concluded that losses of tryptophan during food processing and storage are small and of only minor nutritional importance, especially when compared with much larger losses of lysine and the more extensive oxidation of methionine.

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The glucanase-soluble mannoproteins limit cell wall porosity inSaccharomyces cerevisiae

Yeast ◽

10.1002/yea.320060606 ◽

1990 ◽

Vol 6 (6) ◽

pp. 491-499 ◽

Cited By ~ 175

Author(s):

Johannes G. De Nobel ◽

Frans M. Klis ◽

Jan Priem ◽

Teun Munnik ◽

Herman Van Den Ende

Keyword(s):

Cell Wall ◽

Cell Wall Porosity

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Effects of induced, subclinical phosphorus deficiency on feed intake and growth of beef heifers

The Journal of Agricultural Science ◽

10.1017/s002185960004106x ◽

1982 ◽

Vol 98 (1) ◽

pp. 23-29 ◽

Cited By ~ 23

Author(s):

B. J. W. Gartner ◽

G. M. Murphy ◽

W. A. Hoey

Keyword(s):

Cell Wall ◽

Weight Gain ◽

Feed Intake ◽

Crude Protein ◽

Phosphorus Deficiency ◽

Protein Digestibility ◽

Inorganic Phosphorus ◽

Feed Conversion ◽

Beef Heifers ◽

Low Phosphorus

SUMMARYHereford heifers were fed a diet (7·0 MJ ME/kg D.M.) containing 0·09 % phosphorus but complete with regard to other nutrient constituents. Only after 19 weeks wore the effects of subclinical aphosphorosis evident in the form of reduction in feed intake, cessation of weight gain, increased feed conversion and decreases in tho concentration of inorganic phosphorus in blood and saliva. Heifers supplemented daily with 12 g phosphorus sustained a weight gain of about 0–2 kg/day over 62 weeks as did other supplemented heifers whose feed intake was restricted to that of tho low phosphorus treatment. The effects of phosphorus supplementation were thus demonstrated without being confounded by concomitant increases in feed intake.Phosphorus supplementation resulted in significantly lowered apparent crude protein digestibility and a slight increaso in cell wall digestibility.

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