Harnessing heavy metal-tolerant bacteria and phytotoxicity assessment for ecofriendly treatment of industrial effluents

This study treated heavy-metal pollution in industrial wastewater by isolating and characterizing heavy metaltolerant bacterial strains for bioremediation of industrial wastewater. The effluent samples were sterilized and aseptically inoculated with isolated heavy metal -tolerant bacteria such as Bacillus lichniformis, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia . The samples were subjected to physicochemical analysis, and titrimetric analysis. Further, Atomic Absorption Spectroscopy (AAS) was used for Heavy metal analysis. Phytotoxic assay was carried out by seed germination tests and pot culture study. Over 96 -hour period, improvement featuring reduced turbidity, a stabilized neutral pH, and a substantial 72% decrease in total solids was observed. The application of the bioremediation techniques using heavy metal tolerant bacteria resulted in a significant reduction of heavy metal concentrations, surpassing 85%. Moreover, seed germination rates in the treated industrial effluent were higher than the untreated samples. Pot culture tests further revealed diminished toxicity (2.5%) in treated roots compared to untreated ones (36.7%), accompanied by increased root and shoot growth in the treated pots. The noticeable enhancement in germination rates and the improved growth of plants in the treated effluent underscore the promising potential for the sustainable application of these eco-friendly bacteria, making them a cost-effective microbial bioremediation solution for industrial wastewater.