Chemoenzymatic Fractionation and Characterization of Pretreated Birch Outer Bark

Abstract Bark wastes today are viewed as a high-value resource for biorefinery due to their chemical richness and diversity. This work presents a comprehensive chemical characterization of the inner bark and the outer bark of Eucalyptus camaldulensis cultivated in Algeria. The extractives were first isolated with an Accelerated Solvent Extractor (ASE) and then analyzed by Gas Chromatography-Mass Spectrometry (GC-MS). The content of pre-extracted bark in cellulosic polysaccharide and free sugar monomers was determined by Gas Chromatography (GC). The hemicellulose composition and amount was determined after the acid methanolysis and GC. The amount of lignin was determined gravimetrically by the Klason lignin method and the acid soluble lignin was determined by the UV method. Formic and acetic acids in the bark were determined by HPLC after alkaline hydrolysis. It was found that the extractives content were similar in the outer bark (0.85%) and the inner bark (0.88%). The cellulose content was higher in the outer bark (33.4%) than in the inner bark (28.7%). Lignin and the total hemicellulose contents were more abundant in the outer bark (31.7, 26.2%) than in the inner bark (28.6, 19.3%) whereas, sugar monomers were more abundant in the inner bark (4.4%) than in the outer bark (3.8%). The variation in acetic and formic acids and ash contents between the outer bark (1.5, 0.006 and 2.5%) and the inner bark (1.3, 0.005 and 2.4%) was small. The obtained results showed that the bark can be considered a suitable feedstock for lignocellulosic biorefinery and also for the extraction of bioactive compounds that can be used in different sectors.

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Extraction and chemical characterization of Norway spruce inner and outer bark

Nordic Pulp & Paper Research Journal ◽

10.3183/npprj-2012-27-01-p006-017 ◽

2012 ◽

Vol 27 (1) ◽

pp. 6-17 ◽

Cited By ~ 43

Author(s):

Jens Krogell ◽

Bjarne Holmbom ◽

Andrey Pranovich ◽

Jarl Hemming ◽

Stefan Willför

Keyword(s):

Norway Spruce ◽

Chemical Characterization ◽

Hot Water ◽

Second Step ◽

Pectic Polysaccharides ◽

Outer Bark ◽

Inner Bark ◽

Chemical Character ◽

Chemical Utilization

Abstract Possible chemical utilization of bark requires appropriate knowledge of its composition. Extraction of valuable components before burning is an interesting option for utilization of bark. Here, Norway spruce inner and outer bark were extracted separately with a successive series of solvents of increasing polarity and the extracts, as well as the residues, were analyzed to obtain an overall picture of the bark composition. The lipophilic extractives contained the same major components as found in wood. Inner bark contained over 10% of stilbene glucosides with piceatannol (astringenin) as the main stilbene. Tannins of the proanthocyanidin type were extracted with hot water. Further extraction with pressurized hot water at 140°C or 160°C yielded 11-14% of non-cellulosic polysaccharides, on original bark basis, with pectic polysaccharides built up of arabinose, galacturonic acid and rhamnose dominating. Inner bark contained two times more cellulose than outer bark, but the opposite was true for lignin, determined as Klason “lignin”. Among the potentially valuable components, stilbene glucosides could be extracted with water even at low temperatures, while tannins could be extracted with hot water in a second step. The pectic polysaccharides are also of potential interest and should be studied further. The amount and true chemical character of lignin is also not yet fully elucidated.

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Characterization of suberinic acids from birch outer bark as bio-based adhesive in wood composites

International Journal of Adhesion and Adhesives ◽

10.1016/j.ijadhadh.2021.102989 ◽

2022 ◽

Vol 112 ◽

pp. 102989

Author(s):

Janis Rizhikovs ◽

Prans Brazdausks ◽

Aigars Paze ◽

Ramunas Tupciauskas ◽

Juris Grinins ◽

...

Keyword(s):

Wood Composites ◽

Outer Bark

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CHARACTERIZATION OF ANTIOXIDANT ACTIVITY AND TOTAL PHENOLIC COMPOUND CONTENT OF BIRCH OUTER BARK EXTRACTS USING MICRO PLATE ASSAY

Environment Technology Resources Proceedings of the International Scientific and Practical Conference ◽

10.17770/etr2017vol1.2554 ◽

2017 ◽

Vol 1 ◽

pp. 197 ◽

Cited By ~ 1

Author(s):

Ilva Nakurte ◽

Kristaps Stankus ◽

Inguss Virsis ◽

Aigars Paze ◽

Janis Rizhikovs

Keyword(s):

Betula Pendula ◽

Radical Scavenging Activity ◽

Antioxidant Properties ◽

Radical Scavenging ◽

Total Phenolic ◽

Outer Bark ◽

Dry Extract ◽

Plate Assay ◽

Ethanol Extracts

In modern plants, 2.7 to 2.8 m3 of solid volume veneer blocks are consumed to produce 1 m3 of plywood. After the hydrothermal treatment and debarking of blocks, waste bark is obtained, which makes up 12.5% of the wood mass, while 16-20% of bark is composed of birch outer bark (BOB). Recalculating, BOB makes up 2.0-3.4% of the veneer log mass. Bark is currently burned in boiler houses that is not rational. BOB contains large amount of valuable extractives (up to 34% from o.d. BOB) consisting of various secondary metabolites such as terpenes, flavonoids, hydrocarbons, polyphenols, tannins etc. BOB extractives exhibit antioxidant properties as well as wound-healing and anti-inflammatory activity. The objective of this paper was to compare amount of total phenolic content (TPC) and antiradical activity (ARA) in ethanol extracts from silver birch (Betula pendula Roth.) outer bark using micro plate assay. Among 11 fractions, fraction of average BOB had the highest DPPH free radical scavenging activity with IC50 of 39.28 μg/mL and the highest TPC 7.42 ± 0.52 g GAE/100 g of dry extract.

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Chemical characterization of cork and phloem from Douglas fir outer bark

Holzforschung ◽

10.1515/hf-2015-0119 ◽

2016 ◽

Vol 70 (5) ◽

pp. 475-483 ◽

Cited By ~ 17

Author(s):

Joana P.A. Ferreira ◽

Isabel Miranda ◽

Jorge Gominho ◽

Helena Pereira

Keyword(s):

Fatty Acids ◽

Chemical Composition ◽

Pseudotsuga Menziesii ◽

Chemical Characterization ◽

Quercus Suber ◽

Minor Components ◽

Outer Bark ◽

Lipophilic Extract ◽

Alkanoic Acids

Abstract Cork and phloem from Pseudotsuga menziesii outer bark were separated, fractionated and the 40- to 60-mesh fractions chemically analyzed. Cork and phloem showed a different grinding behavior with the highest yields for cork and phloem, respectively, for the 40- to 60-mesh fraction (31.4%) and the <0.180-mm fraction (49.2%). Cork chemical composition was (% o.d. mass): ash 0.9%; extractives 29.2% (mostly polar, 23.5%); lignin 16.8%, and suberin 36.2%. Polysaccharides (16.9%) contained glucose (55.4% of total neutral carbohydrates), xylose (13.3%), mannose, arabinose, and galactose as minor components. Lipophilic and suberin extracts from cork and phloem were analyzed by GC-MS, directly and after alkaline hydrolysis. In cork, catechin was the major compound identified in the lipophilic extract, accompanied by ferulic acid and acylglycerols. In phloem, β-sitosterol was the major compound. The content of fatty alcohols and fatty acids increased after hydrolysis confirming their esterification in both extracts. Suberin from P. menziesii cork is rich in saturated ω-hydroxyacids (ω-hydroxyacids 36.2%, α,ω-diacids 18.6%, alkanoic acids 6.2%, and alkanols 8.7%), being different from suberin of Quercus suber where α,ω-diacids are dominant.

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Virgin Natural Cork Characterization as a Sustainable Material for Use in Acoustic Solutions

Sustainability ◽

10.3390/su13094976 ◽

2021 ◽

Vol 13 (9) ◽

pp. 4976

Author(s):

Juan Miguel Barrigón Morillas ◽

David Montes González ◽

Rosendo Vílchez-Gómez ◽

Valentín Gómez Escobar ◽

Rubén Maderuelo-Sanz ◽

...

Keyword(s):

Absorption Coefficient ◽

Sound Absorption ◽

Scientific Literature ◽

Outer Bark ◽

Reverberation Chamber ◽

Frequency Bands ◽

Sustainable Material ◽

Natural Cork ◽

Sheep Wool

A characterization of the sound absorption of a sustainable material with scarce current use such as natural virgin cork is presented in this paper in order to explore further possible applications in the design of acoustic solutions. Different samples of virgin cork not bonded and various decorative panel formats were tested under random sound incidence conditions in a standardized reverberation chamber. The samples in which the outer bark of the cork was facing upwards showed a better behavior as an acoustic absorber, with sound absorption coefficient values generally greater than 0.6 for frequency bands between 1 and 5 kHz. The results obtained were compared with samples of some recycled materials available in the scientific literature, such as sheep wool and PET.

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Morphological Characterization of Mycobacteriophage R1

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051281 ◽

1974 ◽

Vol 32 ◽

pp. 254-255

Author(s):

B. L. Soloff ◽

T. A. Rado

Keyword(s):

Carbon Source ◽

Stationary Phase ◽

Growth Phase ◽

Minimal Medium ◽

Morphological Characterization ◽

Logarithmic Growth Phase ◽

Complete Lysis ◽

Lysogenic Culture ◽

Logarithmic Growth

Mycobacteriophage R1 was originally isolated from a lysogenic culture of M. butyricum. The virus was propagated on a leucine-requiring derivative of M. smegmatis, 607 leu−, isolated by nitrosoguanidine mutagenesis of typestrain ATCC 607. Growth was accomplished in a minimal medium containing glycerol and glucose as carbon source and enriched by the addition of 80 μg/ ml L-leucine. Bacteria in early logarithmic growth phase were infected with virus at a multiplicity of 5, and incubated with aeration for 8 hours. The partially lysed suspension was diluted 1:10 in growth medium and incubated for a further 8 hours. This permitted stationary phase cells to re-enter logarithmic growth and resulted in complete lysis of the culture.

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AEM analysis of crystallization in Ti-based amorphous alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075142 ◽

1983 ◽

Vol 41 ◽

pp. 270-271

Author(s):

A.R. Pelton ◽

A.F. Marshall ◽

Y.S. Lee

Keyword(s):

Magnetic Properties ◽

Amorphous Alloys ◽

Amorphous Materials ◽

Isothermal Annealing ◽

Amorphous Matrix ◽

Nucleation And Growth ◽

Current Interest ◽

Amorphous Films ◽

Electrical And Magnetic Properties

Amorphous materials are of current interest due to their desirable mechanical, electrical and magnetic properties. Furthermore, crystallizing amorphous alloys provides an avenue for discerning sequential and competitive phases thus allowing access to otherwise inaccessible crystalline structures. Previous studies have shown the benefits of using AEM to determine crystal structures and compositions of partially crystallized alloys. The present paper will discuss the AEM characterization of crystallized Cu-Ti and Ni-Ti amorphous films.Cu60Ti40: The amorphous alloy Cu60Ti40, when continuously heated, forms a simple intermediate, macrocrystalline phase which then transforms to the ordered, equilibrium Cu3Ti2 phase. However, contrary to what one would expect from kinetic considerations, isothermal annealing below the isochronal crystallization temperature results in direct nucleation and growth of Cu3Ti2 from the amorphous matrix.

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Characterization of Coherent, Ordered Precipitates in Nickel-Base Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071168 ◽

1973 ◽

Vol 31 ◽

pp. 144-145

Author(s):

B. H. Kear ◽

J. M. Oblak

Keyword(s):

Stable Phase ◽

Nickel Base Superalloy ◽

Alloy 718 ◽

Commercial Alloy ◽

Precipitate Morphology ◽

Continuous Precipitation ◽

Nickel Base ◽

Base Superalloy ◽

Strengthening Precipitate

A nickel-base superalloy is essentially a Ni/Cr solid solution hardened by additions of Al (Ti, Nb, etc.) to precipitate a coherent, ordered phase. In most commercial alloy systems, e.g. B-1900, IN-100 and Mar-M200, the stable precipitate is Ni3 (Al,Ti) γ′, with an LI2structure. In A lloy 901 the normal precipitate is metastable Nis Ti3 γ′ ; the stable phase is a hexagonal Do2 4 structure. In Alloy 718 the strengthening precipitate is metastable γ″, which has a body-centered tetragonal D022 structure.Precipitate MorphologyIn most systems the ordered γ′ phase forms by a continuous precipitation re-action, which gives rise to a uniform intragranular dispersion of precipitate particles. For zero γ/γ′ misfit, the γ′ precipitates assume a spheroidal.

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