Changes in microbial diversity in fed-batch reactor operation with wastewater containing nitroaromatic residues

Area of Science:

• Microbiology
• Environmental Science
• Biotechnology

Background:

• Wastewater from the dye industry poses environmental challenges due to complex pollutants.
• Activated sludge processes in Effluent Treatment Plants (ETPs) are crucial for treating industrial wastewater.
• Understanding microbial community dynamics is key to optimizing bioremediation efficiency.

Purpose of the Study:

• To investigate the bacterial diversity in activated biomass from a dye industry ETP.
• To analyze the impact of acclimatization to nitroaromatic compounds on microbial community structure and function.
• To identify key bacterial groups involved in dye wastewater treatment.

Main Methods:

• Isolation and cultivation of bacteria from activated sludge.
• Phylogenetic analysis using 5'-partial 16S ribosomal DNA (rDNA) sequencing.
• Acclimatization of biomass to nitroaromatic-containing wastewater.

Main Results:

• Proteobacteria (alpha, beta, gamma) and Firmicutes were dominant phyla.
• Five previously unidentified culturable bacteria were isolated.
• Acclimatization led to reduced bacterial genus diversity.
• The degradative capacity of the sludge was significantly enhanced.

Conclusions:

• The activated biomass exhibits adaptability to dye industry wastewater contaminants.
• A reduction in diversity correlates with an increase in specific pollutant degradation capabilities.
• The findings suggest potential for developing specialized microbial consortia for enhanced bioremediation.