U.S. Food & Drug Administration
Center for Food Safety & Applied Nutrition

Bacteriological Analytical Manual Online
January 2003

M10a
ALOA (Agar Listeria Ottavani & Agosti) Medium

(Return to Table of Contents)


Meat peptone 18 g
Tryptone 6 g
Yeast extract 10 g
Sodium pyruvate 2 g
Glucose 2 g
Magnesium glycerophosphate 1 g
Magnesium sulphate 0.5 g
Sodium chloride 5 g
Lithium chloride 10 g
Disodium hydrogen phosphate anhydrous 2.5 g
5-bromo-4-chloro-3-indolyl-ß-D-glucopyranoside 0.05 g
Agar, according to gelation-strength 12 g to 18 g
Water, according to volume of fungistat supplement 925-930 ml

Dissolve the dehydrated components or dehydrated complete base in the water by boiling. Adjust the pH, if necessary, so that after sterilization it is 7.2 ± 0.2.

Sterilize by autoclaving for 15 minutes at 121°C.

Supplements: Dissolve 2 g of L-lower-case alpha-Phosphatidylinositol (Sigma P 6636) in 50 ml of cold distilled water.

Stir for about 30 minutes until a homogeneous suspension is obtained.

Autoclave at 121°C for 15 minutes. Cool to 48-50°C.

Dissolve the following compounds individually in the specified solvents and filter-sterilize the solutions: 0.02 g nalidixic acid (sodium salt) in 5 ml of water; 0.02 g of ceftazidime in 5 ml of water; 76700 U of polymyxin B in 5 ml of water; 0.05 g of cycloheximide in 2.5 ml of ethanol and add 2.5 ml of water; 0.01 g of amphotericin B in a mixture of 2.5 ml HCl (1 M) and 7.5 ml dimethylformamide.

Complete medium: Agar base 925 ml (or 930 ml); Nalidixic Acid solution; 5 ml; Ceftazidime solution, 5 ml; Cycloheximide solution, 5 ml (or Amphotericin B solution 10 ml); Polymyxin B solution, 5 ml; L-lower-case alpha-Phosphatidylinositol solution, 50 ml.

This medium is available commercially as the ready-to-use agar medium.



Advisory for BAM Users on Reported Supply Problems for Cycloheximide


B A M   |   B A M Media   |   B A M Reagents   |   Bad Bug Book

Foods Home   |   FDA Home   |   HHS Home   |   Search/Subject Index   |   Disclaimers & Privacy Policy   |   Accessibility/Help

Hypertext updated by bpd/cjm 2005-OCT-21