Detection of Non-Typhoidal Salmonella Using a Mechanism for Controlling Hydrogen Sulfide Production

To know the relation between NaCl concentration and hydrogen sulfide (H2S) production by MY Phenomenon of Salmonella, we developed a method to control H2S production by Salmonella in this study. Desoxycholate-hydrogen sulfide-lactose (DHL) agar was used as the selective medium for Salmonella. Triple sugar iron (TSI) agar was used as the screening medium. Citric acid disks were placed on DHL agar. NaCl was added to both media. After 24 hours incubation, H2S production on DHL agar was stimulated by citric acid, whereas production was suppressed by adding NaCl. The color change in the bottom of the TSI medium was due to the low production of black FeS. The production of FeS was reduced by lower H2S production by Salmonella with an increasing concentration of NaCl from 0.5% to 3%. The inhibition of the black color meant that the color change due to glucose fermentation could be seen clearly in the bottom of the agar. The current method cannot detect glucose fermentation but the addition of more NaCl to the TSI medium allowed the visualization of glucose fermentation by Salmonella. Although H2S production of salmonella was promoted by citrate etc., being controlled by sodium chloride was proved in this study. Thus, we had developed a possibility of novel technique for the detection of Salmonella etc.