Lowenstein Jensen Agar
Lowenstein Jensen Medium, when supplemented with egg and glycerol, is used for the cultivation, isolation, and differentiation of Mycobacterium spp. The original formulation of Lowenstein Jensen media was reported by Lowenstein who incorporated congo red and malachite green to inhibit unwanted bacteria1,2. The present formulation is based upon Jensen's modification which eliminates congo red and uses a moderate concentration of malachite green instead to prevent growth of the majority of contaminants surviving decontamination of the specimen. Malachite green acts as an inhibitory agent toward microorganisms other than mycobacteria3 and also serves as an inhibitor and also as pH indicator. This formulation also encourages the earliest possible growth of mycobacteria. Fresh eggs are added aseptically to this media. During heating, the egg albumin coagulates, thus providing a solid surface for inoculation. Nitrogen, fatty acids, and proteins are supplied by egg and asparagine. Glycerol serves as a carbon source and is favorable to the growth of the human type tubercle bacillus while being unfavorable to the bovine type. Do not add glycerol to the medium if bovine or other glycerophobic strains are to be cultured. Formation of blue zone indicates a decrease in pH by gram-positive contaminants (e.g. Streptococci) and yellow zones of dye destruction by gram-negative bacilli.
|Product Name||Catalog #||Quantity|
|Lowenstein Jensen Agar mono plate, 90 x 15 mm||CL9420P||10/pk|
|Lowenstein Jensen Slant||CL9420S||10/pk|
|Lowenstein Jensen Broth||CL9420B||10/pk|
The following organisms are routinely used for testing for this medium.
|Mycobacterium tuberculosis H3RV, ATCC® 27294||Growth; colonies seen in 2 weeks, mature in 3 weeks|
|Mycobacterium kansasii Group I, ATCC® 12478||Growth; colonies seen in 2 weeks, mature in 3 weeks|
|Mycobacterium scrofulaceum Group II, ATCC® 19981||Growth; colonies seen in 2 weeks, mature in 3 weeks|
|Mycobacterium intracellulare Group III, ATCC® 13950||Growth; colonies seen in 2 weeks, mature in 3 weeks|
|Mycobacterium fortuitum Group IV, ATCC® 6841||Growth; colonies visible in 4 days|
User Quality Control
Check for signs of contamination and deterioration. Users of commercially prepared media may be required to perform quality control testing with at least one known organism to demonstrate growth or a positive reaction; and at least one organism to demonstrate inhibition or a negative reaction (where applicable).
Ingredients g/L(Final pH 7.2 +/- 0.2 at 25°C)
3 total citations
- Lowenstein, E. 1933.Ann. Inst. Pasteur.; 50:161
- Lowenstein, E. 1931.Zentralbl. Bakteriol. Parasetenkd. Infektionskr.; 120:127.
- Jensen, F. 1932.Zentralbl. Bakteriol. Parasetenkd. Infektionskr.; Abt. 1 Orig., 125:222.