Prof. MATSUURA Norihisa

Faculty of Geosciences and Civil Engineering, Kanazawa University

Title

Microbial Community Analysis of Enhanced Biological Phosphorus Removal Process (EBPR) Associated Sulfur Cycle

Abstract

EBPR process is a biological process to remove phosphorus from wastewater. Studies reported that several factors might affect EBPR performance such as Glycogen Accumulating Bacteria (GAO), pH, nitrate, and Sulfate (SO₄^2-). The presence of SO₄^2- might induce growth of Sulfate Reducing Bacteria (SRB) which produces Sulfide (H₂S/HS⁻) that inhibit different organisms. On the other hand, several studies reported that the presence of SO₄^2- may promote better phosphorus removal. Thus, the knowledge of SO₄^2- effect in EBPR system has not been fully understood. The poupous of this study is to elucidate the effect of the sulfur cycle in the EBPR process. Two EBPR reactors were operated under different sulfate concentrations. And microbial community based on 16S rRNA gene was analyzed to identify the key microbes. Two laboratory-scale SBRs were operated with different (high and low) sulfate concentrations. The total time to complete one cycle was 8 h, which included a 30-min feeding phase, a 2-h 45-min anaerobic phase, a 3-h aerobic phase, a 1-h settling phase, and a 30-min effluent phase. At the end of reactor operation, sludge samples were taken from both reactors, and DNA was extracted using an DNA extraction kit according to manufacturer instructions. Extracted DNA was analyzed by Illumina MiSeq. In my presentation I will present the results.