The additive free microwave hydrolysis of lignocellulosic biomass for fermentation to high value products

Jiajun Fan, Fabio Santomauro, Vitaliy L. Budarin, Fraeya Whiffin, Felix Abeln, Tanakorn Chantasuban, Deborah Gore-Lloyd, Daniel Henk, Roderick J. Scott, James Clark*, Christopher J. Chuck

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Current biorefineries are predominantly based around single feedstock sources, extensively hydrolysed using multiple unit operations. The hydrolysate is generally converted to a single product by one of a few well-characterised organisms. Here, we report on a new approach to the biorefinery, combining a rapid, microwave heated, one-step depolymerisation process, with a yeast, Metschnikowia pulcherrima which is able to metabolise an array of oligo- and monosaccharides. During the investigation it was found that the microwave hydrolysis process was able to solubilize upto 50% wheat straw biomass by weight, mainly as oligosaccharides though also containing mixtures of pentose, hexose and anhydro-sugars with concentrations of up to 2 g L-1. However, a fine balance between elevated monosaccharide yields and the production of inhibitive compounds had to be struck with optimal microwave hydrolytic conditions found to be 190 °C. Further testing utilizing several different types of lignocellulosic biomass demonstrated it was possible to attain ~65% carbon efficiency in the conversion of Laminaria saccharina to hydrolysis products. The system was scaled to 600 mL using DDGS successfully solubilizing 66% of the feedstock, producing 33 g L-1 hydrolysate. M. pulcherrima grew well on this hydrolysate in a controlled stirred tank bioreactor (2L), yielding 8.38 g L-1 yeast biomass, a yeast biomass coefficient of 0.25. This presents an exciting, feedstock agnostic, pathway to the energy efficient production of a wide variety of commercially valuable chemical products without the need for extensive pre and post processing technologies.

Original languageEnglish
Pages (from-to)776-784
Number of pages9
JournalJournal of Cleaner Production
Early online date11 Jul 2018
Publication statusPublished - 10 Oct 2018


  • Bio-refinery
  • Fermentation
  • Integrated technology
  • Microwave hydrolysis

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