Salmonella Shigella Agar (SS Agar) is a dehydrated selective medium formulated for isolation and differentiation of Salmonella and Shigella species. It suppresses Gram-positive bacteria and many competing Gram-negatives, while allowing growth of target pathogens with characteristic colony morphology. The medium is widely used in food, clinical and environmental microbiology for selective detection and presumptive identification of Salmonella and Shigella.
Salmonella Shigella Agar (SS Agar), catalogue No. 1064, is a dehydrated selective culture medium intended for the detection, isolation and presumptive differentiation of Salmonella and Shigella species from food, water and clinical samples. The formulation includes peptones for nutrient supply, bile salts and brilliant green to inhibit Gram-positive bacteria, lactose as fermentable carbohydrate, and neutral red as pH indicator.
After reconstitution and sterilization, the medium is poured into Petri dishes. When inoculated and incubated, lactose-fermenting organisms produce pink to red colonies due to acid production, while non-lactose-fermenters such as Salmonella and Shigella produce colorless colonies. Salmonella colonies may also show black centers due to hydrogen sulfide production when sodium thiosulfate and ferric citrate are present.
Advantages
- Selectively inhibits Gram-positive flora and many non-target organisms, allowing growth of Salmonella and Shigella.
- Facilitates differential colony morphology for presumptive identification.
- Suitable for food, water and clinical microbiology laboratories.
- Clear interpretation of lactose fermentation and H₂S production patterns.
Technical specifications
| Pack size | 500 g |
| Intended use | Selective isolation and presumptive differentiation of Salmonella and Shigella spp. |
| Typical colony morphology | Colorless colonies for non-fermenters; pink/red for lactose fermenters; black centers for H₂S producers. |
| Application industry | Food microbiology, clinical microbiology, environmental testing |
| Storage conditions | Store in a cool, dry place, 2–25 °C, tightly closed. |
| Chemical type | Microbial Culture Media |
| Brand | Condalab |
| Pack size | 500 g |
