Removal of soil pollutants by following metabolic modelling

Herbicide degradation in crop soils is mainly dependent on the inhabiting microbial communities. The accumulation of these herbicides exerts a negative effect to the ecosystem. The project work is focused on the accelerated degradation of these excess herbicides such as atrazine and diuron by using advanced computational approach. Atrazine biodegradation includes the approach of metabolic modelling of microbial communities. The effects of metabolites (carbon and nitrogen source: mainly amino acids) was investigated on rate of degradation of atrazine in soil. By following constraint based modelling, predictions were done for a range of metabolite and bacterial combinations. The validations were carried out in pot experiments on a reporter plant (wheat). The image processing (green ness of plant) and fresh weight (significant at p<0.05) was kept as bioassay parameter for atrazine degradation in soil. HPLC analysis and amplicon sequencing (16S rRNA gene) is being done to detect the residual atrazine in soil and shifts in microbial communities, respectively. Apart from atrazine, diuron degradation in soils is also being investigated. The significant (p<0.05) diuron degradation in soil was detected through HPLC and shifts in microbial communities (16S rRNA gene) was also observed. In parallel, metabolic model was constructed for the linuron/diuron degrader Variovorax sp. strain SRS16. Simulations ranked metabolites according to their potential to enhance degradation and predictions are being validated in the wet laboratory. To date, predictions for enhance degradation following glutamine amendment was confirmed in-vitro.

The research work is going to be concluded with the development of commercial clean up solutions of crop soils.