Biological and chemical characteristics of "included sapwood" of Juniperus virginiana L.

Holzforschung ◽  
2004 ◽  
Vol 58 (1) ◽  
pp. 74-81 ◽  
Author(s):  
J. Bauch ◽  
J. Puls ◽  
R. Klupsch ◽  
C. Vogel
Keyword(s):  
Spectroscopic Analysis ◽  
Histological Study ◽  
Physiological Activity ◽  
Brown Rot ◽  
Chemical Characteristics ◽  
Juniperus Virginiana ◽  
Chemical Analyses ◽  
Brown Rot Fungus ◽  
Definition Of ◽  
Petrol Ether

Abstract The reddish-violet heartwood of Juniperus virginiana L. contains irregularly distributed and longitudinally oriented streaks of light-coloured wood, described as “included sapwood”. A histological study revealed that a blockage of the rays, which is caused by wounds often associated with tiny shakes, branch stubs and included bark, may lead to this anomaly. A study of fresh wood immediately after felling of the trees showed that “included sapwood” lacks physiological activity similar to the adjacent normal heartwood. Cellular UV-spectroscopic analysis revealed a secondary metabolism particularly of phenolic compounds in the pit membranes of tracheids during “included sapwood” formation, whereas the reddish-violet flavonoid compounds do not develop in this anomalous wood. Chemical analyses of petrol ether, diethyl ether, acetone and ethanol/water extracts of sapwood, “included sapwood” and heartwood showed that the accessory compounds cedrol, α-cedrene, widdrol, thujopsene and cuparene increased in “included sapwood” compared to sapwood. As opposed to the reddish-violet heartwood compounds, these sesquiterpenes turned out to be highly toxic against a brown-rot fungus in a bioassay. These findings justify defining “included sapwood” as a heartwood anomaly, since the important wood characteristics of this tissue obey the definition of heartwood rather than sapwood. This anomaly should no longer be a reason to exclude this type of wood from commercial utilisation.

Effect of biodegradation on thermogravimetric and chemical characteristics of hardwood and softwood by brown-rot fungus

2016 ◽  
Vol 211 ◽  
pp. 443-450 ◽  
Author(s):  
Zhenzhong Gao ◽  
Qi Fan ◽  
Zesen He ◽  
Zhinan Wang ◽  
Xiaobo Wang ◽  
...  
Keyword(s):  
Brown Rot ◽  
Chemical Characteristics ◽  
Brown Rot Fungus

scholarly journals A Lytic Polysaccharide Monooxygenase with Broad Xyloglucan Specificity from the Brown-Rot Fungus Gloeophyllum trabeum and Its Action on Cellulose-Xyloglucan Complexes

2016 ◽  
Vol 82 (22) ◽  
pp. 6557-6572 ◽  
Author(s):  
Yuka Kojima ◽  
Anikó Várnai ◽  
Takuya Ishida ◽  
Naoki Sunagawa ◽  
Dejan M. Petrovic ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Dynamic Viscosity ◽  
Brown Rot ◽  
Primary Cell Wall ◽  
Gloeophyllum Trabeum ◽  
Lytic Polysaccharide Monooxygenase ◽  
Content Type ◽  
Brown Rot Fungus ◽  
Sensitive Method ◽  
Polysaccharide Monooxygenase

ABSTRACTFungi secrete a set of glycoside hydrolases and lytic polysaccharide monooxygenases (LPMOs) to degrade plant polysaccharides. Brown-rot fungi, such asGloeophyllum trabeum, tend to have few LPMOs, and information on these enzymes is scarce. The genome ofG. trabeumencodes four auxiliary activity 9 (AA9) LPMOs (GtLPMO9s), whose coding sequences were amplified from cDNA. Due to alternative splicing, two variants ofGtLPMO9A seem to be produced, a single-domain variant,GtLPMO9A-1, and a longer variant,GtLPMO9A-2, which contains a C-terminal domain comprising approximately 55 residues without a predicted function. We have overexpressed the phylogenetically distinctGtLPMO9A-2 inPichia pastorisand investigated its properties. Standard analyses using high-performance anion-exchange chromatography–pulsed amperometric detection (HPAEC-PAD) and mass spectrometry (MS) showed thatGtLPMO9A-2 is active on cellulose, carboxymethyl cellulose, and xyloglucan. Importantly, compared to other known xyloglucan-active LPMOs,GtLPMO9A-2 has broad specificity, cleaving at any position along the β-glucan backbone of xyloglucan, regardless of substitutions. Using dynamic viscosity measurements to compare the hemicellulolytic action ofGtLPMO9A-2 to that of a well-characterized hemicellulolytic LPMO,NcLPMO9C fromNeurospora crassarevealed thatGtLPMO9A-2 is more efficient in depolymerizing xyloglucan. These measurements also revealed minor activity on glucomannan that could not be detected by the analysis of soluble products by HPAEC-PAD and MS and that was lower than the activity ofNcLPMO9C. Experiments with copolymeric substrates showed an inhibitory effect of hemicellulose coating on cellulolytic LPMO activity and did not reveal additional activities ofGtLPMO9A-2. These results provide insight into the LPMO potential ofG. trabeumand provide a novel sensitive method, a measurement of dynamic viscosity, for monitoring LPMO activity.IMPORTANCECurrently, there are only a few methods available to analyze end products of lytic polysaccharide monooxygenase (LPMO) activity, the most common ones being liquid chromatography and mass spectrometry. Here, we present an alternative and sensitive method based on measurement of dynamic viscosity for real-time continuous monitoring of LPMO activity in the presence of water-soluble hemicelluloses, such as xyloglucan. We have used both these novel and existing analytical methods to characterize a xyloglucan-active LPMO from a brown-rot fungus. This enzyme,GtLPMO9A-2, differs from previously characterized LPMOs in having broad substrate specificity, enabling almost random cleavage of the xyloglucan backbone.GtLPMO9A-2 acts preferentially on free xyloglucan, suggesting a preference for xyloglucan chains that tether cellulose fibers together. The xyloglucan-degrading potential ofGtLPMO9A-2 suggests a role in decreasing wood strength at the initial stage of brown rot through degradation of the primary cell wall.

scholarly journals Methoxy-deficient Structural Elements in Lignin of Sweetgum Decayed by a Brown-rot Fungus.

1970 ◽  
Vol 24 ◽  
pp. 3379-3390 ◽  
Author(s):  
T. Kent Kirk ◽  
Erich Adler ◽  
Olof Wahlberg ◽  
Erik Larsen ◽  
Akira Shimizu
Keyword(s):  
Brown Rot ◽  
Structural Elements ◽  
Brown Rot Fungus

scholarly journals Chemical characteristics of cultivated elderberry fruit

2008 ◽  
pp. 85-90 ◽  
Author(s):  
Jelena Vulic ◽  
Ljubo Vracar ◽  
Zdravko Sumic
Keyword(s):  
Vitamin C ◽  
Dry Matter ◽  
Reducing Sugars ◽  
Chemical Characteristics ◽  
Chemical Analyses ◽  
Surface Color ◽  
Pectic Acid ◽  
Mineral Substances ◽  
Reference Parameters ◽  
Physiological Value

This work is consered with the processing value of Elderberry fruit (berries) from domestic plantation selection (Horgos region). Chemical analyses of reference parameters (dry matter, acidity, pectin, pectic acid, protopectin, Capectat, ash, cellulose, total and reducing sugars, mineral substances, proteins and aminoacids, surface color, anthocyanins and vitamin C) confirmed high nutritional and physiological value of samples and full validity of work on this selection and production in plantation conditions.

Bioremediation of Chromium Contaminated Soil by a Brown-rot Fungus, Gloeophyllum sepiarium

2011 ◽  
Vol 6 (2) ◽  
pp. 166-171 ◽  
Author(s):  
Varenyam Achal ◽  
Deepika Kumari ◽  
Xiangliang Pan
Keyword(s):  
Contaminated Soil ◽  
Brown Rot ◽  
Brown Rot Fungus

New insights into the nature of glauconite

2020 ◽  
Vol 105 (5) ◽  
pp. 674-686 ◽  
Author(s):  
Adrián López-Quirós ◽  
Antonio Sánchez-Navas ◽  
Fernando Nieto ◽  
Carlota Escutia
Keyword(s):  
Electron Probe ◽  
Layer Growth ◽  
Chemical Characteristics ◽  
Chemical Analyses ◽  
X Ray Diffraction ◽  
K Uptake ◽  
X Ray ◽  
New Findings ◽  
Dioctahedral Mica ◽  
Interstratified Mineral

Abstract Glauconite must be assessed as mica-rich mica-smectite R3 interstratified mineral, with the pure end-member mica also having intrinsic K-deficient chemical characteristics (K+ ~ 0.8 apfu). This assertion is in accordance with our X-ray diffraction (XRD) and high-resolution tranmission electron microscopy (HRTEM) studies and chemical analyses by electron probe microanalysis (EPMA) of mature glauconites in Cenozoic Antarctic sediments that indicate that: (1) It consists of a glauconite-smectite (R3 ordered) mixed-layer silicate, composed mainly of mica-type layers (>90%), but displaying slightly different proportions of Fe(III)-smectite layers (<10%). (2) More mature glaucony grains are characterized by major K+ and VIFe2+ (mica layers) and minor VIFe3+ (smectite layers) content in the interstratified glauconite-smectite. (3) Potassium is stabilized at the interlayer site by the octahedrally coordinated Fe2+. (4) Microtexture of the glauconite crystals are comparable with those of other micas and illite minerals, with straight, defect-free lattice fringes of ~10 Å spacings glauconite packets characteristic of mica with minor interstratified poorly crystalline smectite layers. In addition, our new findings give insights into the glauconitization process and at the same time investigate the potassium-deficient character of the dioctahedral mica “glauconite.” These findings show that glauconite crystallizes by a layer-growth mechanism at the expense of a poorly crystalline smectite precursor and that smectiteto-glauconite transformations are accompanied by a gradually higher octahedral charge deficiency (Fe2+/Fe3+) stabilized by K+ uptake into the interlayer sheet.

Bioorganosolv pretreatments of P. radiata by a brown rot fungus (Gloephyllum trabeum) and ethanolysis

2010 ◽  
Vol 47 (1-2) ◽  
pp. 11-16 ◽  
Author(s):  
Mariel Monrroy ◽  
Jeniffer Ibañez ◽  
Victoria Melin ◽  
Jaime Baeza ◽  
Regis Teixeira Mendonça ◽  
...  
Keyword(s):  
Brown Rot ◽  
Brown Rot Fungus
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