Cargando…

Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations

BACKGROUND: In order to establish a cost-efficient biodiesel biorefinery, valorization of its main by-product, crude glycerol, is imperative. Recently, Ustilago trichophora TZ1 was found to efficiently produce malic acid from glycerol. By adaptive laboratory evolution and medium optimization, titer...

Descripción completa

Detalles Bibliográficos
Autores principales: Zambanini, Thiemo, Kleineberg, Wiebke, Sarikaya, Eda, Buescher, Joerg M., Meurer, Guido, Wierckx, Nick, Blank, Lars M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4930609/
https://www.ncbi.nlm.nih.gov/pubmed/27375775
http://dx.doi.org/10.1186/s13068-016-0553-7
_version_ 1782440770743042048
author Zambanini, Thiemo
Kleineberg, Wiebke
Sarikaya, Eda
Buescher, Joerg M.
Meurer, Guido
Wierckx, Nick
Blank, Lars M.
author_facet Zambanini, Thiemo
Kleineberg, Wiebke
Sarikaya, Eda
Buescher, Joerg M.
Meurer, Guido
Wierckx, Nick
Blank, Lars M.
author_sort Zambanini, Thiemo
collection PubMed
description BACKGROUND: In order to establish a cost-efficient biodiesel biorefinery, valorization of its main by-product, crude glycerol, is imperative. Recently, Ustilago trichophora TZ1 was found to efficiently produce malic acid from glycerol. By adaptive laboratory evolution and medium optimization, titer and rate could be improved significantly. RESULTS: Here we report on the investigation of this strain in fed-batch bioreactors. With pH controlled at 6.5 (automatic NaOH addition), a titer of 142 ± 1 g L(−1) produced at an overall rate of 0.54 ± 0.00 g L(−1) h(−1) was reached by optimizing the initial concentrations of ammonium and glycerol. Combining the potential of bioreactors and CaCO(3) as buffer system, we were able to increase the overall production rate to 0.74 ± 0.06 g L(−1) h(−1) with a maximum production rate of 1.94 ± 0.32 g L(−1) reaching a titer of 195 ± 15 g L(−1). The initial purification strategy resulted in 90 % pure calcium malate as solid component. Notably, the fermentation is not influenced by an increased temperature of up to 37 °C, which reduces the energy required for cooling. However, direct acid production is not favored as at a lowered pH value of pH 4.5 the malic acid titer decreased to only 9 ± 1 g L(−1). When using crude glycerol as substrate, only the product to substrate yield is decreased. The results are discussed in the context of valorizing glycerol with Ustilaginaceae. CONCLUSIONS: Combining these results reveals the potential of U.trichophora TZ1 to become an industrially applicable production host for malic acid from biodiesel-derived glycerol, thus making the overall biodiesel production process economically and ecologically more feasible.
format Online
Article
Text
id pubmed-4930609
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher BioMed Central
record_format MEDLINE/PubMed
spelling pubmed-49306092016-07-03 Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations Zambanini, Thiemo Kleineberg, Wiebke Sarikaya, Eda Buescher, Joerg M. Meurer, Guido Wierckx, Nick Blank, Lars M. Biotechnol Biofuels Research BACKGROUND: In order to establish a cost-efficient biodiesel biorefinery, valorization of its main by-product, crude glycerol, is imperative. Recently, Ustilago trichophora TZ1 was found to efficiently produce malic acid from glycerol. By adaptive laboratory evolution and medium optimization, titer and rate could be improved significantly. RESULTS: Here we report on the investigation of this strain in fed-batch bioreactors. With pH controlled at 6.5 (automatic NaOH addition), a titer of 142 ± 1 g L(−1) produced at an overall rate of 0.54 ± 0.00 g L(−1) h(−1) was reached by optimizing the initial concentrations of ammonium and glycerol. Combining the potential of bioreactors and CaCO(3) as buffer system, we were able to increase the overall production rate to 0.74 ± 0.06 g L(−1) h(−1) with a maximum production rate of 1.94 ± 0.32 g L(−1) reaching a titer of 195 ± 15 g L(−1). The initial purification strategy resulted in 90 % pure calcium malate as solid component. Notably, the fermentation is not influenced by an increased temperature of up to 37 °C, which reduces the energy required for cooling. However, direct acid production is not favored as at a lowered pH value of pH 4.5 the malic acid titer decreased to only 9 ± 1 g L(−1). When using crude glycerol as substrate, only the product to substrate yield is decreased. The results are discussed in the context of valorizing glycerol with Ustilaginaceae. CONCLUSIONS: Combining these results reveals the potential of U.trichophora TZ1 to become an industrially applicable production host for malic acid from biodiesel-derived glycerol, thus making the overall biodiesel production process economically and ecologically more feasible. BioMed Central 2016-07-02 /pmc/articles/PMC4930609/ /pubmed/27375775 http://dx.doi.org/10.1186/s13068-016-0553-7 Text en © The Author(s) 2016 Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research
Zambanini, Thiemo
Kleineberg, Wiebke
Sarikaya, Eda
Buescher, Joerg M.
Meurer, Guido
Wierckx, Nick
Blank, Lars M.
Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations
title Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations
title_full Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations
title_fullStr Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations
title_full_unstemmed Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations
title_short Enhanced malic acid production from glycerol with high-cell density Ustilago trichophora TZ1 cultivations
title_sort enhanced malic acid production from glycerol with high-cell density ustilago trichophora tz1 cultivations
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4930609/
https://www.ncbi.nlm.nih.gov/pubmed/27375775
http://dx.doi.org/10.1186/s13068-016-0553-7
work_keys_str_mv AT zambaninithiemo enhancedmalicacidproductionfromglycerolwithhighcelldensityustilagotrichophoratz1cultivations
AT kleinebergwiebke enhancedmalicacidproductionfromglycerolwithhighcelldensityustilagotrichophoratz1cultivations
AT sarikayaeda enhancedmalicacidproductionfromglycerolwithhighcelldensityustilagotrichophoratz1cultivations
AT buescherjoergm enhancedmalicacidproductionfromglycerolwithhighcelldensityustilagotrichophoratz1cultivations
AT meurerguido enhancedmalicacidproductionfromglycerolwithhighcelldensityustilagotrichophoratz1cultivations
AT wierckxnick enhancedmalicacidproductionfromglycerolwithhighcelldensityustilagotrichophoratz1cultivations
AT blanklarsm enhancedmalicacidproductionfromglycerolwithhighcelldensityustilagotrichophoratz1cultivations