Invited Speakers

 

Dr. Mitsuo Yoshida, Global Environment Department, Japan International Cooperation Agency (JICA), Tokyo, Japan

 

Biography: Dr. Mitsuo Yoshida was acquired his doctorate degree from the Graduate School of Science, Hokkaido University, Sapporo in 1982. He has worked for Japan International Cooperation Agency (JICA) since 1992, and current position is the Senior Advisor of JICA, mainly working for environmental management and waste management projects over the world. He was the visiting professor (Environmental Science and Technology) of the Graduate School of Science and Engineering, Tokyo Institute of Technology from 2008 to 2012, and visiting professor (International Environmental Studies) of the Graduate School of Frontier Science, The University of Tokyo from 2012 to 2017. He is also the Director and CEO of the International Network for Environmental and Humanitarian Cooperation (iNehc), Nonprofit Inc., Tokyo, since 2017.

Prof. Kei Nakagawa, Institute of Integrated Science and Technology, Nagasaki University, Japan

 

Biography: Kei Nakagawa is a Professor of Environmental Groundwater Science with 30 years of research experience. He was first appointed as an Assistant Professor in Soil Science of the Department of Agricultural Chemistry in 1999 at Kyushu University and was promoted to Associate Professor in Water Use Engineering of the Department of Agricultural Engineering in 2002 at Kagoshima University. In April 2011, he was appointed Full Professor of Graduate School of Fisheries and Environmental Sciences of Nagasaki University. His main fields of research interest include reactive transport in groundwater, physical and chemical hydrogeology and heterogeneity, saltwater intrusion and performance evaluation of subsurface dams in coastal aquifers, groundwater modeling, and remediation of contaminated soils and groundwater (phytoremediation and electro-kinetic remediation of heavy metal-contaminated soils). Since being appointment at Nagasaki University in 2011, his main research topic has been nitrate pollution resulting from agricultural activities.

 

Invited Talk: Coprostanol Adsorption in Soil Column Experiments: Implications for Groundwater Contamination

Abstract: Coprostanol, an indicator of fecal contamination by humans and livestock, is often detected in groundwater. Coprostanol has also been proposed for use in identifying the sources of nitrate-nitrogen contamination in groundwater. However, their concentrations differed significantly between groundwater and river water, possibly because of their adsorption in riverbed and riverbank sediments. Although the adsorption characteristics of coprostanol on sand, soil, and sediments have been demonstrated in laboratory experiments, the reaction and transport characteristics of coprostanol during its flow from rivers to groundwater have not been clarified. Therefore, in this study, column experiments were conducted to determine how coprostanol is adsorbed during its flow through the soil. In the experiment, the coprostanol solution was passed through the column for a specified time, the column was disassembled, and the coprostanol adsorbed on the solid phase was eluted every 1 cm and analyzed to determine its distribution in the column. The results revealed strong adsorption near the top of the column. The distribution coefficients obtained from the adsorption experiments were used to predict the concentration distribution in the liquid phase.

 

Dr. Bharat Manna, The University of Auckland, New Zealand

 

Biography: Dr. Bharat Manna earned his Ph.D. in Computational Biology from the Indian Institute of Technology Kharagpur in 2021. Currently a Research Fellow in the Department of Civil and Environmental Engineering at the University of Auckland, New Zealand, he has published 24 peer-reviewed articles with an h-index of 12. His research applies environmental biotechnology to optimize biological nutrient removal systems, focusing on resource recovery while investigating antimicrobial resistance development and pathogen proliferation. Dr. Manna specializes in developing microbial redox-manipulation strategies that enhance nutrient removal and micropollutant degradation while reducing greenhouse gas emissions. His work integrates experimental biotechnology with multi-omics approaches and advanced bioinformatics to address urgent challenges in sustainable wastewater treatment, climate resilience, and antimicrobial resistance evolution.

 

Invited Talk: Harnessing Microbial Redox Responses to Enhance Resource Recovery, Micropollutant Degradation, and Resistance Control in Wastewater Treatment

Abstract: Microbial communities in wastewater treatment systems play a pivotal role in environmental sustainability and public health, largely through their redox-driven metabolism. Our research explores how strategic manipulation of microbial oxidative stress responses can address interconnected global challenges: climate warming, wastewater resource recovery, micropollutant degradation, and antimicrobial resistance. We demonstrate that oxidative stress induced by climate-related warming promotes harmful cyanobacterial blooms and enriches antibiotic resistance genes (ARGs), underscoring a critical link between environmental change and public health risk. Within activated sludge systems, strategic oxygen perturbations have been employed to redirect microbial metabolism toward the production of valuable biochemicals such as fatty acids and amino acids, enhancing the potential for sustainable resource recovery. Multi-omics analyses further reveal that oxidative stress conditions facilitate the co-metabolic degradation of structurally diverse organic micropollutants, supporting a predictive framework that links pollutant structures to microbial enzymatic pathways. At the same time, our findings highlight a paradox within conventional treatment systems: while overall ARG loads are reduced, persistent oxidative stress can promote ARG enrichment and de novo emergence via mechanisms involving DNA damage repair, efflux pump activation, and metabolic reprogramming. Together, this body of work demonstrates the potential of microbial redox manipulation as a holistic strategy for advancing wastewater treatment. By integrating climate resilience, enhanced resource recovery, contaminant removal, and resistance control, it provides a blueprint for more sustainable and health-protective environmental biotechnologies.