CALDO LAURIL SULFATO MERCK 500G, MERCK

LAURYL SULFATE BROTH GRANULADO (LST) MERCK 500GR

Selective culture medium used as a presumptive test for coliform bacteria and for the selective enrichment of coliform organisms in the analysis of water, according to MALLMANN and DARBY (1941).

This medium complies with the APHA Recommendations for Water Examination (1998) and the ISO 5541-2 (1996) for milk and milk products.

Mode of Action
The high nutrient quality and the presence of phosphate buffer in this medium ensure rapid growth and increased gas production of even "slowly lactose-fermenting" colifirm bacteria. Gas formation can be detected by using fermentation tubes. The lauryl sulfate largely inhibits the growth of undesired bacteria.

Typical Composition (g/litre)
Enzimatic digest of animal and plant tissue 20.0; 
lactose 5.0; 
sodium chloride 5.0; 
sodium lauryl sulfate 0.1; 
di-potassium hydrogen phoshate 2.75; 
potassium dihydrogen phosphate 2.75.

Preparation
Suspend 35.6 g/litre or more, dispense into test tubes fitted with DURHAM tubes, autoclave (15 min at 121°C).
pH: 6.8 ± 0.2 at 25 °C.
The prepared broth is clear and yellowish-brown.

Imagem meramente ilustrativa.