Establishment of Technology for Microbial Accumulation of Rare Earth Elements.

建立了稀土富集菌的筛选体系。分离到能在Al/100稀释营养琼脂上生长的寡营养细菌。每个分离物在含有稀释营养肉汤的Y(Y，5ppm)中培养。经鉴定，菌株B、D为嗜酸嗜酸单胞菌，菌株F为反常变色杆菌。不同菌株对稀土元素的富集谱不同。稀土元素的积累方式有两种模式。一种是从La到ND的富集菌，另一种是除上述元素外还富集Tb、Dy、Ho和Er的细菌。共获得5株放线菌，其中3株为放线菌。菌株3-1对Yb有特异的积累作用，适用于稀土元素的积累、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.