Studies of Collagen Binding with Immobilized Salmonella enteritidis and Inhibition with Synthetic and Naturally Occurring Food Additives by a Surface Plasmon Resonance Biosensor

The binding interaction of Salmonella enteritidis with collagen was investigated using the surface plasmon (SPR) biosensor. Collagen I bound to S. enteritidis immobilized on the sensor surface. The mixture of collagen I and laminin generated a synergistic response in the binding interaction with S. enteritidis. Escherichia coli IFO 3301, pathogenic E. coli O157:H7, S. aureus IFO 3060 and 14 strains of Salmonella were immobilized on the gold surface of the sensor chip with different generated refractive index (RI) units. The treatment of S. enteritidis on the sensor surface with hexametaphosphate, citrate, mannose and alginate showed no inhibitory effect on the subsequent binding interaction of collagen I with S. enteritidis. On the other hand, the pretreatment of S. enteritidis with monoglycerol monocaprylate, monocaprate, monolaurate and monomyristate did not show significant effects on the binding interaction of collagen with S. enteritidis; however, the RI unit was largely decreased by the subsequent treatment with the same monoglycerol esters. After treatment of S. enteritidis immobilized on the sensor with natural colors such as San-red MR, San-red YM, San-yellow No.3L, Purple corn extract, Annatto AN and Curcumin "San-Ei," the collagen I binding with bacterial cells was strongly inhibited. When the mixture of additive and collagen was injected, the RI value was lower in the presence of hexametaphosphate, citrate, mannose, alginate, monoglycerol fatty acid esters, diglycerol monomyristate, Japanese horseradish extract, chili extract, peach extract, concentrated tomato juice, San-red MR, San-red YM, San-yellow No. 3L, and Annatto AN than that of the control.