Molecular biology media
LB Agar (Lennox)
Recommended medium for maintaining and cultivating recombinant strains of E. coli.
- Cat. No.
- LC-1083
- Category
- Molecular biology media
- Format
- 500 g
- Storage
- 2 to 25 °C
- Minimum guaranteed shelf life
- 15 months
LB Agar (Lennox) is a nutritionally rich medium developed by Lennox for the growth and maintenance of pure cultures of recombinant strains of E. coli used in molecular microbiology procedures.
Key features
Applications
Preparation and recovery of Escherichia coli competent cells.
Industry
Culture media for molecular biology.
Preparation
35 g in one liter of distilled water; boil for one minute, sterilize in autoclave at 121 °C for 15 minutes.
Principles and uses
These strains are generally derived from E. coli K12, which are unable to produce vitamin B, so this medium is formulated to enhance the growth of nutritionally demanding microorganisms. This strain of E. coli has been further modified through specific mutation to create an auxotrophic strain that is not capable of growth on nutritionally deficient media.
Tryptone provides nitrogen, vitamins, minerals and amino acids essential for growth. Yeast extract is the source of vitamins, particularly of the B-group. Sodium chloride supplies essential electrolytes for transport and osmotic balance. Bacteriological agar is the solidifying agent. If desired, antibiotics can also be added.
LB Agar (Lennox) has a different sodium chloride level than other media such as Luria Agar (Miller’s LB Agar) (LC-1552) or Luria Agar (Miller’s Modification) (LC-1308). This allows selecting the optimum salt concentration of the medium for a specific strain.
Technical specifications
| Solubility | Without residues |
|---|---|
| Appearance | Fine powder |
| Color of the dehydrated medium | Beige |
| Color of the prepared medium | Amber, slightly opalescent |
| Final pH (25 °C) | 7.0 ± 0.2 |
| Amount per litre | 35 g |
| Storage | 2 to 25 °C |
Formula
| Ingredient | g/L |
|---|---|
| Bacteriological agar | 15 |
| Sodium chloride | 5 |
| Tryptone | 10 |
| Yeast extract | 5 |
Preparation and use
Preparation
Suspend 35 grams of medium in one liter of distilled water. Mix well and dissolve by heating with frequent agitation. Boil for one minute until complete dissolution. Sterilize in autoclave at 121 °C for 15 minutes. Cool to 45-50 °C, mix well and dispense into plates.
Instructions for use
- Carry out the experimental procedure according to appropriate use or purpose.
- Inoculate and incubate at a temperature of 35 ± 2 °C for 18-24 hours.
Quality control
Microbiological test
Incubation conditions: 35 ± 2 °C / 18-24 h.
| Microorganism | Specification |
|---|---|
| Escherichia coliATCC 23724 | Good growth |
| Escherichia coliATCC 33694 | Good growth |
| Escherichia coliATCC 33849 | Good growth |
| Escherichia coliATCC 39403 | Good growth |
| Escherichia coliATCC 47014 | Good growth |
Bibliography
- Atlas, R.M., L.C. Parks (1993) Handbook of Microbiological Media. CRC Press, Inc. London.
- Lennox. 1955. Virology 1:190.
- Sambrook, Fritsch and Maniatis. 1989. Molecular cloning: a laboratory manual, 2nd ed. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y.
What you receive
The product
Shipped under controlled temperature when the product requires it.
Lot certificate
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Tracked shipment
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