Inhibition of Adhesion of Several Bacteria onto Microtiter Plate by Selected Food Additives

Abstract

Adhesion inhibitory e#ects of food additives, such as Polylysine (PL) and Whey protein (WP), as well as Sucrose fatty acid ester (SFE) with fatty acid of C8 to C18, Monoglycerin fatty acid ester (MFE) with fatty acid of C8 to C18, Gardenia yellow pigment (GY), Monascus pigment (MP), and Protamine (PT) that had been shown to inhibit adhesion of Salmonella Enteritidis onto microtiter plate, were determined on several bacteria. Among SFE tested, adhesion of S. Typhimurium onto microtiter plate was decreased to less than 50 of the control by SFE with fatty acid of C10, C12, C14, and C16 at 0.05 and that of C18 at 0.01. MFE with fatty acid of C8, C10, C12, C16, C18 also inhibited the adhesion to less than 50 of the control. The adhesion of S. Typhimurium was also almost completely inhibited by PT and PL at 0.01, 0.1 MP, 0.025 WP, and 1 GY. Adhesion of Pseudomonas aeruginosa was decreased to less than 50 of the control by SFE with C8 and C16 fatty acid at 0.05, C12 and C14 at 0.01, 0.1 PT, 0.01 PL, and 0.025 WP, but not by 0.05 MFE tested, 1 GY, and 1 MP. Adhesion of P. fluorescens was almost completely inhibited by SFE with fatty acid of C14, C16, and C18 at 0.05, 0.005, and 0.005, respectively, and 1 GY, 1 MP, 0.1 PT, and 1 PL, but not by MFE and WP even at 0.05 and 0.25, respectively. Adhesion of Listeria monocytogenes was decreased to less than 50 of the control by SFE with fatty acid of C10, C12, C16, and C18 at 0.05 and by MFE with fatty acid of C10, C14, C16, and C18 at 0.05, 0.05, 0.005, and 0.005, respectively. The adhesion decreased to less than 50 of the control by 0.1 MP, 1 PT, and 1 PL, but not by 1 GY and 0.25 WP. Adhesion of Staphylococcus aureus decreased to less than 50 of the control by SFE with fatty acid of C10, C12, C14, C16, and C18 at 0.05, 0.01, 0.005, 0.005, and 0.005, respectively. The adhesion was inhibited by more than 50 by 0.05 MFE with C8 fatty acid and by 0.005 MFE with C10 to C18 fatty acid. GY, MP, PT, PL, and WP decreased the adhesion by more than 50 at 0.1, 0.01, 0.01, 0.01, and 0.025, respectively. It seems to be important to select suitable substances for inhibition of adhesion of each of the bacterial species.