Genotoxicity evaluation of paper industry wastewater prior and post-treatment with laccase producing Pseudomonas putida MTCC 7525

Abstract

Paper industry wastewater is considered a severe polluter of the environment because it contains various toxic pollutants that critically impact the aquatic and terrestrial ecosystems. The current study aimed to assess the bioremediation perspective of Pseudomonas putida strain to eliminate the hazardous pollutants of paper industry wastewater. The physico-chemical analysis of the treated wastewater showed that the Pseudomonas putida MTCC 7525, which secreted laccase enzyme, significantly reduced the pollution parameters such as EC, TDS, COD, phenols, TKN, TOC, lignin and color by 69, 87, 68, 97, 75, 85, 57 and 72%, respectively in comparison to the control. The organic pollutants in the wastewater samples were characterized and identified by GC-MS and FTIR analysis, which also showed that most of the toxic compounds were reduced following the bacterial treatment. The toxicity assessment of the wastewater was performed in terms of cyto-genotoxicity and phytotoxicity assay using onion and mung bean plants. The result of the toxicity study demonstrated that the toxic effect of the wastewater samples declined after the bacterial treatment. These results showed that Pseudomonas putida MTCC 7525 could be used effectively in the paper industry for bioremediation applications, thus minimizing the undesirable effects on the environment.