Skip to main content
Log in

Production of humic acids by solid-state fermentation of Trichoderma reesei in raw oil palm empty fruit bunch fibers

  • Original Article
  • Published:
3 Biotech Aims and scope Submit manuscript

Abstract

Humic acids (HA) are organic macromolecules of high structural complexity and are primarily obtained from non-renewable carbon sources such as peat and coal. HA is widely used in agriculture but is known to have therapeutic properties, which are still poorly explored. Previous studies have shown the potential of biotechnological processes in the production of HA in submerged fermentation (SF) and solid-state fermentation (SSF) using pre-treated fibers of oil palm of empty fruit bunch (EFB) for the cultivation of Trichoderma strains. EFB is an agro-industrial residue that is readily available at a low cost. The present study aimed to study the production of HA by Trichoderma reesei in the SSF of raw fibers of EFBs from two different palm oil producers. Profiles of HA production, cellular protein, pH, glucose, moisture, and oxygen transfer were obtained during SSF by EFB with and without lipids, as well as, images by electron microscopy of fibers. Results showed efficient HA production in the raw fibers of the EFBs. HA production followed the cellular protein (6 g HA per 100 g of fibers) evolution of the fermentations in the absence of lipids, while the composition of lipids greatly affected its production. The best HA production (350 mg HA per 100 g of fibers) was obtained from EFB that was richer in lignocellulosics and the residual lipids were similar to the fractions of palm and kernel oils, while EFB with lower lignocellulosic presented a production 110 mg HA per 100 g of fibers.

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

Access this article

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

Similar content being viewed by others

References

Download references

Acknowledgements

The authors are grateful for the support given by School of Chemical Engineering (FEQ/UNICAMP), Agropalma and cooperative of small palm oil producing industries from Muniz Ferreira by supplying of the EFB. This work was supported by the scholarship of the Brazilian National Council for Scientific and Technological Development (CNPq) [Grant number 830535/1999-3].

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Reinaldo Gaspar Bastos.

Ethics declarations

Conflict of interest

The authors have no financial conflicts of interest to declare.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Volpi, M.P.C., Corzo, I.J.M., Bastos, R.G. et al. Production of humic acids by solid-state fermentation of Trichoderma reesei in raw oil palm empty fruit bunch fibers. 3 Biotech 9, 393 (2019). https://doi.org/10.1007/s13205-019-1925-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1007/s13205-019-1925-z

Keywords

Navigation