Applied Microbiology and Biotechnology

, Volume 99, Issue 10, pp 4131–4143 | Cite as

Cellulase recycling in biorefineries—is it possible?

  • Daniel Gomes
  • Ana Cristina Rodrigues
  • Lucília Domingues
  • Miguel Gama
Mini-Review
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Abstract

On a near future, bio-based economy will assume a key role in our lives. Lignocellulosic materials (e.g., agroforestry residues, industrial/solid wastes) represent a cheaper and environmentally friendly option to fossil fuels. Indeed, following suitable processing, they can be metabolized by different microorganisms to produce a wide range of compounds currently obtained by chemical synthesis. However, due to the recalcitrant nature of these materials, they cannot be directly used by microorganisms, the conversion of polysaccharides into simpler sugars being thus required. This conversion, which is usually undertaken enzymatically, represents a significant part on the final cost of the process. This fact has driven intense efforts on the reduction of the enzyme cost following different strategies. Here, we describe the fundamentals of the enzyme recycling technology, more specifically, cellulase recycling. We focus on the main strategies available for the recovery of both the liquid- and solid-bound enzyme fractions and discuss the relevant operational parameters (e.g., composition, temperature, additives, and pH). Although the efforts from the industry and enzyme suppliers are primarily oriented toward the development of enzyme cocktails able to quickly and effectively process biomass, it seems clear by now that enzyme recycling is technically possible.

Keywords

Biorefineries Enzyme recycling Cellulase-substrate interactions Lignocellulosic bioethanol Cellulases cost 
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Notes

Acknowledgments

The authors acknowledge the financial support from FEDER and “Fundação para a Ciência e a Tecnologia” (FCT): GlycoCBMs Project PTDC/AGR-FOR/3090/2012–FCOMP-01-0124-FEDER-027948 and Strategic Project PEst-OE/EQB/LA0023/2013, Project “BioInd-Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028” Co-funded by the Programa Operacional Regional do Norte (ON.2–O Novo Norte), QREN, FEDER and the PhD grant to DG (SFRH/BD/88623/2012) and ACR (SFRH/BD/89547/2012).

Conflict of interest

The authors declare that they have no conflict of interest.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  • Daniel Gomes
    • 1
  • Ana Cristina Rodrigues
    • 1
  • Lucília Domingues
    • 1
  • Miguel Gama
    • 1
  1. 1.CEB–Centre of Biological EngineeringUniversidade do Minho, Campus de GualtarBragaPortugal

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