Energy consumption by in vitro fungal decolorization of synthetic colorants and an industrial effluent

Abstract

The present study evaluated the decolourisation capacity of four native fungal strains on synthetic dyes and assessed the biotechnological potential of the selected strains in the decolourisation of a real industrial effluent. Discolouration assays were performed on solid medium using six dyes, and the production profiles of laccase, lignin peroxidase, and manganese peroxidase were determined in liquid cultures. Laccase was the most abundantly produced enzyme in all strains. Based on decolourisation potential and enzymatic production curves, Trametes maxima CU1 and Trametes hirsuta CS5 were selected. Eighteen-day-old culture supernatants were used for the decolourisation of Reactive Blue 19 (RB19), Reactive Black 5 (RB5), Crystal Voilet (CV), and the industrial effluent. T. maxima CU1 showed the highest discolouration percentages of synthetic dyes, reaching 97% in AR19 and 61% in RB5 at six hours, while CS5 required nine hours for 41% and 25%, respectively. For CV, CU1 reached 50% at 48 h, and CS5 only 6%. In the industrial effluent, CS5 achieved > 50% discolouration at 293 nm at six hours. CU1 and T. versicolor UAMH 8272 reached 21% and 17%, respectively. At 613 nm, CU1 showed the highest activity (60% at six hours). The process consumed 10,869.43 MJ, the electricity accounting for 76.13% of total energy use. These results confirm T. maxima CU1 high efficiency, highlighting the need to optimize energy consumption for sustainable applications.