Production of poly (3-hydroxybutyrate) and extracellular polymeric substances from glycerol by the acidophile Acidiphilium cryptum

Ernesto González*, Camila Zuleta, Guiselle Zamora, Nataly Maturana, Belén Ponce, María Virginia Rivero, Alberto Rodríguez, Juan Pablo Soto, Felipe Scott, Álvaro Díaz-Barrera

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

Acidiphilium cryptum is an acidophilic, heterotrophic, and metallotolerant bacteria able to use dissolved oxygen or Fe(III) as an electron sink. The ability of this extremophile to accumulate poly(3-hydroxybutyrate) (PHB) and secrete extracellular polymeric substances (EPS) has also been reported. Hence, the aim of this work is to characterize the production of PHB and EPS by the wild strain DSM2389 using glycerol in shaken flasks and bioreactor. Results showed that maximum PHB accumulation (37–42% w/w) was obtained using glycerol concentrations of 9 and 15 g L−1, where maximum dry cell weight titers reached 3.6 and 3.9 g L−1, respectively. The culture in the bioreactor showed that PHB accumulation takes place under oxygen limitation, while the redox potential of the culture medium could be used for online monitoring of the PHB production. Recovered EPS was analyzed by Fourier-transform infrared spectroscopy and subjected to gas chromatography—mass spectrometry after cleavage and derivatization steps. These analyses showed the presence of sugars which were identified as mannose, rhamnose and glucose, in a proportion near to 3.2:2.3:1, respectively. Since glycerol had not been used in previous works, these findings suggest the potential of A. cryptum to produce biopolymers from this compound at a large scale with a low risk of microbial contamination due to the low pH of the fermentation process.

Original languageEnglish
Article number30
JournalExtremophiles
Volume27
Issue number3
DOIs
StatePublished - Dec 2023

Bibliographical note

Publisher Copyright:
© 2023, The Author(s), under exclusive licence to Springer Nature Japan KK, part of Springer Nature.

Keywords

  • Acidiphilium cryptum
  • Acidophile
  • Extracellular polymeric substance
  • Extremophile
  • Glycerol
  • poly(3-hydroxybutyrate)

Fingerprint

Dive into the research topics of 'Production of poly (3-hydroxybutyrate) and extracellular polymeric substances from glycerol by the acidophile Acidiphilium cryptum'. Together they form a unique fingerprint.

Cite this