Affiliations: Institute for Chemical Research, Kyoto University,
Uji, Kyoto 611-0011, Japan | Department of Environmental Engineering, Osaka
University, Suita, Osaka 565-0871, Japan
Note: [] Institute for Chemical Research, Kyoto University, Uji, Kyoto
611-0011, Japan. Tel.: +81 774 38 3240; Fax: +81 774 38 3248; E-mail:
esaki@scl.kyoto-u.ac.jp; mihara@mbc.kuicr.kyoto-u.ac.jp
Abstract: In order to develop a biological process for removal of selenium
from industrial wastewater, {\it Bacillus} sp. strain SF-1 was isolated from
selenium-contaminated sediment. The bacterium reduces selenate to selenite and
subsequently to nontoxic insoluble elemental selenium using lactate as an
electron donor and selenate as an electron acceptor in an anaerobic condition.
Elemental selenium transformed from soluble selenium was deposited both inside
and outside of the cells. Since the selenate reduction rate of the strain SF-1
was higher than the selenite reduction rate, selenite was transiently
accumulated. In an experiment of the repeated soluble selenium reduction by
strain SF-1, 0.5 mM of selenate was sequentially treatable with a cycle of one
day. Thus, our sequential system for removal of soluble selenium is very
useful.
