Uranium mining effluents: What about the re-use of mining wastes to improve the bioproduction of industrially relevant bioactive compounds?

ABSTRACT

The shift towards a circular economy, where waste generation is minimized through waste re-use and the development of valorization strategies, is crucial for the establishment of a low carbon, sustainable, and resource-efficient economy. However, there is a lack of strategies for re-using and valorizing specific types of waste, particularly those containing naturally occurring radioactive materials (NORM), despite the prevalence of industrial activities that produce such waste due to their chemical and radiological hazards. Living organisms, including fungi, are valuable sources of bioactive compounds with various industrial applications. In this study, we assessed the growth and metabolic profile changes of three white rot fungi species in response to low concentrations of a uranium mine effluent containing NORM and metals to explore their potential for producing biotechnologically relevant bioactive compounds. The growth rate was assessed in three different culture media, with and without the uranium mine effluent (1% V/V)), and the metabolic profile was analyzed using FTIR-ATR spectroscopy. Results suggested an improvement in growth rates in media containing the uranium mine effluent, although not statistically significant. T. versicolor showed promise in terms of bioactive compound production. The production of droplets during growth experiments and significant metabolic changes, associated with the production of bioactive compounds like laccase, melanin, and oxalic acid, were observed in T. versicolor grown in mYEPDA with the uranium mine effluent. These findings present new research opportunities for utilizing waste to enhance the biotechnological production of industrially relevant bioactive compounds and promote the development of circular economy strategies for re-using and valorizing NORM-containing waste.