Enhanced biodegradation of toxic pollutants from paper industry wastewater using Pseudomonas sp. immobilized in composite biocarriers and its toxicity evaluation

The present study focused on the immobilization of Pseudomonas putida strain using polyvinyl alcohol mixed with sodium alginate (PVA-SA) and agar-agar (PVA-AA) for the treatment of paper industry wastewater. The bacterial culture immobilized in PVA-SA polymer efficiently removed BOD5, COD, TKN, and TOC, phenol, lignin and color was 69.6 %, 78.6 %, 81.7 %, and 88.0 %, 98.4 %, 65.6 % and 85.7 %, respectively, with 24.8 IU/mL of Lac activity at 6 days of degradation. While using PVA-AA immobilized bacterium the reduction in pollutants; 61.0 %, BOD5; 75.9 %, COD; 76.5 %, TKN; 86.0 %, TOC; 97.9 %, phenol; 62.3 %, lignin and 89.8 %, color respectively with 18.5 IU/mL Lac activity was observed. The content of heavy metals after treatment with immobilized bacterium was also reduced significantly. FTIR analysis of wastewater samples showed that bacterial culture may degrade toxic aromatic compounds significantly. The toxicity data demonstrated that the paper industry wastewater was phytotoxic and cytotoxic in nature, but after treatment, it was reduced significantly.