Science Faculty, Universidad de Santander, Bucaramanga, Santander, Colombia.
School of Agricultural and Veterinarian Sciences, Universidade Estadual Paulista, Jaboticabal, São Paulo, Brazil.
PeerJ. 2022 Aug 9;10:e13801. doi: 10.7717/peerj.13801. eCollection 2022.
Metal solubilization from discarded electrical material and electronic devices (e-waste) using the bioleaching capabilities of bacterial cells is highly effective. However, gaps in understanding about the microbiological processes involved in the bioleaching reaction leads to less efficient metal solubilization in large-scale e-waste processing. In this study, bacterial species belonging to the genera and were used to leach copper and gold from discarded printed circuit boards (PCB). Through modulation of the cell-to-cell communication system in these bacteria, phenotypic traits directly involved in the bioleaching reaction were regulated in order to improve the metal solubilization. Addition of the long chain synthetic autoinducer molecule N-acyl homoserine lactone (AHL) of the quorum sensing pathway to the bioleaching reaction resulted in a significant enhancement of metal extraction from PCB. Factors such as: cell attachment to PCB, biofilm formation and hydrogen cyanide (HCN) production were regulated by the quorum sensing system and could be directly related to the improvement of metal bioleaching. Bioleaching reactions using bacterial quorum sensing modulation could represent a valuable tool in overcoming limitations at the industrial level imposed by microbiological traits that lead to inefficient metal bioleaching from e-waste.
利用细菌细胞的生物浸出能力从废弃的电气材料和电子设备（电子垃圾）中溶解金属是非常有效的。然而，由于对生物浸出反应中涉及的微生物过程缺乏了解，导致在大规模电子垃圾处理中金属的溶解效率较低。在这项研究中，使用属于 和 属的细菌从废弃的印刷电路板（PCB）中浸出铜和金。通过调节这些细菌中的细胞间通信系统，调节了直接参与生物浸出反应的表型特征，以提高金属的溶解率。向生物浸出反应中添加群体感应途径的长链合成自诱导分子 N-酰基高丝氨酸内酯（AHL），可显著提高从 PCB 中提取金属的能力。群体感应系统可调节细胞对 PCB 的附着、生物膜形成和氢氰酸（HCN）的产生等因素，这可能与金属生物浸出的改善直接相关。利用细菌群体感应调节的生物浸出反应可能成为克服由于微生物特性导致从电子废物中生物浸出金属效率低下的工业限制的有价值的工具。
