Molecular Microbiology Research 2024, Vol.14, No.2, 65-78 http://microbescipublisher.com/index.php/mmr 67 compounds, even at low concentrations, raises considerable toxicological concerns, particularly when these compounds are part of complex mixtures (Schwarzenbach et al., 2006). The complexity of environmental pollution is further highlighted in regions like Africa, where artisanal activities and technical failures at exploration sites have led to significant ecological impacts (Odoh et al., 2019). 3.2 Remediation techniques and limitations Various remediation techniques have been developed to address environmental pollution, including chemical, physical, and biological methods. However, each of these techniques has its limitations. Chemical and physical remediation methods often face challenges related to cost, efficacy, and the production of toxic byproducts, which limit their sustainability (Xiang et al., 2022). In-situ remediation techniques, although preferred for their minimal site disturbance and cost-effectiveness, often struggle with the heterogeneous distribution of contaminants in the subsurface, which can significantly impede their effectiveness (Reddy, 2010). Traditional bioremediation approaches, while environmentally friendly, also have limitations, such as the need for specific microbial interactions and the challenges posed by high concentrations of secondary toxins and nutrient limitations (Mishra et al., 2020). Moreover, the complexity of pollutant composition often necessitates the use of combined remediation techniques to achieve efficient and economical environmental remediation (Ugrina and Jurić, 2023). 3.3 SynComs in addressing challenges Engineered Synthetic Communities (SynComs) offer a promising solution to the challenges faced by traditional remediation techniques. SynComs can be designed to enhance the efficiency of bioremediation by leveraging the synergistic interactions between different microbial species. For example, the integration of biochar, plant growth-promoting bacteria (PGPB), and plants has shown potential in overcoming several barriers to the remediation of organic pollutants in soil, such as the lack of suitable sinks for toxins and nutrient limitations (Xiang et al., 2022). Additionally, advancements in microbial electrochemical technologies have been identified as effective approaches for the remediation of pollutants, providing environmentally sound strategies (Mishra et al., 2020). Myco-remediation, which utilizes fungi for the degradation and removal of pollutants, also presents a green and economical alternative to conventional remediation technologies, with the potential to address a wide range of contaminants, including heavy metals and persistent organic pollutants (Akhtar and Mannan, 2020; Kumar et al., 2021a). The application of SynComs in environmental remediation thus represents a significant opportunity to enhance the sustainability and effectiveness of remediation efforts, addressing the limitations of existing techniques and contributing to the protection of global ecosystems. 4 Mechanisms of SynCom-Based Remediation 4.1 Biological pathways utilized by SynComs for degradation of pollutants SynComs employ a variety of biological pathways to degrade pollutants, including enzymatic degradation, microbial metabolism, and electrochemical processes. Microbial enzymes such as hydrolases, oxidoreductases, dehalogenases, oxygenases, and transferases play a crucial role in breaking down toxic pollutants into non-toxic forms (Saravanan et al., 2021). For instance, the bio-electrokinetic (BIO-EK) remediation process combines microbial metabolism and electrochemical oxidation to degrade pyrene and its intermediate products more efficiently than traditional bioremediation methods (Fan et al, 2021). Additionally, the Fe2 +/O2/Tripolyphosphate system demonstrates how reactive oxygen species (ROS) can be regulated to degrade pollutants like p-nitrophenol through oxidation and reduction pathways (Zhang et al., 2022). 4.2 Genetic engineering approaches to enhance SynCom efficiency Genetic engineering techniques have been developed to enhance the efficiency of SynComs in pollutant degradation. These techniques include the immobilization of enzymes and the modification of microbial strains to increase their degradation capabilities. For example, the construction of a novel AgI/BiSbO4 heterojunction enhances the generation of hydroxyl and superoxide radicals, thereby boosting the degradation of organic pollutants under visible light (Zhao et al., 2022). Similarly, the development of enzyme-releasing self-propelled
RkJQdWJsaXNoZXIy MjQ4ODYzNA==