Bacterial conversion of depolymerized Kraft lignin
Ravi, Krithika LU ; Abdelaziz, Omar Y. LU ; Nöbel, Matthias ; García-hidalgo, Javier LU ; Gorwa-grauslund, Marie F. LU ; Hulteberg, Christian P. LU
and Lidén, Gunnar
LU
(2019)
In Biotechnology for Biofuels
12.
- Abstract
- Background
Lignin is a potential feedstock for microbial conversion into various chemicals. However, the microbial degradation rate of native or technical lignin is low, and chemical depolymerization is needed to obtain reasonable conversion rates. In the current study, nine bacterial strains belonging to the Pseudomonas and Rhodococcus genera were evaluated for their ability to grow on alkaline-treated softwood lignin as a sole carbon source.
Results
Pseudomonas fluorescens DSM 50090 and Rhodococcus opacus DSM1069 showed the best growth of the tested species on plates with lignin. Further evaluation of P. fluorescens and R. opacus was made in liquid cultivations with depolymerized softwood Kraft lignin (DL) at a... (More) - Background
Lignin is a potential feedstock for microbial conversion into various chemicals. However, the microbial degradation rate of native or technical lignin is low, and chemical depolymerization is needed to obtain reasonable conversion rates. In the current study, nine bacterial strains belonging to the Pseudomonas and Rhodococcus genera were evaluated for their ability to grow on alkaline-treated softwood lignin as a sole carbon source.
Results
Pseudomonas fluorescens DSM 50090 and Rhodococcus opacus DSM1069 showed the best growth of the tested species on plates with lignin. Further evaluation of P. fluorescens and R. opacus was made in liquid cultivations with depolymerized softwood Kraft lignin (DL) at a concentration of 1 g/L. Size-exclusion chromatography (SEC) showed that R. opacus consumed most of the available lower-molecular weight compounds (approximately 0.1–0.4 kDa) in the DL, but the weight distribution of larger fractions was almost unaffected. Importantly, the consumed compounds included guaiacol—one of the main monomers in the DL. SEC analysis of P. fluorescens culture broth, in contrast, did not show a large conversion of low-molecular weight compounds, and guaiacol remained unconsumed. However, a significant shift in molecular weight distribution towards lower average weights was seen after cultivation with P. fluorescens.
Conclusions
Rhodococcus opacus and P. fluorescens were identified as two potential microbial candidates for the conversion/consumption of base-catalyzed depolymerized lignin, acting on low- and high-molecular weight lignin fragments, respectively. These findings will be of relevance for designing bioconversion of softwood Kraft lignin.
(Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/aa655b01-e162-4eaa-9e6f-e99f8646a0a1
- author
- Ravi, Krithika
LU
; Abdelaziz, Omar Y.
LU
; Nöbel, Matthias
; García-hidalgo, Javier
LU
; Gorwa-grauslund, Marie F.
LU
; Hulteberg, Christian P.
LU
and Lidén, Gunnar
LU
- organization
- publishing date
- 2019-03-16
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Biotechnology for Biofuels
- volume
- 12
- article number
- 56
- publisher
- BioMed Central (BMC)
- external identifiers
-
- scopus:85063078468
- pmid:30923564
- ISSN
- 1754-6834
- DOI
- 10.1186/s13068-019-1397-8
- language
- English
- LU publication?
- yes
- id
- aa655b01-e162-4eaa-9e6f-e99f8646a0a1
- date added to LUP
- 2019-03-19 09:55:29
- date last changed
- 2023-11-18 16:50:04
@article{aa655b01-e162-4eaa-9e6f-e99f8646a0a1,
abstract = {{Background<br/><br/>Lignin is a potential feedstock for microbial conversion into various chemicals. However, the microbial degradation rate of native or technical lignin is low, and chemical depolymerization is needed to obtain reasonable conversion rates. In the current study, nine bacterial strains belonging to the Pseudomonas and Rhodococcus genera were evaluated for their ability to grow on alkaline-treated softwood lignin as a sole carbon source.<br/>Results<br/><br/>Pseudomonas fluorescens DSM 50090 and Rhodococcus opacus DSM1069 showed the best growth of the tested species on plates with lignin. Further evaluation of P. fluorescens and R. opacus was made in liquid cultivations with depolymerized softwood Kraft lignin (DL) at a concentration of 1 g/L. Size-exclusion chromatography (SEC) showed that R. opacus consumed most of the available lower-molecular weight compounds (approximately 0.1–0.4 kDa) in the DL, but the weight distribution of larger fractions was almost unaffected. Importantly, the consumed compounds included guaiacol—one of the main monomers in the DL. SEC analysis of P. fluorescens culture broth, in contrast, did not show a large conversion of low-molecular weight compounds, and guaiacol remained unconsumed. However, a significant shift in molecular weight distribution towards lower average weights was seen after cultivation with P. fluorescens.<br/>Conclusions<br/><br/>Rhodococcus opacus and P. fluorescens were identified as two potential microbial candidates for the conversion/consumption of base-catalyzed depolymerized lignin, acting on low- and high-molecular weight lignin fragments, respectively. These findings will be of relevance for designing bioconversion of softwood Kraft lignin.<br/>}},
author = {{Ravi, Krithika and Abdelaziz, Omar Y. and Nöbel, Matthias and García-hidalgo, Javier and Gorwa-grauslund, Marie F. and Hulteberg, Christian P. and Lidén, Gunnar}},
issn = {{1754-6834}},
language = {{eng}},
month = {{03}},
publisher = {{BioMed Central (BMC)}},
series = {{Biotechnology for Biofuels}},
title = {{Bacterial conversion of depolymerized Kraft lignin}},
url = {{http://dx.doi.org/10.1186/s13068-019-1397-8}},
doi = {{10.1186/s13068-019-1397-8}},
volume = {{12}},
year = {{2019}},
}