Effect of Natto Bacteria to the Kind of Bacterias Supported on Crystallization-Type Phosphorus Removal Material on Water Purification Ability

Abstract

The authors have developed a water purification material that can remove phosphorus and organic matter by supporting yeast bacteria, lactic acid bacteria, and natto bacteria on gypsum consolidated bodies containing calcium carbonate. However, the effects of each type of bacteria on water purification properties have been still unclear. In this study, we focused on natto bacteria among these bacterias and investigated its effects on phosphorus and organic matter removal properties. Carrying natto bacteria alone does not contribute to organic matter removal, but coexistence with yeast bacteria or lactic acid bacteria was confirmed to be effective in promoting organic matter removal. When these bacterias were supported on a phosphorus removal material, the phosphorus removal ability generally decreased, but for natto bacteria, the decrease in phosphorus removal ability was small. Furthermore, when natto bacteria and yeast bacteria coexisted, an effect of suppressing the decrease in phosphorus removal ability by yeast bacteria was observed, but this effect was not observed with lactic acid bacteria.