SUZUKI Yoshihiro




Date of Birth


Research Fields, Keywords


Mail Address

E-mail address

Laboratory Phone number


Laboratory Fax number


Graduating School 【 display / non-display


    Hokkaido University   Faculty of Fisheries   Graduated

Graduate School 【 display / non-display


    Hokkaido University  Graduate School, Division of Fisheries  Doctor's Course  Completed

Degree 【 display / non-display

  • Hokkaido University -  Doctor (Fisheries Science)

  • University of Miyazaki -  Doctor (Engineering)


Papers 【 display / non-display

  • Investigation of <i><b>Escherichia coli</b></i> in Urban Steam with Inflow of Treated Wastewater

    SUZUKI Yoshihiro, NISHIYAMA Masateru, NUKAZAWA Kei, ISHII Satoshi

    Journal of Japan Society on Water Environment   41   19 - 26   2018.03  [Refereed]

    Joint Work

     View Summary

    <p>There is growing concern for the applicability of <i>Escherichia</i> <i>coli</i> as a fecal indicator bacterium in the water environment because <i>E.</i> <i>coli</i> has been reported to regrow in a variety of environments. We investigated longitudinal variation in <i>E.</i> <i>coli</i> counts along a small channel which receives the effluent of treated wastewater. The two fecal indicator bacteria, <i>E.</i> <i>coli</i> and Enterococci, were enumerated, and these bacterial fluxes were calculated from bacteria counts and river flow. As a result, the flux of <i>E.</i> <i>coli</i> was larger downstream of the effluent site than the sum of the fluxes upstream and in the effluent. A high <i>E.</i> <i>coli</i> count was detected in the riverbed sediment of a downstream site. In addition, pulsed-field gel electrophoresis revealed that the genotypes of <i>E.</i> <i>coli</i> isolated from the upstream water, periphyton, and riverbed sediment samples were concordant (similarity = 1.0) . These results indicate that <i>E.</i> <i>coli</i> survived and accumulated in riverbed periphyton and sediment and that <i>E.</i> <i>coli</i> may regrow in a small stream that is strongly affected by treated wastewater. When we assess the fecal pollution in rivers, it is necessary to consider the possibility of <i>E.</i> <i>coli</i> regrowth.</p>

    DOI CiNii

  • Bacterial flora analysis of coliforms in sewage, river water, and ground water using MALDI-TOF mass spectrometry

    Suzuki Y., Niina K., Matsuwaki T., Nukazawa K., Iguchi A.

    Journal of Environmental Science and Health - Part A Toxic/Hazardous Substances and Environmental Engineering   53   160 - 173   2018.01  [Refereed]

    Joint Work

     View Summary

    © 2018 Taylor & Francis Group, LLC. The aim of this study was to rapidly and effectively analyze coliforms, which are the most fundamental indicators of water quality for fecal pollution, using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Coliform bacteria were isolated from municipal sewage, river water, and groundwater. For each sample, 100 isolates were determined by MALDI-TOF MS. In addition, these same 100 isolates were also identified via 16S rRNA gene sequence analysis. Obtained MALDI-TOF MS data were compared with the 16S rRNA sequencing analysis, and the validity of MALDI-TOF MS for classification of coliform bacteria was examined. The concordance rate of bacterial identification for the 100 isolates obtained by MALDI-TOF MS analysis and 16S rRNA gene sequence analysis for sewage, river water, and ground water were 96%, 74%, and 62% at the genus level, respectively. Among the sewage, river water, and ground water samples, the coliform bacterial flora were distinct. The dominant genus of coliforms in sewage, river water, and groundwater were Klebsiella spp., Enterobacter spp., and Serratia spp., respectively. We determined that MALDI-TOF MS is a rapid and accurate tool that can be used to identify coliforms. Therefore, without using conventional 16S rRNA sequencing, it is possible to rapidly and effectively classify coliforms in water using MALDI-TOF MS.


  • Removal and recovery of heavy metals from industrial wastewater by precipitation and foam separation using lime and casein

    Byambaa M., Dolgor E., Shiomori K., Suzuki Y.

    Journal of Environmental Science and Technology   11   1 - 9   2018.01  [Refereed]

    Joint Work

     View Summary

    © 2018 Maralmaa Byambaa et al. Background and Objective: Even today, a strong need exists for the quick and easy removal and recovery of heavy metals from industrial wastewater at low cost. In this study, recovery of heavy metals from artificial wastewater containing Cr, Cu, Cd, Pb and Mo (each concentration, 10 mg L- 1 ) by precipitation and foam separation using lime and milk casein was investigated. In addition, the performance of foam separation was tested using mining tailing water collected from a mining plant. Materials and Methods: Lime was used as an alkaline agent for heavy-metal precipitation. Milk casein functioned as both a collector and a frother for foam separation. After the precipitation process, casein was added to the precipitated wastewater and foam separation was carried out. The removal efficiencies of heavy metals were determined by inductively plasma spectrometry. Results: Under the optimum alkaline condition at pH 9, where the pH was adjusted by lime addition and a casein dosage of 15 mg L- 1 , 96% of Cr, Cu, Cd and Pb were removed from the wastewater and recovered in the foam, however, Mo remained in the water. When the pH of the treated water was re-adjusted at 5.3 and the water was reprocessed by foam separation, 76% of Mo was removed from the treated water. To demonstrate the effectiveness of the proposed precipitation and foam separation method under actual conditions, it was applied to mining tailing water collected from an ore-mining facility in Mongolia. The removal efficiencies of heavy metals such as Mn, Fe and Cu included in the mining tailing water were greater than 85%. Furthermore, more than 90% of the suspended solids were also removed from the tailing water. Conclusion: The casein enabled the collection and recovery of the precipitation components of heavy metals within a total processing time of 10 min. Precipitation and foam separation using lime and casein is an effective and adaptable method for treating industrial effluents that contain heavy metals.


  • Negligible contribution of reservoir dams to organic and inorganic transport in the lower Mimi River, Japan

    Nukazawa K., Kihara K., Suzuki Y.

    Journal of Hydrology   555   288 - 297   2017.12  [Refereed]

    Joint Work

     View Summary

    © 2017 Elsevier B.V. Rivers fulfill an essential ecological role by forming networks for material transport from upland forests to coastal areas. The way in which dams affect the organic and inorganic cycles in such systems is not well understood. Herein, we investigated the longitudinal profiles of the various components of the water chemistry across three cascade dams in Japan: the Yamasubaru Dam, Saigou Dam, and Ohuchibaru Dam, which are situated along the sediment-productive Mimi River in different flow conditions. We analyzed the following water quality components: suspended solids (SS), turbidity, total iron (TFe), dissolved iron (DFe), total organic carbon (TOC), total nitrogen (TN), total phosphorus (TP), humic substance (HS), and major ionic components (Na + , Mg 2+ , Ca 2+ , Cl − , NO 3− , and SO 4 2− ) in the downstream channels of the three dams during the low–intermediate-flow and high-flow events from 2012 to 2014. We estimated hourly loads of each component using hourly turbidity data and discharge data (i.e., L–Q model) separately, and the results are integrated to estimate the annual fluxes. The annual fluxes between the methods were compared to verify predictability of the conventional L–Q models. Annual flux of TOC, TN, DFe, and HS estimated by the turbidity displayed similar values, whereas the flux of SS, TFe, and TP tended to increase downstream of the dams. Among the dams, estimated flux proportions for TP and TFe were higher during high-flow events (74%–94%). Considering geographic conditions (e.g., absence of major tributary between the dams), the result implies that accumulated TP and TFe in the reservoirs may be flushed and transported downstream with SS over the short height dams during flood events. Assuming this process, the reservoir dams probably make only a fractional contribution to the organic and inorganic transport in the catchment studied. The percent flux errors for SS, TFe, and TP fluxes ranged from −7.2% to −97% (except for the TP flux in 2013), which highlights the risk of underestimating these components when using an L–Q model.


  • Antibiotic resistance profiling and genotyping of vancomycin-resistant enterococci collected from an urban river basin in the provincial city of Miyazaki, Japan

    Nishiyama M, Ogura Y, Hayashi T, Suzuki Y

    Water   9   2017.01  [Refereed]

    Joint Work


display all >>

Books 【 display / non-display

Academic Awards Received 【 display / non-display

  • Environmental Technology/Project Award, Environmental Engineering Forum


Presentations 【 display / non-display

  • A study on removal and recovery of heavy metals from industrial wastewater by precipitation and foam separation

    M. Byambaa, E. Dolgor, K. Shiomori, Y. Suzuki

    日本水環境学会 H29年度九州沖縄支部研究発表会  2018.03  -  2018.03  日本水環境学会九州沖縄支部

  • Recovery of heavy metals from wastewater by precipitation and foam separation using lime and casein

    M. Byambaa, E. Dolgor, Y. Suzuki

    第54回環境工学研究フォーラム  2017.11  -  2017.11  土木学会環境工学委員会

  • Conjugative transfer of sntibiotic resistance from vancomycin- resistance Enterococci to Enterococcus genus in water environment

    Nishiyama M, Suzuki Y

    Water Environment Technology Conference 2016  2016.08  -  2016.08  Japan Society on Water Environment

  • Fate of vancomycin-resistant bacteria and corresponding resistance genes in a sewage treatment plant

    Hashimoto R, Furukawa T, Suzuki Y

    Water Environment Technology Conference 2016  2016.08  -  2016.08  Japan Society on Water Environment

  • Qualitative characterization of coastal sand distribution in Miyazaki Coast along Hyuganada by mineralogical Aanalysis

    Itakiyo T, Suzuki Y

    Water Environment Technology Conference 2016  2016.08  -  2016.08  Japan Society on Water Environment

display all >>