Multiple organic substrates support Mn(II) removal with enrichment of Mn(II)-oxidizing bacteria

Ahmad Shoiful; Taiki Ohta; Hiromi Kambara; Shuji Matsushita; Tomonori Kindaichi; Noriatsu Ozaki; Yoshiteru Aoi; Hiroyuki Imachi; Akiyoshi Ohashi

doi:10.1016/j.jenvman.2019.109771

Multiple organic substrates support Mn(II) removal with enrichment of Mn(II)-oxidizing bacteria

J Environ Manage. 2020 Apr 1:259:109771. doi: 10.1016/j.jenvman.2019.109771. Epub 2019 Dec 4.

Authors

Ahmad Shoiful¹, Taiki Ohta², Hiromi Kambara², Shuji Matsushita³, Tomonori Kindaichi², Noriatsu Ozaki², Yoshiteru Aoi⁴, Hiroyuki Imachi⁵, Akiyoshi Ohashi⁶

Affiliations

¹ Department of Civil and Environmental Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8527, Japan; Center of Technology for the Environment, Agency for the Assessment and Application of Technology (BPPT), Geostech Building, Kawasan PUSPIPTEK, Serpong, Tangerang Selatan, 15314, Indonesia.
² Department of Civil and Environmental Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8527, Japan.
³ Western Region Industrial Research Center, Hiroshima Prefectural Technology Research Institute, 2-10-1, Aga-minami, Kure, Hiroshima, 737-0004, Japan.
⁴ Program of Biotechnology, Graduate School of Integrated Sciences for Life, Hiroshima University, 1-3-1 Kagamiyama, Higashihiroshima, Hiroshima 739-8530, Japan.
⁵ Department of Subsurface Geobiological Analysis and Research (D-SUGAR), Japan Agency for Marine-Earth Science & Technology (JAMSTEC), Yokosuka, Kanagawa, 237-0061, Japan.
⁶ Department of Civil and Environmental Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima, Hiroshima, 739-8527, Japan. Electronic address: ecoakiyo@hiroshima-u.ac.jp.

PMID: 32072950
DOI: 10.1016/j.jenvman.2019.109771

Abstract

Three different organic substrates, K-medium, sterilized activated sludge (SAS), and methanol, were examined for utility as substrates for enriching manganese-oxidizing bacteria (MnOB) in an open bioreactor. The differences in Mn(II) oxidation performance between the substrates were investigated using three down-flow hanging sponge (DHS) reactors continuously treating artificial Mn(II)-containing water over 131 days. The results revealed that all three substrates were useful for enriching MnOB. Surprisingly, we observed only slight differences in Mn(II) removal between the substrates. The highest Mn(II) removal rate for the SAS-supplied reactor was 0.41 kg Mn⋅m^-3⋅d^-1, which was greater than that of K-medium, although the SAS performance was unstable. In contrast, the methanol-supplied reactor had more stable performance and the highest Mn(II) removal rate. We conclude that multiple genera of Comamonas, Pseudomonas, Mycobacterium, Nocardia and Hyphomicrobium play a role in Mn(II) oxidation and that their relative predominance was dependent on the substrate. Moreover, the initial inclusion of abiotic-MnO₂ in the reactors promoted early MnOB enrichment.

Keywords: Biological manganese oxidation; Down-flow hanging sponge reactor; K-medium; Manganese-oxidizing bacteria; Methanol; Sterilized activated sludge.

MeSH terms

Bacteria
Bioreactors
Manganese Compounds*
Oxidation-Reduction
Oxides*

Substances

Manganese Compounds
Oxides