Bioremediation of Manganese by Thermophilic Bacterial Isolates of Tapt Kund, Soldhar, and Gauri Kund Hot Springs of Uttarakhand, India

Manganese (Mn) contamination in groundwater is a global concern due to its harmful effects. The high concentration of Mn2+ in humans creates memory issues, decreased fertility, appetite loss, sleeplessness, sperm abnormalities, and ‘Manganism’. In this study, the isolation of thermophiles was followed by their assessment for MIC (minimum inhibitory concentration) and Mn bioremediation. We have isolated a total of 11 Mn-resistant bacterial strains of thermophiles with the identification of their bioremediation potential from the Tapt Kund, Soldhar, and Gauri Kund hot springs of Uttarakhand, India. Out of 11 strains, three isolates (TA8, SA9, and GA7) were identified with the highest metal resistance properties for toxic Mn2+. The metal tolerance capabilities of the strains were evaluated through MIC and the metal biosorption rate was estimated by the live cells bioremediation through thermophilic bacteria. ICP-MS (inductively coupled plasma mass spectrometry) was used to assess the Mn2+ removal rate of bacterial bioremediation. It turned out that every strain exhibited promising bioremediation potential and proved Mn-resistant. The bacterial strain TA8 exhibits the highest MIC (600 µg.L-1.) with a bioremediation rate of 98.34% for Mn2+. The bacterial strain SA9 has a MIC value of 525 µg.L-1, with a biosorption rate of 77.74% for Mn2+. The bacterial strain GA7 has a MIC of 475 µg.L-1, with an efficiency rate of 61.17% for Mn2+ removal. The most promising strain of thermophilic bacteria for Mn2+ bioremediation is the TA8, which has demonstrated the highest potential (98.34%) out of all the tested strains. The findings may have public health implications, as reducing manganese levels in groundwater can help mitigate health risks associated with Mn exposure. Also, this research enriches our knowledge of microbial bioremediation and its potential applications in environmental management. Ultimately, this research could offer a novel, economical, and environmentally beneficial approach to managing metal toxicity