Discoloration of Reactive black 5 by individual and consortium of Rhodotorula mucilaginosa, Galactomyces pseudocandidum and Escherichia coli free and immobilized

Abstract

The textile industry is a generator of high volumes of waste water with a high content of pollutants such as azo dyes, which are recalcitrant and persistent in the environment, these ones have been of interest in the last decades for the entities in charge of the care of the environment. This study evaluated the ability to discolor of reactive black 5 (NR5) by a consortium and the microorganisms that constitute Rhodotorula mucilaginosa, Galactomyces pseudocandidum and Escherichia coli free and immobilized in calcium alginate, coffee husks and bagasse of sugar cane. The results show discoloration was evidenced, where the highest percentage corresponds to G. pseudocandidum (90,05%) and the lowest to R. mucilaginosa (79,31%). When comparing the percentages of discoloration between the free microorganisms and the immobilization matrices, it is observed that the former exhibit the highest percentages of discoloration. In addition, there are no significant differences between using cane bagasse or coffee husks as immobilization matrix.

Comparing biofilm reactors inoculated with Shewanella for decolorization of Reactive Black 5 using different carrier materials

“…[22] Another study isolated a microbial community consisting of A. hydrophila, R. mucilaginosa, G. pseudocandidum, and E. coli from dye wastewater and found that this community achieved a decolorization rate of over 95% for RB5 within 24 hours, with a more stable decolorization effect than a single strain. [23] Compared to single strains, mixed microbial communities had stronger advantages in completely mineralizing azo dyes due to the synergistic effect between different degrading microbial communities, which could better degrade azo dyes. [24,25]…”