Effect of an Antibacterial Factor Derived from Bacillus subtilis FHC 402 on the Growth of Bacteria and Mouse Myeloma MPC-11 Cells

The antibacterial activities of Bacillus subtilis FHC 402-derived antibacterial factor (BAF) and hexametaphosphate (HP) and the combined effects of BAF and HP were examined on the growth of 15 strains of bacteria causing food poisoning and spoilage. BAF was more effective on gram-negative bacteria than gram-positive ones. BAF inhibited the cell growth of L. heterohiochii, C. jejuni, V. parahaemolyticus, V. anguillarum and S. typhimurium in the concentration range from 100 to 800 unit/ml. The cell growth of bacteria resistant to BAF such as B. subtilis, B. cereus, L. lactis, E. coli and P. fragi was completely inhibited by the combined use of BAF and 0.1% HP. BAF prolonged the lag phase of the growth of E. coli treated with HP, though HP did not affect the growth of cells treated with BAF. These results suggest that the damage induced by HP facilitates the antibacterial action of BAF on E. coli. We also investigated the effects of BAF and/or HP on the growth and viability of mouse myeloma MPC-11 cells as preliminary tests on the toxicity of these substances. BAF inhibited the growth of MPC-11 cells and decreased the cell viability, but these effects were weaker than those of HP, which has relatively low toxicity in mammalia.