Vegetable LB Agar (Lennox)

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.

In this case, the ingredients are animal-free in order to minimize the risk of bovine spongiform encephalopathy in culture media containing bovine materials. Vegetable origin peptone provides nitrogen, vitamins, minerals and amino acids essential for growth. Yeast extract is a source of vitamins, particularly the B-group, essential for bacterial growth. Sodium chloride supplies essential electrolytes for transport and osmotic balance. Bacteriological agar is the solidifying agent.

Vegetable LB Agar (Lennox) has a different sodium chloride level than other media such as Luria Agar (Miller 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.

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

1. Carry out the experimental procedure according to appropriate use or purpose.
2. Inoculate and incubate at a temperature of 35 ± 2 °C for 18-24 hours.

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