Eosin Methylene Blue (EMB) agar is a selective and differential medium primarily used to isolate gram-negative bacteria, particularly enteric bacilli. It contains dyes (eosin Y and methylene blue) that inhibit the growth of most gram-positive organisms and allows for differentiation based on lactose fermentation.
Here's how various types of bacteria would typically appear when grown on EMB agar:
1. **Lactose Fermenters (e.g., E. coli)**:
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