Product number: 7245

Lowenstein-Jensen Medium is used with fresh egg and glycerol for the isolation and differentiation of Mycobacterium spp. in a laboratory setting. Lowenstein-Jensen Medium is not intended for use in the diagnosis of disease or other conditions in humans.

The use of egg-based media for primary isolation of mycobacteria have two significant advantages. First, egg-based media support a wide variety of mycobacteria. Second, growth of mycobacteria on egg media can be used for niacin testing. Liquefaction of Lowenstein-Jensen Medium can occur if contaminated with proteolytic organisms.

Lowenstein-Jensen Medium is a modification of Lowenstein Medium, modified by Jensen. Jensen modified the medium by alternating the citrate and phosphate contents, eliminating congo red dye, and increasing malachite green concentration. Lowenstein-Jensen Medium is commonly used in the clinical laboratory to isolate acid fast organisms from sterile and nonsterile sources.

 

Formula Liter
L-Asparagine 3.6 g
Monopotassium Phosphate 2.5 g
Magnesium Sulfate 0.24 g
Sodium Citrate 0.6 g
Malachite Green 0.4 g
Potato Flour 30 g

Final pH: 7.2 ± 0.2 at 25°C
Formula may be adjusted and/or supplemented as required to meet performance specifications.

Supplements

Glycerol, 12 mL
Egg Suspension, 1000 mL

Directions

  1. Dissolve 37.3 g of the medium in 600 mL of purified water containing 12 mL of glycerol.
  2. Heat with frequent agitation to completely dissolve the medium.
  3. Autoclave at 121°C for 15 minutes.
  4. Prepare 1000 mL of a uniform suspension of fresh eggs under aseptic conditions. Avoid whipping air into suspension during the collection and mixing.
  5. Aseptically mix the 1000 mL of egg suspension with 600 mL of the sterile Lowenstein-Jensen Medium cooled to 50 – 60°C, avoiding air bubbles.
  6. Dispense the finished medium into sterile screw-cap test tubes. Place the tubes in a slanted position and heat at 85°C for 45 minutes.

Order Details

Product # Product Description
7245A Lowenstein-Jensen Medium, 500 g
7245T Lowenstein-Jensen Medium, 5 kg
7245C Lowenstein-Jensen Medium, 10 kg

Reference Material

7245 - Lowenstein-Jensen Medium, Product Information Sheet [English] [Portuguese]
7245 - Lowenstein-Jensen Medium, Safety Data Sheet [English]

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