Optimizing microbial strain selection for pyrethroid biodegradation in contaminated environments through a TOPSIS-based decision-making system.

Improved and contemporary agriculture relies heavily on pesticides, yet some can be quite persistent and have a stable chemical composition, posing a significant threat to the ecology. Removing harmful effects is upon their degradability. Biodegradation must be emphasized to lower pesticide degradation costs, especially in the soil. Here, a decision-making system was used to determine the best microbial strain for the biodegradation of the pyrethroid-contaminated soil. In this system, the criteria chosen as: pH (C1), Temp (C2), RPM (C3), Conc. (C4), Degradation (%) (C5) and Time required for degradation(hrs) (C6); and five alternatives were Bacillus (A1), Acinetobacter (A2), Escherichia (A3), Pseudomonas (A4), and Fusarium (A5). The best alternative was selected by applying the TOPSIS (technique for order performance by similarity to ideal solution) method, which evaluates based on their closeness to the ideal solution and how well they meet specific requirements. Among all the specified criteria, Acinetobacter (A2) was the best and optimal based on the relative closeness value (( R i ∗ ) = 0.740 (A2) > 0.544 (A5) > 0.480 (A1) > 0.403 (A4) > 0.296 (A3)). However, the ranking of the other alternatives is also obtained in the order Fusarium (A5), Bacillus (A1), Pseudomonas (A4), Escherichia (A3). Hence this study suggests Acinetobacter is the best microbial strain for biodegradation of pyrethroids; while least preference should be given to Escherichia. Acinetobacter, versatile metabolic nature with various xenobiotic compounds' degradation ability, is gram-negative, aerobic, coccobacilli, nonmotile, and nonspore forming bacteria. Due to less study about Acinetobacter it is not in that much frame as the other microorganisms. Hence, considering the Acinetobacter strain for the biodegradation study will give more optimal results than the other microbial strains. Novelty of this study, the TOPSIS method is applied first time in selecting the best microbial strain for the biodegradation of pyrethroid-contaminated soil, considering this selection process as multi-criteria decision-making (MCDM) problem.

Modeling and simulation of atrazine biodegradation in bacteria and its effect in other living systems.

Atrazine is the most commonly used herbicide worldwide in the agricultural system. The increased environmental concentration of the atrazine showed the toxic effects on the non-target living species. Biodegradation of the atrazine is possible with the bacterial systems. The present study investigated biodegradation potential of atrazine degrading bacteria and the impact of atrazine on environmental systems. Model of atrazine fate in ecological systems constructed using the cell designer. The used model further analyzed and simulated to know the biochemistry and physiology of the atrazine in different cellular networks. Topological analysis of the atrazine degradation confirmed the 289 nodes and 300 edges. Our results showed that the overall biomagnification of the atrazine in the different environmental systems. Atrazine is showing toxic effects on humans and plants, whereas degraded by the bacterial systems. To date, no one has analyzed the complete degradation and poisonous effects of the atrazine in the environment. Therefore, this study is useful for overall system biology based modeling and simulation analysis of atrazine in living systems.Communicated by Ramaswamy H. Sarma.