Usages:

For the rapid detection and enumeration of coliform bacteria.

Principle:

Peptone and yeast extract powder provides carbon and nitrogen sources and trace elements; sodium chloride maintains osmotic equilibrium; agar as medium coagulant; dodecyl sulfate inhibit Gram-positive bacteria; chromogenic substrate and large intestine flora β- galactosidase-glucosidase specific reaction, hydrolysis of the substrate, the release of the color groups  produce green colonies on the light yellow plate.

Formulation (per liter):

Peptone :10g

Yeast extract powder: 3g

sodium chloride:5g

sodium lauryl sulfate:0.1g

Agar :12g

Chromogenic substrate 2.7g

Final pH 7.0 ± 0.2

How to use:

1. Weigh 32.8g of this product, adding 1L of distilled or deionized water , heated to boiling stirring until completely dissolved, dispensing into flask without autoclaving.

2,Take 25g or 25mL of sample with aseptic procedures, added to the flask containing 225mL of sterile phosphate buffered saline (or saline) is shaken thoroughly homogenized with a homogenizer or a 1:10 dilution 1min, then 1:10 dilution continue to select the appropriate serial dilutions of three, two plates each dilution was inoculated.

3, the use of pour method: The medium is cooled in a water bath to about 50 , sterilized petri dish having a diameter 90mm, 1ml samples were inoculated per dish, then poured into about 15ml of the above dissolution medium, and mix to solidify, upside down, 37 for 24 hours.

4, using surface inoculation: cooled to about 50 , shake devoted to the medium in sterile petri dish. Can be stored in the refrigerator for a day or stored at room temperature for several days (dark, 4 ). The sample was streaked method or filter method, 37 for 24 hours.

5, observe the results.

Quality control:

This product appear light yellow after pouring into plate, these strains were inoculated after 36 ± 1 18 ~ 24h culture growth in the following table.

Growth of bacteria were cultured bacteria numbers feature

Escherichia coli ATCC25922 good green colonies

Citrobacter ATCC8090 good green colonies

Salmonella typhimurium CMCC50115 good colorless colonies

Enterococcus faecalis ATCC29212 suppressed —–

Storage: Store at 10-30 , dark, cool and dry place, tighten the cap immediately after use. Storage period of two years.