Bioscience Evidence 2024, Vol.14, No.4, 143-153 http://bioscipublisher.com/index.php/be 150 6 Applications and Future Prospects 6.1 Industrial applications Microbially produced organic acids have a wide range of applications across various industries, including pharmaceuticals, food, and biofuels. In the pharmaceutical industry, organic acids such as lactic acid and itaconic acid are used as building blocks for the synthesis of various drugs and medical products (Baumschabl et al., 2022). The food industry utilizes organic acids like citric acid and fumaric acid as preservatives, flavor enhancers, and acidulants, contributing to the taste and shelf-life of food products (Lorenzo et al., 2022). Additionally, the biofuel industry benefits from organic acids such as succinic acid, which can be converted into bio-based chemicals and fuels, providing a sustainable alternative to fossil fuels (Liebal et al., 2018; Reddy et al., 2020). The microbial production of these acids offers a more sustainable and environmentally friendly approach compared to traditional chemical synthesis, which relies on depletable petroleum resources and harsh reaction conditions (Li et al., 2021). 6.2 Integration with carbon capture technologies The integration of microbial CO2 fixation with carbon capture and storage (CCS) systems presents a promising approach to mitigate greenhouse gas emissions while producing valuable organic acids. Microbial CO2 fixation pathways, such as the Calvin cycle and the Wood-Ljungdahl pathway, can be harnessed to convert captured CO2 into organic acids, thus providing a dual benefit of carbon sequestration and production of industrially relevant chemicals (Salehizadeh et al., 2020; Wang et al., 2023). This approach can be further enhanced by coupling microbial and electrochemical methods, which have shown potential in producing carboxylic acids and alcohols from CO2 using reducing power provided by electrodes (Vassilev et al., 2018). By integrating these microbial processes with existing CCS infrastructure, it is possible to create a more sustainable and economically viable system for reducing atmospheric CO2 levels while generating valuable products (Chen et al., 2023). 6.3 Future research directions Future research should focus on several key areas to improve the efficiency of microbial CO2 fixation and expand the range of products that can be synthesized. One critical area is the enhancement of carbon fixation enzymes and metabolic pathways to increase the conversion rates and yields of organic acids (Salehizadeh et al., 2020; Wang et al., 2023). Genetic and metabolic engineering strategies can be employed to optimize microbial strains for higher productivity and broader substrate utilization (Reddy et al., 2020; Li et al., 2021). Additionally, exploring the potential of mixed microbial consortia and co-culturing schemes can lead to the discovery of new microbial interactions and pathways that enhance the production of target compounds (Konstantinidi et al., 2023). Another important research direction is the development of advanced bioreactor designs and process optimization techniques to improve the scalability and economic feasibility of microbial CO2 fixation processes (Liebal et al., 2018; Lin, 2024). By addressing these challenges, it will be possible to create more efficient and versatile microbial cell factories capable of producing a wide range of valuable organic acids from CO2. 7 Concluding Remarks Microbial CO2 fixation and its conversion into organic acids have emerged as promising strategies to mitigate greenhouse gas emissions and produce valuable biochemicals. Various natural and synthetic pathways have been identified for microbial CO2 fixation, including the Calvin cycle, the Wood-Ljungdahl pathway, and the 3-hydroxypropionate/4-hydroxybutyrate cycle, among others. Key enzymes such as ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) and formate dehydrogenase play crucial roles in these processes. Microbial electrosynthesis (MES) has also shown potential in converting CO2 into organic acids like acetic and butyric acid, with Clostridium scatologenes and other acetogenic bacteria demonstrating significant efficiency in these conversions. Genetic and metabolic engineering have further enhanced the efficiency of these microbial processes, making them viable for industrial applications. The long-term impact of microbial CO2 fixation technologies could be substantial in reducing global CO2 levels. By leveraging the natural ability of microorganisms to assimilate CO2 and convert it into valuable organic compounds, these technologies offer a sustainable and eco-friendly alternative to traditional CO2 capture methods, which are often cost-inefficient and environmentally hazardous. The integration of microbial CO2 fixation with
RkJQdWJsaXNoZXIy MjQ4ODYzMg==