Recovery of Manganese from Mine Drainage using Biomineralization

从北海道南部的泉水中分离得到的锰氧化真菌和锰氧化细菌盘状纤丝菌（Leptothrix discophora）（ATCC 43162和51168）被应用于从中性pH的溶液中去除Mn（II）离子。采用XRD、XRF、XPS和FE-SEM等方法对锰沉积物进行了表征。discophora（ATCC 51168），氧化24 ppm的Mn（II）离子，并且细菌在静态培养中保持比在振荡培养中更高的锰氧化活性，这是因为保持了细菌中的鞘结构。建立的培养基组成的ATCC细菌不能直接应用于锰（II）离子的氧化分离的真菌，因此，修改。通过将培养基中有机碳源的浓度降低1/10，真菌在一周内氧化以从溶液中除去超过50 ppm的Mn（II）离子。经鉴定，该真菌为茎点霉属（Phoma sp.）。该真菌可在其体内富集氧化锰沉积物中的细小颗粒。

Manganese-oxidizing fungus, isolated from spring in south of Hokkaido, and manganese-oxidizing bacteria Leptothrix discophora (ATCC 43162 and 51168) were applied to removal of Mn(II) ions from solutions at neutral pHs. The manganese deposits were characterized by XRD, XRF, XPS and FE-SEM.It was found that manganese-oxidizing bacteria, L. discophora (ATCC 51168), oxidized 24 ppm of Mn(II) ions, and that the bacteria kept higher manganese-oxidizing activity in static culture than in shaking culture, because of keeping the sheath structure in the bacteria. The established medium compositions for the ATCC bacteria could not be directly applied to the oxidation of Mn(II) ions for the isolated fungus, therefore, modified. By reduction of 1/10 in concentrations of organic carbon sources in the medium, the fungus oxidized to remove over 50 ppm of Mn(II) ions from the solutions within one week. The fungus was identified to be Phoma sp. The fungus was useful to accumulate fine particles of the oxidized Mn sediments within itself.The bio-mineralized sediments were characterized to be non-crystalline Mn oxides by XRD, XRF, and XPS.