Preservative Effect of Polyphosphates (III) Synergistic Action of Hexametaphosphate and Cholate on Escherichia coli

• Published in: Food Hygiene and Safety Science (Shokuhin Eiseigaku Zasshi) Vol. 19; no. 2; pp. 190 - 194_1
• Main Authors: TUTUMI, Masakazu, YASUI, Kikuyo, MATSUOKA, Asao, WATANABE, Tadao
• Format: Journal Article
• Language: English
• Published: Japanese Society for Food Hygiene and Safety 1978
• ISSN: 0015-6426; 1882-1006
• DOI: 10.3358/shokueishi.19.190

In the preceding paper, we reported that the antibacterial action of hexametaphosphate (HP) was enhanced in the presence of surface-active agents such as cholate (CA) and monocaprin and others. The mode of synergistic action of CA on HP was investigated using Escherichia coli, and some results as given below were obtained. Though the O2-uptake of E. coli could not be inhibited by the addition of CA or HP alone, HP showed the inhibitory effect when CA was added prior to HP. When these drugs were added in reverse order, HP did not inhibit the O2-uptake of E. coli. In addition, HP masked with Calcium ion did not show the inhibitory effect of O2-uptake even if CA was added prior to HP. While HP hardly acted on the spheroplast of E. coli, CA acted vigorously on the spheroplast and accelerated the cell-lysis. As a result of the cell-lysis, the viscosity of the medium rapidly increased. Although CA acted on E. coli and released the substances which show absorbance at 260nm, neither a marked release of the cell components from E. coli nor the cell-lysis of the spheroplast by HP-treatment was observed. From the result of the previous and this paper, one of the mechanism of the synergistic action of CA on the antibacterial action of HP was deduced that CA acts on the cell envelope of E. coli, alters the permeability barrier, continues to keep the state as it is, and the action of HP on E. coli is particularly enhanced under this condition.