Preservative Effect of Polyphosphates (II)

Action of Hexametaphosphate on Escherichia coli

Abstract

Though sodium hexametaphosphate (HP) had little antibacterial activity against Escherichia coli, HP showed the strong antibacterial action on E. coli in the presence of surface-active agents such as cholate (CA), dodecylbenzenesulfonate, sodium dodecylsulfate and monocaprin. HP masked with Ca²⁺ vanished the activity completely in spite of the presence of CA. HP scarcely exhibited the activity against E. coli pretreated with CA. That is, it appears that the combined use of CA and HP is necessary in order to enhance the antibacterial activity of HP against E. coli.
The experiment of preservative effect by the combined use of HP and monocaprin was conducted with raw Japanese noodle. In this experiment it was confirmed that the combined use of them is more effective than the use of HP or monocaprin alone.