Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Lignocellulose Degradation by Soil Micro-organisms
KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.ORCID iD: 0000-0001-8135-588X
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Lignocellulosic biomass is a sustainable resource with abundant reserves. Compared to petroleum ‐ based products, the biomass ‐ derived polymers and chemicals give better environmental profiles. A lot of research interest is focused on understanding the lignocellulose structures.

Lignin, among the three major wood components, represents most difficulty for microbial degradation because of its complex structure and because cross ‐ linking to hemicellulose makes wood such a compact structure. Nevertheless, wood is naturally degraded by wood ‐ degrading micro ‐ organisms and modified and partly degraded residual of lignin goes into soil. Therefore soil serves as a good environment in which to search for special lignin ‐ degraders. In this thesis, different types of lignin have been used as sole carbon sources to screen for lignin ‐ degrading soil micro ‐ organisms. Eleven aerobic and three anaerobic microbe strains have been isolated and identified as able to grow on lignin. The lignin degradation patterns of selected strains have been studied and these partly include an endwise cleavage of  β‐ O ‐ 4 bonds in lignin and is more complex than simple hydrolytic degradation.

As lignin exists in wood covalently bonded to hemicellulose, one isolated microbe strain, Phoma herbarum, has also been studied with regards to its ability to degrade covalent lignin polysaccharide networks (LCC). The results show that its culture filtrate can attack lignin ‐ polysaccharide networks in a manner different from that of the commercial enzyme product, Gammanase, possibly by selective cleavage of phenyl glucoside bonds. The effects on LCC of Phoma herbarum also enhance polymer extractability. Hot ‐ water extraction of a culture filtrate of Phoma herbarum ‐ treated fiberized spruce wood material gave an amount of extracted galactoglucomannan more than that given by the Gammanase ‐ treated material and non ‐ enzyme ‐ treated material.

Over millions of years of natural evolution, micro ‐ organisms on the one hand develop so that they can degrade all wood components to get energy for growth, while plants on the other hand also continuously develop to defend from microbial attack. Compared with lignin and cellulose, hemicelluloses as major components of plant cell walls, are much more easily degraded, but hemicelluloses differ from cellulose in that they are acetylated to different extents. The biological functions of acetylation are not completely understood, but it is suggested is that one function is to decrease the microbial degradability of cell walls. By cultivation of soil micro ‐ organisms using mannans acetylated to deffernent degrees as sole carbon source on agar plates, we were able to see significant trends where the resistance towards microbial degradation of glucomannan and galactomannan increased with increasing degree of acetylation. Possible mechanisms and the technological significance of this are discussed. Tailoring the degree of acetylation of polysaccharide materials might slow down the biodegradation, making it possible to design a material with a degradation rate suited to its application.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2016. , 59 p.
Series
TRITA-CHE-Report, ISSN 1654-1081 ; 2016:10
National Category
Polymer Technologies Biocatalysis and Enzyme Technology Microbiology Polymer Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-182336ISBN: 978-91-7595-868-2 OAI: oai:DiVA.org:kth-182336DiVA: diva2:904230
Public defence
2016-03-18, Kollegiesalen, Brinellvägen 8, KTH, Stockholm, 10:00 (English)
Opponent
Supervisors
Funder
Knut and Alice Wallenberg Foundation
Note

QC 20160223

Available from: 2016-02-23 Created: 2016-02-18 Last updated: 2017-03-02Bibliographically approved
List of papers
1. Isolation and identification of microorganisms from soil able to live on lignin as a carbon source and to produce enzymes which cleave beta-O-4 bond in a lignin model compound
Open this publication in new window or tab >>Isolation and identification of microorganisms from soil able to live on lignin as a carbon source and to produce enzymes which cleave beta-O-4 bond in a lignin model compound
Show others...
2012 (English)In: Cellulose Chemistry and Technology, ISSN 0576-9787, Vol. 46, no 3-4, 227-242 p.Article in journal (Refereed) Published
Abstract [en]

Several strains of fungi were isolated and identified from Scandinavian soil using agar plates with lignin as a carbon source. The strains grew significantly faster on this medium than on control plates without lignin. Different types of technical lignins were used, some of which contained trace amounts of sugars, even if the increased growth rate seemed not related to the sugar content. Some strains were cultivated in shaking flask cultures with lignin as a carbon source, with lignin apparently consumed by microbes - while accumulation of the microorganism biomass occurred. The cell-free filtrates of these cultures could reduce the apparent molecular weights of lignosulphonates, while the culture filtrate of one strain could cleave the beta-O-4 bond in a lignin model compound.

Keyword
lignin biodegradation, carbon source, soil microorganisms, extracellular enzymes, beta-O-4 bond
National Category
Chemical Engineering
Identifiers
urn:nbn:se:kth:diva-101134 (URN)000306779000010 ()2-s2.0-84864568077 (Scopus ID)
Note

QC 20120824

Available from: 2012-08-24 Created: 2012-08-23 Last updated: 2017-12-07Bibliographically approved
2. Isolation of exceedingly low oxygen consuming fungal strains able to utilize lignin as carbon source
Open this publication in new window or tab >>Isolation of exceedingly low oxygen consuming fungal strains able to utilize lignin as carbon source
(English)In: Cellulose Chemistry and Technology, ISSN 0576-9787Article in journal (Refereed) Accepted
National Category
Chemical Process Engineering Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-182253 (URN)
Note

QS 2016

Available from: 2016-02-18 Created: 2016-02-18 Last updated: 2017-11-30Bibliographically approved
3. Phoma herbarum, a soil fungus able to grow on natural lignin and synthetic lignin (DHP) as sole carbon source and cause lignin degradation
Open this publication in new window or tab >>Phoma herbarum, a soil fungus able to grow on natural lignin and synthetic lignin (DHP) as sole carbon source and cause lignin degradation
(English)Manuscript (preprint) (Other academic)
National Category
Polymer Technologies
Identifiers
urn:nbn:se:kth:diva-182261 (URN)10.1007/s10295-016-1783-1 (DOI)
Note

QC 20160818

Available from: 2016-02-18 Created: 2016-02-18 Last updated: 2016-11-01Bibliographically approved
4.
The record could not be found. The reason may be that the record is no longer available or you may have typed in a wrong id in the address field.
5. Culture Filtrates from a Soil Organism Enhances Extractability of Polymers from Fiberised Spruce Wood
Open this publication in new window or tab >>Culture Filtrates from a Soil Organism Enhances Extractability of Polymers from Fiberised Spruce Wood
(English)Manuscript (preprint) (Other academic)
National Category
Polymer Technologies Biochemistry and Molecular Biology Microbiology
Identifiers
urn:nbn:se:kth:diva-182279 (URN)
Note

QS 2016

Available from: 2016-02-18 Created: 2016-02-18 Last updated: 2016-02-23Bibliographically approved
6. The Degree Of Acetylation Affects The Microbial Degradability Of Hemicelluloses
Open this publication in new window or tab >>The Degree Of Acetylation Affects The Microbial Degradability Of Hemicelluloses
Show others...
(English)Manuscript (preprint) (Other academic)
National Category
Polymer Technologies Microbiology
Identifiers
urn:nbn:se:kth:diva-182286 (URN)
Note

QS 2016

Available from: 2016-02-18 Created: 2016-02-18 Last updated: 2016-02-23Bibliographically approved

Open Access in DiVA

Thesis(1166 kB)633 downloads
File information
File name FULLTEXT01.pdfFile size 1166 kBChecksum SHA-512
5bc40066746e35e474285e47a556aa60d9c31647968887cfd36dcf461fa5da8013e0b8f8ebf4f972116f9a2044a58f90130ee7ef88dad63963d27f0edc7feddb
Type fulltextMimetype application/pdf

Authority records BETA

Bi, Ran

Search in DiVA

By author/editor
Bi, Ran
By organisation
Wood Chemistry and Pulp TechnologyWallenberg Wood Science Center
Polymer TechnologiesBiocatalysis and Enzyme TechnologyMicrobiologyPolymer Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 633 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 734 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf