Introduction
Usages:
For isolating lactose-fermenting Gram-negative enteric bacilli.
Principle:
Peptones are sources of nitrogen and other nutrients. Lactose is a fermentable carbohydrate. When lactose is fermented, alocal pH drop around the colony causes a color change in the pH indicator (neutral red) and bile precipitation. Bile salts,bile salts no. 3, oxgall and crystal violet are selective agents that inhibit growth of gram-positive organisms. Agar is the solidifying agent.
Formulation（per liter）:
| Pancreatic Digest of Gelatin | 17.0 g |
| Peptones (meat and casein) | 3.0 g |
| Lactose Monohydrate | 10.0 g |
| Sodium Chloride | 5.0 g |
| Bile Salts | 1.5 g |
| Agar | 13.5 g |
| Neutral Red | 30.0 mg |
| Crystal Violet | 1 mg |
| Final pH | 7.1±0.2 |
How to use：
1.Suspend 50 g in 1 L of distilled or deionized water. Heat to boiling to dissolve completely. Autoclave at 121°C for 15 minutes.
2.Transfer 1 mL of Soybean–Casein Digest Broth to 100 mL of MacConkey Broth, and incubate at 42 to 44 for 24 to 48 hours. Subculture on a plate of MacConkey Agar at 30 to 35 deg.C for 18 to 72 hours.
Quality control：
| Item | The name and number of strain | PR/G | Reaction |
| Growth rate | E.Coli ATCC8739 | PR≥0.7 | Rose-red |
| Characteristic difference | Proteus mirabilis CMCC(b)49005 | PR≥0.7 | Colorless, no swarming |
| Selective | Staphylococcus aureus ATCC6538 | G≤1 | － |
Storage: Keep container tightly closed, store in a cool, dry place, away from bright light. Storage period of three years.
Specifications: 250g/bottle
