Using microbes to create a circular carbon bio-economy

Sribas Chowdhury, Adamas University, Kolkata

The problem of carbon emission

The emission of carbon has been a major environmental concern for decades. The carbon footprints left behind after using many of the day-to-day appliances, machines and other commodities have had a huge impact on the environment. With global warming being a raging threat for decades, experts say it is time to reconsider the building pillars of our economy and consumerism. The recently published Intergovernmental Panel on Climate Change report by the United Nations deemed greenhouse gas emissions “choking our planet and putting billions of people at immediate risk”. Global warming has reached the status where it is affecting every region of the world and can cause irreversible changes in the climatic conditions of the planet. This puts sustainability and harmony between nature and people in jeopardy. The report called for immediate actions to help alleviate the problems we are facing, otherwise, the repercussions may be fatal. Fortunately, biology has an eco-friendly answer for this.

Utilising principles of biology in carbon recycling 

About 25% of the greenhouse gas emissions occur from the daily appliances we use. With deforestation rapidly increasing, the level of carbon dioxide supply far outweighs the demand and hence, is contributing more to global warming. Under such circumstances, re-evaluation is needed wherein attempts have to be made to convert carbon dioxide sources into carbon dioxide users. Fortunately, different plastics, chemicals and other relevant products are carbon-based. If we can find a way to source the carbon needed for their manufacture from carbon dioxide emissions rather than fossil fuels, the threat posed by carbon dioxide to the world, especially global temperatures, can be significantly reduced. This is where the role of biology comes in. 

Microbes have been long used to make any environmentally harmful process eco-friendly. In the case of carbon recycling, two such processes can be used and are most popular: Gas Fermentation and Microbial Electrosynthesis.

Gas fermentation

Gas fermentation is a microbial process that is used to convert gaseous carbon like carbon monoxide, carbon dioxide, syngas (hydrogen+ carbon monoxide+ carbon dioxide) and other carbon-based gases into chemicals, fuels and polymers. This process uses microbes like Clostridium and Eubacterium to ferment the gases in anaerobic conditions. These pathogens are collectively known as acetogens. This process, albeit slow and prone to inhibition, offers great potential to convert industrial emissions into commercial products. 

Microbial electrosynthesis

Microbial electrosynthesis is another very interesting technique. It uses microorganisms to reduce carbon dioxide into products relevant to industries. In this process, electrons derived from water are supplied to living microbes like Sporomusa ovata through a cathode. The microbes then utilise these electrons to reduce carbon dioxide. This can help in greatly reducing the carbon dioxide levels in the atmosphere while benefiting the consumers and other relevant industries. 

The idea of a Bioeconomy 

The future possibility of a bio-economy based on carbon recycling indeed looks bright. While the processes being studied are still in their nascent stage and are not used on large scales, they are very promising in giving the assurance of an eco-friendly economy in future. Australia has been doing remarkable projects in this arena. Being the hosts of the world’s largest biohydrogen projects, they are clearly doing a lot in this field. The UN reports said that to reduce the global temperatures by 2°C, carbon emissions have to be controlled and decreased. With the recent innovations and push for bioprocesses in various fields like fuel production and other industries, this vision doesn’t seem very far away. Only through consistent efforts and innovation, can we hope for a greener, more eco-friendly and sustainable future.

Also read: The role of certain RNA Helicases in lymphomagenesis

Source:

Wood, J. C., Grové, J., Marcellin, E., Heffernan, J. K., Hu, S., Yuan, Z., & Virdis, B. (2021). Strategies to improve viability of a circular carbon bioeconomy-A techno-economic review of microbial electrosynthesis and gas fermentation. Water Research, 201, 117306. https://doi.org/10.1016/j.watres.2021.117306

• The Corrosion Prediction from the Corrosion Product Performance
• Nitrogen Resilience in Waterlogged Soybean plants
• Cell Senescence in Type II Diabetes: Therapeutic Potential
• Transgene-Free Canker-Resistant Citrus sinensis with Cas12/RNP
• AI Literacy in Early Childhood Education: Challenges and Opportunities