Establishment of Technology for Microbial Accumulation of Rare Earth Elements.

建立了稀土元素富集菌筛选体系。分离出能在1 /100稀释的营养琼脂上生长的寡营养细菌。每个分离体在含有稀释的营养液的钇（Y, 5ppm）中培养。我们得到了7株（A-G）能将Y降低到2.5ppm以下的菌株。菌株B和D鉴定为嗜酸单胞菌，菌株F鉴定为异变单胞菌。各隔离体稀土元素富集谱各不相同。稀土元素的富集方式有两种模式。一种是从La积累到Nd的细菌，另一种是除了上述元素外还积累Tb、Dy、Ho和Er的细菌。接下来，我们筛选了Yb积累菌，并将其作为重稀土的代表。得到5株，其中3株为放线菌。菌株3-1特异性积累Yb。这些隔离剂适用于稀土元素的富集、分离和提纯。

We established the screening system for rare earth elements accumulating bacteria. Oligotrophic bacteria which are able to grow on al/100 diluted nutrient agar were isolated. Each isolant was cultured in yttrium (Y,5 ppm) containing diluted nutrient broth. We obtained 7 strains (A-G) which could decrease Y below 2.5ppm.Strains B and D were identified as Comamonas acidovorans, and strain F was Variovorax paradoxus. The spectra of rare earth element accumulation were diferent each other among these isolants. There are two patterns on the mode of rare earth element accumulation. The one is the bacteria which accumulate from La to Nd, and the other is the bacteria which accumulate Tb, Dy, Ho and Er in addition of the above elements.Next, we screened Yb accumulating bacteria, which was used as a representative of heavy rare earths. We obtained 5 strains, in which 3 strains were actinomycetes. Strain 3-1 accumulated Yb specifically.These isolants are applicable to accumulation, separation and purification of rare earth elements.