A-1 Broth

Principle

A-1 broth is composed of the tryptone, lactose, sodium chloride, salicin and Triton X 100. Tryptone serve as
source of carbon and nitrogen, vitamins and other essential nutrients required for bacterial metabolism.
Lactose and salicin act as energy sources and sodium chloride maintains osmotic equilibrium. Triton 100
acts as a surfactant. The fecal coliforms are indicated by the lactose fermentation and gas production in
inverted Durham’s tube. The density of fecal coliform can be calculated by the standard methods using the
MPN table. A-1 Medium can be used in a single-step procedure for the detection of fecal coliforms in source
water, seawater, treated wastewater and foods.

Use: Recommended for detecting fecal coliforms in water samples, waste water, seawater and foods by
MPN Method.

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