29 April 2019 By Michael Lienemann (Dr. rer. nat.)

Novel gas fermenting organisms for the production of food, feed and chemicals from CO2 and renewableenergy

Why do we need novel means for producing food, feed and chemicals?

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CO2 emissions have to be decreased to net-zero by 2050 in order to limit global temperature rise to +2ºC before post industrial levels

20% of human green house gas emissions originate from food production

Microalgae, such as Spirulina, are an alternative food source that does not require farming and has been used ~ 600 years ago by Aztech tribes (central Mexico)

Bioelectrochemical systems can produce organic carbon from CO2 at an energy efficiency exceeding photosynthesis (i.e., 6.4% vs. 2.9% in microalgae)

Why do we need novel means for producing food, feed and chemicals?

CO2 can be assimilated in bioelectrochemical systems by hydrogen oxidizing bacteria (HOB) on electrolyticallyproduced H2 and O2 [Schlegel et al. 1965 Nature]

HOB can grow to OD’s of 130 (38 g CDW/ l) within 6 days on H2/CO2/O2 gas mixture [Reed J et al. 2017 California Energy Commission Report CEC-500- 2017-005]

Electricity

Air (CO2 + water) Organic

carbon

Anode Cathode

H2O 2 H+

2H+ + O2 H2

CO2

H2O

Minerals

Bioelectrochemical system

CO2 Assimilation by hydrogen oxidizing bacteria

HOB Biomass as a protein source

HOB Microbial protein contains typically 40–65% protein

Comparable or higher than vegetarian protein-rich foods such as soybeans and Quorn

[Sources: - Linder T. 2019 Food Sec. https://doi.org/10.1007/s12571-019-00912-3- Nishinari K et al. 2014 Food Hydrocolloid 39, 301–318]

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Protein content of microbial food products & basic foodstuffs

Leo Ojala

Microbial (HOB) protein produced from electricity and CO2

in a bioelectrochemical system at VTT

Espoo (Finland), 30 August 2018

CO2 Assimilation by hydrogen oxidizing bacteria

Bioelectrochemical system (BES) H2 & O2 produced in situ from H2O (I = 18 mA)

H2 concentration decreases during bacterialgrowth and reaches zero at 12 h C

CO2

O2

H2

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Growth of Cupriavidus necator H16 in BES

e

• Direct air capture of CO2

• Hydrogen production using scalable electrolyzer stack (total

electrode area 380 cm2)

• Operation at cH2 < 4% (Flammabillity limit)

• Bioreactor volume 20 liter under 4 bars of pressure

• Culture liquid circulated at 1 m3/h

• Estimated biomass production rate 4 g/h

Upscaling food production from CO2 and electricity

• Direct air capture of CO2

• Hydrogen production using scalable electrolyzer stack (total

electrode area 380 cm2)

• Operation at cH2 < 4% (Flammabillity limit)

• Bioreactor volume 20 liter under 4 bars of pressure

• Culture liquid circulated at 1 m3/h

• Estimated biomass production rate 4 g/h

Upscaling food production from CO2 and electricity

Acknowledgements

• Prof. Merja Penttilä• Emilia Nordlund (Project management)• Leo Ojala (Cultivations & calculations)• Dilek Ercili-Cura (Food testing)• Mikko Wuokko (Cultivations)• Anu Tamminen (Cultivations)• Peter Blomberg (Analytics)• Petteri Kokkonen (Electrolyzer stack design)• Cyril Bajarmundi (Direct air capture)• Jere Elfving (Direct air capture)• Atte Mikkelson (Gas analytics)• Irina Tsitko (Microbiology)• Hanna-Leena Alakomi (Food safety analysis)

• Prof. Jero Ahola• Vesa Ruuskanen• Georgy Givirovskiy• Jani Sillman

• Juha-Pekka Pitkänen• Pasi Vainikka• Sami Holmström

• Eija Jokitalo• Helena Vihinen• Mervi Vikman