Structure of chitin in the cell walls of newly formed and mature conidia of Fusarium sulphureum

1982 ◽  
Vol 28 (5) ◽  
pp. 531-535 ◽  
Author(s):  
E. F. Schneider ◽  
W. L. Seaman
Keyword(s):  
Cell Wall ◽  
Acetic Acid ◽  
Cell Walls ◽  
Molecular Hydrogen ◽  
Spectroscopic Analysis ◽  
Conidiogenous Cell ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
X Ray ◽  
Fusarium Sulphureum

Samples of 7-day-old septate conidia (mature conidia) and newly released aseptate ones (immature conidia) of Fusarium sulphureum were hydrolyzed successively in KOH, acetic acid – H2O2, and H2SO4. The cell wall residue of the mature conidia remained intact throughout the hydrolysis but that of immature conidia dissolved in the H2SO4. Thus, the immature conidial cell wall is substantially different from that of mature conidial cells or growing hyphae and the cell wall undergoes a structural transformation following conidium release from the conidiogenous cell. X-ray diffraction analyses of the wall residues following KOH and acetic acid – H2O2 hydrolysis showed that the mature conidial wall residue had a crystalline chitin component, while the residue of the immature conidial wall was more amorphous and had smaller crystals. An X-ray diffraction pattern of the dissolved immature conidial wall that was recovered from the H2SO4 hydrolysate showed that it contained crystalline chitin.Infrared spectroscopic analysis of the mature conidial cell wall residue showed absorption bands due to inter- and intra-molecular hydrogen bonding and for hydrogen stretching associated with crystalline chitin. Such bands were lacking in the immature cell wall analogue.

The effects of thermal treatment on the nanomechanical behavior of bamboo (Phyllostachys pubescens Mazel ex H. de Lehaie) cell walls observed by nanoindentation, XRD, and wet chemistry

Holzforschung ◽  
2017 ◽  
Vol 71 (2) ◽  
pp. 129-135 ◽  
Author(s):  
Yanjun Li ◽  
Chengjian Huang ◽  
Li Wang ◽  
Siqun Wang ◽  
Xinzhou Wang
Keyword(s):  
Cell Wall ◽  
Thermal Treatment ◽  
Cell Walls ◽  
Treatment Time ◽  
Lignin Content ◽  
Phyllostachys Pubescens ◽  
X Ray Diffraction ◽  
Wet Chemistry ◽  
X Ray ◽  
Wet Chemical

Abstract The effects of thermal treatment of bamboo at 130, 150, 170, and 190°C for 2, 4, and 6 h were investigated in terms of changes in chemical composition, cellulose crystallinity, and mechanical behavior of the cell-wall level by means of wet chemical analysis, X-ray diffraction (XRD), and nanoindentation (NI). Particularly, the reduced elastic modulus (Er), hardness (H), and creep behavior were in focus. Both the temperature and treatment time showed significant effects. Expectedly, the hemicelluloses were degraded and the relative lignin content was elevated, while the crystallinity of the cellulose moiety was increased upon thermal treatment. The Er and H data of the cell wall were increased after 6 h treatment at 190°C, from 18.4 to 22.0 GPa and from 0.45 to 0.65 GPa, respectively. The thermal treatment led to a decrease of the creep ratio (CIT) under the same conditions by ca. 28%. The indentation strain state (εi) also decreased significantly after thermal treatment during the load-holding stage.

Wood Petrifaction: and aspect of biomineralogy

1979 ◽  
Vol 27 (4) ◽  
pp. 377 ◽  
Author(s):  
G Scurfield
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
X Ray Diffraction ◽  
Intercellular Substance ◽  
X Ray ◽  
Colloidal Form ◽  
Cell Lumina ◽  
Mineral Deposition ◽  
Wall Components ◽  
Scanning Electron

Light microscopy, scanning electron microscopy, X-ray diffraction and differential thermal analysis have been used to examine the structure and mineralogical make-up of 79 Australian petrified woods. Initiation of petrifaction appears to rely on the provision of a substrate with inherent porosity, with the substrate components chemically rather inert and only slowly degraded at normal temperatures and pressures under conditions probably most often acid and tending to anaerobic, and the pores sufficiently large to allow access of an appropriate mineral in ionic or colloidal form in water. Stages in the process include entry of mineral solution into the wood via splits or checks, cell lumina, and other voids; permeation of cell walls; progressive dissolution of cell wall components beginning largely with lignin and accompanied by a build-up of a mineral framework adequate for maintaining the dimensional stability of the wood; mineral deposition in cell lumina after cell wall replacement as a continuous, intermittent, perhaps separate, but not obligatory event; mineral deposition in voids present or formed by dissolution of intercellular substance as a separate, but not obligatory event; and final lithification involving loss of water and perhaps replacement of one mineral by another.

Structure and composition of the cell wall of Choanephora cucurbitarum

1976 ◽  
Vol 22 (4) ◽  
pp. 486-494 ◽  
Author(s):  
D. R. Letourneau ◽  
J. M. Deven ◽  
M. S. Manocha
Keyword(s):  
Cell Wall ◽  
Cell Walls ◽  
Free Cell ◽  
Infrared Spectrophotometry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Before And After ◽  
Neutral Sugars ◽  
Choanephora Cucurbitarum ◽  
Hyphal Wall

Mechanically isolated, cytoplasm-free cell walls of Choanephora cucurbitarum were analyzed qualitatively and quantitatively by use of microchemical methods, infrared spectrophotometry, and X-ray diffraction. Chemical analysis of cell wall revealed the presence of chitin (17%), chitosan (28.4%), neutral sugars (7.2%), uronic acid (2.4%), proteins (8.2%), and lipids (13.8%). The structure of hyphal wall, investigated by electron microscopy of shadowed replicas before and after alkali-acid hydrolysis, showed two distinct regions: microfibrillar and amorphous. The microfibrils, which were composed of mainly chitin, were organized into two distinct layers; an outer, thicker layer of randomly oriented microfibrils, and an inner, thin layer of parallel microfibrils. In its structure and chemical composition the cell wall of C. cucurbitarum resembles those of other zygomycetous fungi.

scholarly journals The structure of the cell wall in some species of the filamentous green alga Cladophora

1940 ◽  
Vol 129 (854) ◽  
pp. 54-76 ◽  
Keyword(s):  
Cell Wall ◽  
Green Alga ◽  
Cell Elongation ◽  
Cell Walls ◽  
Opposite Sign ◽  
Periodic Change ◽  
X Ray Diffraction ◽  
X Ray ◽  
Filamentous Green Alga ◽  
Flat Spiral

With a view to extending the work on Valonia , the cell walls of several species of Cladophora have been examined in detail by means of X-ray diffraction photographs and the microscope. The walls are found to consist of layers in which the cellulose chains in any one layer are inclined to those in the preceding and subsequent layers at an angle whose average is less than 90°. The two sets of striations on the layers of the wall correspond closely to the directions of the cellulose chains. Each set of chains forms a spiral round the cell, and the spirals are of opposite sign. One tends to be flat and th e other steep. On the whole, th e steep spiral tends to become steeper on passing from the base of the filament to the tip, and the flat spiral flatter. In any one cell of the filament, the steep spiral is steepest at the end nearer the filament tip and the flat spiral flattest. Wherever such changes in inclination occur, the angle between the chains tends to remain constant. It is suggested that cell elongation is the factor causing the inclination of the steeper spiral to vary, and that the behaviour of the flatter spiral is best explained by the assumption of a protoplasmic mechanism causing a periodic change in the direction of cellulose chains through a constant angle. The development of a branch cell is reviewed and is found to proceed as the above suggestions would indicate.

An unusual reaction of a bridged triterpenoid α-diketone with acetic anhydride

1991 ◽  
Vol 56 (12) ◽  
pp. 2917-2935 ◽  
Author(s):  
Eva Klinotová ◽  
Václav Křeček ◽  
Jiří Klinot ◽  
Miloš Buděšínský ◽  
Jaroslav Podlaha ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Nmr Spectroscopy ◽  
Acetic Anhydride ◽  
Spectral Methods ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mild Conditions ◽  
Condensation Products ◽  
Unsaturated Lactones ◽  
C Nmr

3β-Acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) reacts with acetic anhydride in pyridine under very mild conditions affording β-lactone IVa and γ-lactones Va and VIIa as condensation products. On reaction with pyridine, lactones Va and VIIa undergo elimination of acetic acid to give unsaturated lactones VIIIa and IXa, respectively. Similarly, the condensation of 20β,28-epoxy-21,22-dioxo-18α,19βH-ursan-3β-yl acetate (IIIb) with acetic anhydride leads to β-lactone IVb and γ-lactone Vb; the latter on heating with pyridine affords unsaturated lactone VIIIb and 21-methylene-22-ketone Xb. The structure of the obtained compounds was derived using spectral methods, particularly 1H and 13C NMR spectroscopy; structure of lactone IVa was confirmed by X-ray diffraction.

scholarly journals Tautomerisation in 1-(4-Methylphenylazo)naphthalen-2-ol and 2-(4-Methylphenylazo)-4-methylphenol: A Crystallographic and 13C{1H}NMR Study

1999 ◽  
Vol 23 (3) ◽  
pp. 178-179
Author(s):  
Wendy I. Cross ◽  
Kevin R. Flower ◽  
Robin G. Pritchard
Keyword(s):  
Acetic Acid ◽  
Nmr Spectroscopy ◽  
Resonant Frequency ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Nmr Study ◽  
Acetic Acid Esters ◽  
Acid Esters ◽  
Equivalent Carbon

The acetic acid esters of 1-(4-methylphenylazo)naphthalen-2-ol 1 and 2-(4-methylphenylazo)-4-methylphenol 3 are prepared and characterised by single crystal X-ray diffraction studies and 13C{1H}NMR spectroscopy; the position of the C(2)13C resonance for the ester is used to predict the position of resonant frequency of the equivalent carbon in the parent alcohols and hence, calculate the position of the azo-hydrazone equilibrium in these compounds.

Preparation and Characterization of Polyaniline Nanotubes Doped with Different Acid

2013 ◽  
Vol 401-403 ◽  
pp. 663-666
Author(s):  
Xue Lian Bai ◽  
Jian Ting Mei ◽  
Zhong Guo Mu ◽  
Yun Bai
Keyword(s):  
Acetic Acid ◽  
Self Assembly ◽  
Ammonium Persulfate ◽  
Tetraacetic Acid ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure And Property ◽  
Assembly Method ◽  
Polyaniline Nanotubes

Polyaniline (PANI) nanotubes were synthesized separately using amino acetic acid (AA), ethylenediamine tetraacetic acid (EDTA), oxalic acid (OA) as dopant and ammonium persulfate (APS) as oxidant by a self-assembly method. SEM, TEM,FTIR and X-ray diffraction (XRD) and applying the 4 probes method characterized the morphology, structure and property of the product. It was found that nanotubes morphology were synthesized when the [Aci/[A ratio is 1:2.The room template conductivity of the products were studied.

Metal Phenoxyalkanoic Acid Interactions. XXV. The Crystal Structures of (2-Formyl-6-Methoxyphenoxy)Acetic Acid and Its Zinc(II) Complex and the Lithium, Zinc(II) and Cadmium(II) Complexes of (2-Chlorophenoxy)Acetic Acid

1987 ◽  
Vol 40 (7) ◽  
pp. 1147 ◽  
Author(s):  
EJ Oreilly ◽  
G Smith ◽  
CHL Kennard ◽  
TCW Mak
Keyword(s):  
Acetic Acid ◽  
Crystal Structures ◽  
Free Acid ◽  
Rotational Symmetry ◽  
Carboxyl Groups ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Third ◽  
Planar Complex ◽  
Hydrogen Bonded

The crystal structures of (2-formyl-6-methoxyphenoxy)acetic acid (1), diaquabis [(2-formyl-6-methoxyphenoxy) acetato ]zinc(11) (2), tetraaquabis [(2-chlorophenoxy) acetato ]zinc(11) (3), triaquabis [(2-chlorophenoxy) acetato ]cadmium(11) dihydrate (4) and lithium (2-chloro- phenoxy )acetate 1.5 hydrate (5) have been determined by X-ray diffraction. The acid (1) forms centrosymmetric hydrogen-bonded cyclic dimers [O…0, 2.677(6) �] which are non-planar. Complex (2) is six-coordinate with two waters [Zn- Ow , 1.997(2) �] and four oxygens from two asymmetric bidentate carboxyl groups [Zn-O, 2.073, 2.381(2) �] completing a skew trapezoidal bipyramidal stereochemistry. Complex (5) is also six-coordinate but is octahedral, with two trans-related unidentate carboxyl oxygens [mean Zn-O, 2.134(9) �] and four waters [mean Zn-O, 2.081(9) �]. The seven-coordinate complex (4) has crystallographic twofold rotational symmetry relating two :symmetric bidentate acid ligands [ Cd -O, 2.26, 2 48(:) �] and two waters [ Cd -O, 2.34(2) �] while the third water lies on this axis [ Cd -O, 2.27(2) �]. In contrast to the monomers (2)-(4), complex (5) is polymeric with tetrahedral lithium coordinated to one water and three carboxylate oxygens [mean Li-0, 1.95(1) �]. The essential conformation of the free acid is retained in complexes (2), (3) and (4) but in (5), it is considerably changed.

Synthesis of Galactomannan Sulfate-Citrate

2022 ◽  
Vol 1049 ◽  
pp. 218-223
Author(s):  
Aleksandr S. Kazachenko ◽  
Yuriy N. Malyar ◽  
Anna S. Kazachenko
Keyword(s):  
Biological Activity ◽  
Ftir Spectroscopy ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
X Ray ◽  
Mixed Ester ◽  
First Time ◽  
Derivatives Of

Sulfated derivatives of polysaccharides have anticoagulant, hypolipedimic and other biological activity. In this work, a complex mixed ester of galactomannan, its sulfate-citrate, was obtained for the first time. The introduction of citrate and sulfate groups was proved by FTIR spectroscopy by the appearance of corresponding absorption bands. It was shown by X-ray diffraction that the introduction of the citrate group leads to the amorphization of the galactomannan structure.

Improved Enzymatic Depolymerization of Chitosan by Ionic Liquid Pretreatment and the Effect of Oligo-Chitosan on Intestinal Flora In Vitro

2011 ◽  
Vol 391-392 ◽  
pp. 1319-1323
Author(s):  
Cui Zheng ◽  
Lin Li ◽  
Hao Pang ◽  
Zhao Mei Wang ◽  
Na Li
Keyword(s):  
Ionic Liquid ◽  
Hydrogen Bonds ◽  
Molecular Hydrogen ◽  
Intestinal Flora ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrolysis Of ◽  
Positive Effect ◽  
Enzymatic Depolymerization

It still remains challenging for effective hydrolysis of chitosan into chitosan oligomers. In this work, a pretreatment was conducted on chitosan by an ionic liquid 1-butyl-3-methylimidazolium chloride ([C4mim]Cl), aiming at improving enzymatic depolymerization of chitosan. X-ray diffraction analysis indicated that the inter- and intra-molecular hydrogen bonds within chitosan molecules were broken by [C4mim]Cl and the crystalline was destroyed. The oligo-chitosan hydrolyzed from IL-pretreated chitosan, coded as COS-IL, showed a DP of 3~5, in contrast to DP 5~8 with oligo-chitosan obtained from untreated chitosan(coded as COS-UN). COS-IL was more effective than COS-UN in inhibiting intestinal spoilage bacterials growth and it has positive effect on the growth of intestinal probiotic bacterials.

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