Hektoen Enteric (HE) Agar is a selective and differential medium designed for the isolation and differentiation of pathogenic Gram-negative enteric bacteria, including Salmonella and Shigella species, from clinical, food, and environmental specimens.

The medium utilizes bile salts and dyes to inhibit Gram-positive organisms while allowing enteric pathogens to grow. The inclusion of lactose, sucrose, and salicin helps differentiate non-lactose fermenting pathogens such as Salmonella and Shigella from nonpathogenic coliforms based on colony color and hydrogen sulfide (H₂S) production.

Typical colony characteristics include:

Salmonella spp. — blue-green colonies with black centers (H₂S positive)

Shigella spp. — green colonies without black centers

Coliforms (e.g., E. coli) — orange to salmon-pink colonies due to carbohydrate fermentation

Manufactured using optically clear, heavy-duty polystyrene, these plates provide distortion-free viewing and are engineered with stacking rings for safe, stable storage. The breathable packaging prevents condensation, ensuring media integrity and reliable microbial recovery.

Features and Benefits:
• Selective and differential medium for Salmonella and Shigella spp.
• Distinguishes pathogenic enterics from lactose-fermenting flora
• Ideal for stool, food, and environmental testing
• Heavy-duty, optically clear polystyrene for sharp colony visualization
• Breathable packaging minimizes moisture and maintains quality
• Reliable performance for routine pathogen surveillance and quality control