Inhibitory Effect of Calcium Peroxide on the Growth of Clostridium, Anaerobic Soil Bacteria

Abstract

Effects of calcium peroxide on the growth of anaerobic bacteria were investigated in terms of preventing fresh-water contamination by Clostridium. Calper^® powder (35% CaO₂), a plant-growth regulator which produces oxygen gradually in soil, was used as the sourse of calcium peroxide. Filtrate of marsh sediments and the filtrate enriched with EG broth (an anaerobes-growth medium) were prepared as the media for the anaerobic bacteria tested. The number of Clostridium butyricum significantly decreased in inverse relation to the increase of oxidation-reduction potentials (ORP) in both media by the addition of calcium peroxide. The growth of Corynebacterium was also inhibited by the addition of calcium peroxide, but the number of Corynebacterium was larger in the EG broth than in the filtrate of marsh sediments. These results suggest that calcium peroxide inhibits the growth of anaerobic bacteria with an increase of ORP, and the effect is influenced by the amount of organic matter in a medium.