caa a22 4500 605501890 CHVBK 20210128100603.0 cr unu---uuuuu 210128e20150201xx s 000 0 eng 10.1007/s00253-014-6070-3 doi (NATIONALLICENCE)springer-10.1007/s00253-014-6070-3 Recovery of rare earth elements from the sulfothermophilic red alga Galdieria sulphuraria using aqueous acid [Elektronische Daten] [Ayumi Minoda, Hitomi Sawada, Sonoe Suzuki, Shin-ichi Miyashita, Kazumi Inagaki, Takaiku Yamamoto, Mikio Tsuzuki] The demand for rare earth elements has increased dramatically in recent years because of their numerous industrial applications, and considerable research efforts have consequently been directed toward recycling these materials. The accumulation of metals in microorganisms is a low-cost and environmentally friendly method for the recovery of metals present in the environment at low levels. Numerous metals, including rare earth elements, can be readily dissolved in aqueous acid, but the efficiency of metal biosorption is usually decreased under the acidic conditions. In this report, we have investigated the use of the sulfothermophilic red alga Galdieria sulphuraria for the recovery of metals, with particular emphasis on the recovery of rare earth metals. Of the five different growth conditions investigated where G. sulphuraria could undergo an adaptation process, Nd(III), Dy(III), and Cu(II) were efficiently recovered from a solution containing a mixture of different metals under semi-anaerobic heterotrophic condition at a pH of 2.5. G. sulphuraria also recovered Nd(III), Dy(III), La(III), and Cu(II) with greater than 90% efficiency at a concentration of 0.5ppm. The efficiency remained unchanged at pH values in the range of 1.5-2.5. Furthermore, at pH values in the range of 1.0-1.5, the lanthanoid ions were collected much more efficiently into the cell fractions than Cu(II) and therefore successfully separated from the Cu(II) dissolved in the aqueous acid. Microscope observation of the cells using alizarin red suggested that the metals were accumulating inside of the cells. Experiments using dead cells suggested that this phenomenon was a biological process involving specific activities within the cells. Springer-Verlag Berlin Heidelberg, 2014 Galdieria sulphuraria nationallicence Metal recovery nationallicence Red algae nationallicence Rare earth elements nationallicence Copper nationallicence Minoda Ayumi Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, 305-8572, Tsukuba, Ibaragi, Japan aut Sawada Hitomi Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, 305-8572, Tsukuba, Ibaragi, Japan aut Suzuki Sonoe Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, 305-8572, Tsukuba, Ibaragi, Japan aut Miyashita Shin-ichi National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, 305-8563, Tsukuba, Ibaraki, Japan aut Inagaki Kazumi National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, 305-8563, Tsukuba, Ibaraki, Japan aut Yamamoto Takaiku Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, 565-0871, Suita, Osaka, Japan aut Tsuzuki Mikio School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, 192-0392, Hachioji, Tokyo, Japan aut Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/3(2015-02-01), 1513-1519 0175-7598 99:3<1513 2015 99 253 https://doi.org/10.1007/s00253-014-6070-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00253-014-6070-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Minoda Ayumi Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, 305-8572, Tsukuba, Ibaragi, Japan aut NATIONALLICENCE 700 1- Sawada Hitomi Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, 305-8572, Tsukuba, Ibaragi, Japan aut NATIONALLICENCE 700 1- Suzuki Sonoe Faculty of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, 305-8572, Tsukuba, Ibaragi, Japan aut NATIONALLICENCE 700 1- Miyashita Shin-ichi National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, 305-8563, Tsukuba, Ibaraki, Japan aut NATIONALLICENCE 700 1- Inagaki Kazumi National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, 305-8563, Tsukuba, Ibaraki, Japan aut NATIONALLICENCE 700 1- Yamamoto Takaiku Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, 565-0871, Suita, Osaka, Japan aut NATIONALLICENCE 700 1- Tsuzuki Mikio School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, 192-0392, Hachioji, Tokyo, Japan aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/3(2015-02-01), 1513-1519 0175-7598 99:3<1513 2015 99 253