Department of Biochemistry, University of Calcutta, 35 Ballygunge Circular Road, Kolkata, 700019, India.
Department of Food Technology and Biochemical Engineering, Jadavpur University, 188, Raja S.C. Mallick Road, Kolkata, 700032, India.
Sci Rep. 2024 Aug 24;14(1):19707. doi: 10.1038/s41598-024-70658-2.
Synthetic textile dye malachite green (MG) and heavy metals present in industrial wastewater are hazardous to the ecosystem. Bioremediation of dyes and heavy metals using dry-biomasses has advantages over chemical methods. This study screened an acclimatized, heavy metal-resistant, and dye-degrading Gram positive Bacillus licheniformis AG3 strain from the textile wastewater near Kolkata, West Bengal. The EDXRF analysis of this colored wastewater effluent showed 36.33 mg/L lead, significantly higher than the WHO recommendation. Previously, Bag et al. showed bioremediation of synthetic dyes using dry-biomass of Bacillus cereus M from an aqueous solution (Bag et al. Arch Microbiol 203(7):3811-3823, 2021). Here, a consortium of dry-biomasses of B. licheniformis AG3 and B. cereus M strains (1:1 w/w ratio) was prepared for the simultaneous removal of lead and MG from wastewater. Statistical optimization determines that the pH, initial concentration of contaminants, and dry-biomass concentrations are critical for bioremediation under batch procedures. Further, optimization using the response surface methodology showed that 0.01% consortium dry-biomasses eliminated a maximum of 99.35% MG and 96.01% lead (II) within 6 h. SEM-EDS and FTIR confirmed a strong surface biosorption. Furthermore, a fixed-bed biofilter column of the consortium dry-biomasses was prepared, which was able to remove 98.1% MG and 98.5% lead at the 0.5-1 mL/min flow rate. Together, this study developed a biofilter with a consortium dry biomasses of B. licheniformis AG3 and B. cereus M for the simultaneous removal of MG and lead from wastewater.
合成纺织染料孔雀石绿 (MG) 和工业废水中存在的重金属对生态系统是有害的。使用干燥生物量对染料和重金属进行生物修复比化学方法具有优势。本研究从西孟加拉邦加尔各答附近的纺织废水中筛选出一种驯化的、耐重金属和可降解染料的革兰氏阳性地衣芽孢杆菌 AG3 菌株。对这种有色废水的 EDXRF 分析表明，铅含量为 36.33 毫克/升，明显高于世界卫生组织的建议值。此前，Bag 等人曾展示过使用来自水溶液的蜡状芽孢杆菌 M 的干燥生物量对合成染料进行生物修复（Bag 等人，《Arch Microbiol》203(7):3811-3823, 2021）。在这里，制备了地衣芽孢杆菌 AG3 和蜡状芽孢杆菌 M 菌株的干燥生物量混合物（1:1w/w 比），用于同时从废水中去除铅和 MG。统计优化确定，在批处理程序中，pH 值、污染物初始浓度和干燥生物量浓度是生物修复的关键。进一步使用响应面法进行优化，结果表明，0.01%的混合物干燥生物量在 6 小时内最大程度地去除了 99.35%的 MG 和 96.01%的铅（II）。SEM-EDS 和 FTIR 证实了强烈的表面生物吸附。此外，还制备了混合物干燥生物量的固定床生物滤池柱，在 0.5-1ml/min 的流速下，可去除 98.1%的 MG 和 98.5%的铅。总之，本研究开发了一种使用地衣芽孢杆菌 AG3 和蜡状芽孢杆菌 M 混合物的生物滤池，用于同时从废水中去除 MG 和铅。
