Mining wastes containing appreciable concentrations of silver are considered alternative sources for metal extraction, although these wastes are often refractory due to the presence of manganese oxides. The high cost and/or environmental impact of the hydrometallurgical and pyrometallurgical extraction processes make it necessary to search for biotechnological processes for the solubilization of manganese compounds. This paper describes the characterization of chemoorganotrophic microorganisms indigenous to the tailings of a silver mine located in Coahuila, México, regarding their capability to remove manganese and silver present in these residues by lixiviation. The Bacterial and fungal strains isolated were identified by sequencing the rDNA 16S and ITS-1-ITS-2 genomic regions, respectively; the bacterial strains correspond to isolates of Roseospira sp. and Sphingomonas sp., whereas the fungal strains include isolates of Cladosporium sp. A, Cladosporium sp. B and Penicillium chrysogenum . These fungal strains show an effective capacity to lixiviate manganese and silver from solid mine residue when incubated in 9 k medium; it was found that under these conditions, leaching of metals occurs due to a mixed biotic-abiotic process, which yields manganese and silver leaching efficiencies in the ranges of 58–74% and 40–67%, respectively. The fungal strains grown in the LMM medium and the bacterial strains incubated in the PDB medium caused leaching of manganese with a lower efficiency in the range of 0.17–0.24% and 1.42–1.73%, respectively; under these conditions, silver leaching by fungal and bacterial strains appeared to be reduced (< 0.1%).Through in vitro cultures, it was determined that P. chrysogenum and Sphingomonas sp. showed the highest levels of silver resistance. Graphic abstract

中文翻译：

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使用尾矿中的原生微生物生物浸出锰和银的好氧工艺

含有显着浓度银的采矿废物被认为是金属提取的替代来源，尽管由于锰氧化物的存在，这些废物通常是难熔的。湿法冶金和火法冶金提取工艺的高成本和/或环境影响使得有必要寻找用于溶解锰化合物的生物技术工艺。本文描述了位于墨西哥 Coahuila 的银矿尾矿中固有的化学有机营养微生物的特征，了解它们通过浸出法去除这些残留物中存在的锰和银的能力。分离的细菌和真菌菌株分别通过对 rDNA 16S 和 ITS-1-ITS-2 基因组区域进行测序来鉴定；细菌菌株对应于玫瑰螺菌属的分离株。和鞘氨醇单胞菌属，而真菌菌株包括枝孢菌属的分离株。A，枝孢菌属。B和Penicillium chrysogenum。当在 9k 培养基中培养时，这些真菌菌株显示出从固体矿渣中浸出锰和银的有效能力；研究发现，在这些条件下，金属的浸出是由于混合的生物-非生物过程，其锰和银的浸出效率分别在 58-74% 和 40-67% 的范围内。在 LMM 培养基中生长的真菌菌株和在 PDB 培养基中培养的细菌菌株导致锰的浸出效率较低，分别为 0.17-0.24% 和 1.42-1.73%；在这些条件下，真菌和细菌菌株对银的浸出似乎减少了（< 0.1%）。通过体外培养，确定P. chrysogenum 和Sphingomonas sp。显示出最高水平的银电阻。图形摘要