![Salmonella colonies on DX agar (arrows) salmonella on desoxycholate citrate agar](salmonella enterica 011.jpg)
Primary isolation of Salmonella spp. from stool on desoxycholate-citrate agar.
Black colonies of Salmonella enterica subsp. enterica (lactose-negative, H2S-positive) and pink colonies of Klebsiella pneumoniae (lactose-positive, H2S negative) on desoxycholate-citrate agar. Desoxycholate citrate agar is a moderately selective solid medium used to screen Salmonella spp. and Shigella spp. from clinical specimens. Sodium deoxycholate and sodium citrate in the medium inhibit growth of gram-positive bacteria and many coliforms.