Membrane Lauryl Sulphate Broth

Membrane Lauryl Sulphate Broth is used for the enumeration of Escherichia coli and other coliforms found in filter membranes used in water sample testing.

Originally named Membrane Enriched Teepol broth,(1) this recipe was updated when Teepol 610 was removed from the formulation and replaced by sodium lauryl sulphate. (2&3)The peptones, yeast extract and lactose act as carbon, nitrogen and vitamin sources in this medium.

The phenol red is added as a pH indicator to detect the fermentation of lactose to differentiate the coliforms. Sodium lauryl sulphate is an inhibitory agent.References(1) Burman, N. P., 1967. Development of membrane filter techniques. II.

Adaptation to routine and special requirements. Proc. Soc. Wat. Treat. Exam., 16:40(2) Joint Committee of PHLS and the Standing Committee of Analysis. 1980. J. Hyg. Camb., 85:181(3) Stanfield, G. and Irving, T. E., 1981. A suitable replacement for Teepol 610 is the selective isolation of coliforms from marine waters and sewage. Water Research. 15:469-47

Membrane Lauryl Sulphate Broth is used for the enumeration of Escherichia coli and other coliforms found in filter membranes used in water sample testing.

Shelf Life (days): 1095 days

Storage: Once opened keep the powdered medium closed to avoid hydration and use before the expiry date on the label.

Dehydrated Medium Appearance: Fine Powder

Dehydrated Medium Colour: Beige – light rose

Dehydrated PH: 7.4 ± 0.2

Prepared Medium Appearance: Liquid

Prepared Medium Colour: Red

Prepared PH: 7.4 ± 0.2

Formula g/L

Peptones: 39.0

Yeast Extract: 6.0

Lactose: 30.0

Phenol Red: 0.2

Sodium Lauryl Sulphate: 1.0

Total: 76.2