Log in

Modeling of poly-β-hydroxybutyrate production by Bacillus subtilis and its use for feed-forward bioreactor studies

  • Biotechnological Products and Process Engineering
  • Published:
Applied Microbiology and Biotechnology Aims and scope Submit manuscript

Abstract  

Successful scale-up of Bacillus subtilis culture for poly-β-hydroxybutyrate (PHB) production was performed in 5-l stirred-tank reactor using batch, fed-batch, and two-stage culture strategies. The kinetics of biomass production, substrate consumption, and PHB production were established in the stirred tank bioreactor in all the studies. A mathematical model was developed to investigate the role of limiting substrate on overall culture metabolism. A fed-batch strategy was predicted on the basis of computer simulations, for maximum PHB production. This was performed by extrapolation of batch model for predicting the feeding rate and suitable time of feeding. Substrate inhibition was studied and the substrate inhibition terms were incorporated in the model. The maximum cell biomass concentration in batch culture (24 h) and fed-batch culture (30 h) was 1.79 ± 0.03 g/l on dry cell weight (DCW) basis and 1.66 ± 0.050 g/l on DCW basis and the corresponding PHB content was 68.71% and 85.54% of DCW, respectively. Glucose was found to be the major limiting nutrient during the bioreactor culture. A two-stage culture, where cells were first grown in stage I in LBG media containing excess carbon and thereafter in stage II in OM media, showed biomass production of 1.95 ± 0.045 g/l at 4 h and PHB production of 93.33% of DCW at 16 h. A 9% increase in growth and 25% increase in PHB yield were obtained using two-stage culture with computer-simulated feeding strategy in the 5 l reactor. Oxygen limitation was overcome in modified two-stage culture to obtain a PHB production of 98% at 30 h.

Key points

• Polyhydroxybutyrate production was studied in a 5-l stirred-tank bioreactor using HPLC

• Mathematical model-assisted fed-batch strategy was implemented in bioreactor

• Two-stage fed-batch cultivation was implemented and PHB production was 93% of dry weight in Gram-positive bacteria

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
EUR 32.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or Ebook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5

Similar content being viewed by others

Data availability

All the data generated or analyzed during this study are included in this article.

References 

Download references

Acknowledgements

One of the authors (JY) thanks the Ministry of Education, New Delhi (India) for providing a senior research fellowship for this research work. The authors thank Dr. R. Jayabalan for his help in the HPLC analysis of PHB.

Funding

The financial support for the study was by ECRA, SERB (Government of India) (Sanction number: ECR/2017/001113).

Author information

Authors and Affiliations

Authors

Contributions

The experimental work of this research has been performed by JY. Modeling and simulation part was done by NP. This research work has been completed under the supervision of NP.

Corresponding author

Correspondence to Nivedita Patra.

Ethics declarations

Ethics approval

This article does not contain any studies with human participates or animals performed by any of the authors.

Conflict of interest

The authors declare no competing interests.

Additional information

Publisher's note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Yadav, J., Patra, N. Modeling of poly-β-hydroxybutyrate production by Bacillus subtilis and its use for feed-forward bioreactor studies. Appl Microbiol Biotechnol 107, 57–69 (2023). https://doi.org/10.1007/s00253-022-12266-6

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00253-022-12266-6

Keywords

Navigation