NAC Broth Medium – Nalidixic Acid Cetrimide Broth for Pseudomonas aeruginosa Enrichment, 250g
Nalidixic Acid Cetrimide Broth (NAC Broth Medium) is a selective enrichment medium designed for the detection and cultivation of Pseudomonas aeruginosa from clinical, environmental, and industrial samples. The formulation contains cetrimide as an inhibitory agent to suppress competing organisms, while nalidixic acid (added separately) enhances selectivity for Pseudomonas growth.
Complete Formula (per liter):
Peptone: 20.0 g
Dipotassium Phosphate (K₂HPO₄): 0.3 g
Magnesium Sulfate (MgSO₄): 0.2 g
Cetrimide (Cetyltrimethylammonium Bromide): 0.2 g
Final pH: 7.4 ± 0.2 (25°C)
⚠ Note: The basal medium does not contain nalidixic acid. For selective enrichment, nalidixic acid solution must be added before use.
Preparation & Instructions:
Weigh 20.7 g of NAC Broth powder.
Suspend in 1 liter distilled or deionized water.
Heat to boiling until completely dissolved.
Dispense into suitable containers and sterilize at 121°C for 15 minutes.
Cool to 50–55°C. Under aseptic conditions, add nalidixic acid solution (1 vial per 100 ml broth).
Mix gently and use for selective enrichment of Pseudomonas aeruginosa.
Packaging & Storage:
250 g per bottle
Shelf life: 3 years
Storage: Keep sealed, in a cool and dry environment at room temperature
