umu logotyp ENLTU eng blue slu logo rgb web RISE logo

ShaojunXiong AnnaStrom2020Shaojun Xiong leads a project on developing joint mushroom and biofuel production, funded by the Swedish platforms BioInnovation and Bio4Energy. Photo by Anna Strom©2020. A highly original research project—on developing joint production of edible mushroom and biofuel—is receiving attention as a top-of-the-line innovation effort in Sweden, as part of the country's aim to develop new technologies and processes for a circular bioeconomy.

A Bio4Energy researcher at the Swedish University of Agricultural Sciences invented the concept, which rests on the idea that both production strands would be more cost effective and environmentally friendly if they were made in synergy.

If this turns out to be the case—if and when the proposed process and the technologies it relies on have been proven—Sweden could become a net producer of edible mushroom and rely less on imports, all the while making cost-competitive ethanol biofuel.

The Swedish national innovation platform BioInnovation funds a part of the project called Comush, which runs from autumn 2017 until autumn 2020. It sorts under the heading BioEconomy 2.0, Better Valorisation of Residual Streams.

The research concept entails growing fungi such as shiitake or oyster mushrooms on wood or forestry residue. The mushroom will break down the polymer lignin in the wood so that another main polymer—cellulose—may be separated out and turned into bioethanol, in an ulterior step.

A main achievement by the Comush project has been to find a way to cleanse the wood of impurities before the start of fungal growth, which is less costly and required less energy than outright sterilisation. Instead, the wood is pre-treated with hot air in a closed chamber, in a procedure tantamount to pasteurisation. Such cleansing is necessary to allow the mushroom to grow without being crowded out by other organisms on the wood surface. 

In a more recent step of the research project, its leader This email address is being protected from spambots. You need JavaScript enabled to view it.; together with Bio4Energy scientists This email address is being protected from spambots. You need JavaScript enabled to view it. and Leif Jönsson of Umeå University; have optimised the preconditions for obtaining a high yield of biofuel.

“We have at this time a way to maximise lignin degradation, but minimising cellulose breakdown”, Xiong said. 

It was a research "breakthrough", according to Xiong, described in a scientific article about to be published.

While it is not yet clear just how effective the new combined process will be when fully developed, Xiong said that "it should be competitive with biofuel technologies on the market". A company called BioSteam is the main industrial project partner and will own the patents in the process of being granted.

Money granted by Bio4Energy, under its Strategic Funds, will allow the research groups of Xiong and This email address is being protected from spambots. You need JavaScript enabled to view it. to investigate whether softwood species such as spruce or pine are equally suitable growing grounds for the fungi as the hardwood birch used in Comush.

“We are working together with several industrial partners and applying for funds from Jordbruksverket (the Swedish Board of Agriculture) and from other sources to be able to further develop the processes and technologies for harvest, pasteurisation and industrial processing. After that we hope to be going onto [large-scale industrial] demonstration trials”, according to Xiong.

Relevant scientific articles (more will be added as they are published)
Chen F, Xiong Sh, Gandla ML, Stagge S, Martín C. 2021. Spent mushroom substrates for ethanol production – effect of chemical and structural factors on enzymatic saccharification and ethanolic fermentation of Lentinula edodes-pretreated hardwoodBioresource Technology 126381. 20 November

Integrated production of edible mushroom (Auricularia auricular-judae), fermentable sugar and solid biofuelRenewable Energy 170, 172-180. June

Grimm A, Eilertsen L, Chen F et al. 2020. Cultivation of Pleurotus ostreatus Mushroom on Substrates Made of Cellulose Fibre Rejects: Product Quality and Spent Substrate Fuel PropertiesWaste Biomass Valor. 3 December

Enabling efficient bioconversion of birch biomass by Lentinula edodes: regulatory roles of nitrogen and bark additions on mushroom production and cellulose saccharification. Biomass Conv. Bioref. June

Chen F, Xiong Sh, Sundelin J, Martín C, Hultberg M. 2020. Potential for combined production of food and biofuel: Cultivation of Pleurotus pulmonarius on soft- and hardwood sawdusts. Journal of Cleaner Production, 266, 122011. September

Wei M, Xiong Sh, Chen F, Geladi P, Eilertsen L, Myronycheva O, Lestander TA, Thyrel M. 2020. Energy smart hot-air pasteurisation as effective as energy intense autoclaving for fungal preprocessing of lignocellulose feedstock for bioethanol fuel production. Renewable Energy, 155, 237-247. August

Xiong Sh, Martín C, Eilertsen L, Wei M, Myronycheva O, Larsson SH, Lestander TA, Atterhem L, Jönsson LJ. 2019. Energy-efficient substrate pasteurisation for combined production of shiitake mushroom (Lentinula edodes) and bioethanol. Bioresource Technology, 274, 65-72. February

BioInnovations årsrapport 2019, pages 8 and 9

IVA Aktuellt Nr 6, 2019 - Årets bästa forskning och teknik, page 24

Bio4Energy on Twitter