Problem
Pesticides are a double-edged sword: on the one hand, they support productivity and quality of agricultural crop systems and, on the other hand, their use has undesirable consequences for human well-being and the environment. Their handling and disposal is currently subjected to a strict EU regulatory framework for reducing associated ecotoxicological and human health risks . Thiabendazole (TBZ), a benzimidazole commonly used protectively against postharvest fungal diseases and as anthelminthic in livestock farming, is highly stable (DT50 in soil of > 1 year ) in the environment without previously known potent biodegraders. TBZ-containing wastewaters produced by fruit-packaging plants should be treated, according to the relevant EC regulation, on site. Despite that there are no methods implemented for the treatment of these effluents leading to their land spreading which result in soil contamination at levels reaching up to 12 mg g-1 soil. Hence there is a need for methods to treat TBZ containing effluents to avert its environmental impact. In this context we have previously isolated the first bacterial consortium able to carry out a complete and rapid degradation of TBZ and foressee their use as microbial inocula in biological wastewater treatment facilities receiving effluents from wastewater treatment plants.
Societal impact
The project is expected to optimize the use of a microbial consortium able to degrade a persistent fungicide like Thiabendazole as inoculum in the implementation of tailored-made biological wastewater treatment units in fruit producing areas in Europe and beyond. This will have a major societal impact since (a) it will avert the environmental impact of a dynamic agro-industrial sector like fruit-packaging industry on the environment and the health of the rural population in the fruit producing areas where fruit packaging plants are located and (b) will create opportunities for environmental engineerign companies to uptake and implement novel technologies based on tailored made microbial inocula lke the one studied in the current project creating new work opportunities and opening new positions of work in the private sector
Aim and Objectives
The project aims to disentagle the interactions between consortium members at both nutritional and metabolic level, identify the transformation pathway of thiabendazole and the key players participating in each reaction (microbial, enzymes) and finally verify the efficacy of the consortium against thiabendazole-containing wastewaters under engineering conditions in bioreactors.
Achieving our aim relies on:
- Assessing the stability/composition of the microbial consortium under different degradation stages and conditions.
- Elucidating the roles of the consortium members concerning TBZ degradation
- Understanding the underlying chemical signalling and horizontal gene transfer interplay during and after TBZ biodegradation
- Identifying and validating the degradation pathway of the currently unknown TBZ biodegradation
- Testing/validating the degradation capacity of heterologously expressed enzymes and/or the microbial consortium members in real-world systems like membrane bioreactors
