Department of Microbiology, Dr. MGR-JANAKI College of Arts & Science for Women, Tamil Nadu, Chennai, 600 028, India.
Centre for Drug Discovery and Development, Sathyabama Institute of Science and Technology, Tamil Nadu, Chennai, 600119, India.
Curr Microbiol. 2022 Aug 29;79(10):303. doi: 10.1007/s00284-022-02996-1.
Printed Circuit Board (PCB) includes precious metals, heavy metals and brominated flame retardants. The usage of PCB is increasing exponentially, generated in vast quantities, and considered an E-waste contaminating the environment. The bioleaching potential of a novel isolated Streptomyces BBA4 strain from a coal mine soil was studied and discussed here. A total of twelve isolates were isolated from coal mine soil (Neyveli area). The metal-resistant activity of the isolated cultures was examined using a dot plot and agar well diffusion assay. Both assays revealed that the isolate BBA4 showed resistance and survival ability in the copper (Cu) and chromium (Cr)-rich environment up to 1000 mg/kg and in the iron (Fe) and silver (Ag)-rich environment up to 500 mg/kg, respectively. Based on the phenotypic, physiological, biochemical and molecular characteristics, the novel and potential strain (BBA4) isolated from coal mine soil matched with Streptomyces avermitilis. The strain showed bioleaching ability to recover 73.3% Cobalt and 36.4% Chromium within 120 h under pH 5 (in vitro conditions) from the PCB. The heavy metal content in the PCB was analyzed using quantitative analytical techniques, such as Atomic Absorption Spectroscopy (AAS) and Powder X-ray diffraction (XRD). The analysis of XRD peaks exhibited an increase in crystallinity with the Cr, associated with the accumulation of Cr in the bioleached residues. Thus, generated data from this investigation reveal that BBA4 is an effective bioleaching strain on PCB over other environmentally hazardous chemical leaching methods.
印刷电路板（PCB）含有贵金属、重金属和溴化阻燃剂。PCB 的使用呈指数级增长，产生了大量的 PCB，被认为是污染环境的电子废物。本文研究并讨论了一种从煤矿土壤中分离得到的新型链霉菌 BBA4 菌株的生物浸出潜力。从煤矿土壤（内维利地区）中分离出了 12 株分离株。通过点图和琼脂井扩散试验检测了分离培养物的金属抗性活性。两种试验均表明，分离株 BBA4 显示出在铜（Cu）和铬（Cr）丰富环境中（高达 1000mg/kg）和在铁（Fe）和银（Ag）丰富环境中（高达 500mg/kg）的抗性和生存能力。根据表型、生理、生化和分子特征，从煤矿土壤中分离出的新型潜在菌株（BBA4）与链霉菌avermitilis 相匹配。该菌株在 pH5（体外条件）下，在 120 小时内从 PCB 中回收了 73.3%的钴和 36.4%的铬，具有生物浸出能力。使用原子吸收光谱（AAS）和粉末 X 射线衍射（XRD）等定量分析技术分析 PCB 中的重金属含量。XRD 峰分析表明，随着 Cr 的积累，Cr 的结晶度增加，与 Cr 在生物浸出残渣中的积累有关。因此，这项研究的数据表明，BBA4 是一种有效的 PCB 生物浸出菌株，优于其他环境危害化学浸出方法。
