Purpose
It is used for the determination of heat-resistant coliform bacteria in drinking water and source water by membrane filtration method.
Inspection principle
Peptone, multi-peptone and yeast extract powder provide nitrogen sources, vitamins and growth factors; Sodium chloride maintains a balanced osmotic pressure; Lactose is a fermentable sugar. Bile salt No. 3 inhibits Gram-positive bacteria; AGAR is the coagulant of the culture medium. Rose red acid and aniline blue are pH indicators. Fecal coliform bacteria can decompose lactose to produce acid at 44.5℃, reducing the pH of the culture medium. The colonies are bright blue, while those of other intestinal bacteria that do not ferment lactose are colorless, gray or light red.
Usage
Weigh 52 grams of this product, add it to 1000mL of distilled water, heat to boiling until fully dissolved, sterilize, and then cool to about 60℃ to make plates for later use.
Quality control
Prepare the culture medium according to the label usage, inoculate the following quality control strains, and place it in an aerobic culture at 44.5℃ for 24±2 hours.