1. Culture media ISO 11290

2. Culture Media in ISO 11290 CONFIRMATION PREENRICHMENT SELECTIVE ENRICHMENT PLATE Biochemical Test Listeria Half Fraser Broth Base Cat. 1183 Listeria Fraser Broth Base Cat. 1182 Listeria Agar Base Oxford Cat. 1133 & Listeria Chromogenic Agar Base Cat. 1345 Motility Hemolysis Carbohydrate utilization Listeria

3. Culture Media in ISO 11290 CONFIRMATION PREENRICHMENT PLATE Biochemical Test Listeria Half Fraser Broth Base Cat. 1183 Listeria Fraser Broth Base Cat. 1182 Listeria Agar Base Oxford Cat. 1133 & Listeria Chromogenic Agar Base Cat. 1345 Esculin is hydrolized to esculetin, that reacts with ferric salts Allows the growth of Listeria with a black color, inhibiting the acompanying flora Incubate at 30ºC during 24 ± 2 hours Peptones / Salts / Buffer Lithium Chloride/ Nalidixic Acid Esculin/Ferric Amonium Citrate Listeria Half Fraser Broth SELECTIVE ENRICHMENT Nalidixic Acid inhibits Gram negative microorganisms Lithium Chloride inhibits Enterococcus that can hydrolize the Esculin

4. Culture Media in ISO 11290 CONFIRMATION PREENRICHMENT PLATE Biochemical Test Listeria Half Fraser Broth Base Cat. 1183 Listeria Fraser Broth Base Cat. 1182 Listeria Agar Base Oxford Cat. 1133 & Listeria Chromogenic Agar Base Cat. 1345 Peptones / Salts / Buffer Lithium Chloride/ Nalidixic Acid Esculin/Ferric Amonium Citrate Listeria Fraser Broth Base Allows the growth of Listeria with a black color, inhibiting the acompanying flora Incubate at 35-37ºC during 24-48 hours Incubate at 35-37ºC during 24-48 hours Nalidixic Acid inhibits Gram negative microorganisms SELECTIVE ENRICHMENT Esculin is hydrolized to esculetin, that reacts with ferric salts Lithium Chloride inhibits Enterococcus that can hydrolize the Esculin

5. Culture Media in ISO 11290 CONFIRMATION PREENRICHMENT PLATE Listeria Half Fraser Broth Base Cat. 1183 Listeria Agar Base Oxford Cat. 1133 & Listeria Chromogenic Agar Base Cat. 1345 Peptones / Salts / Buffer Lithium Chloride/ Esculin/Ferric Amonium Citrate/Other antibiotics Listeria Agar Base Oxford Incubate at 32±2°C during 18-24 hours Listeria monocytogenes and Listeria innocua grow giving the medium a black color Esculin is hydrolized to esculetin, that reacts with ferric salts SELECTIVE ENRICHMENT Listeria Fraser Broth Base Cat. 1182 Biochemical Test Cicloheximide inhibits yeast and molds Lithium Chloride inhibits Enterococcus that can hydrolize the Esculin

6. Culture Media in ISO 11290 CONFIRMATION PREENRICHMENT PLATE Biochemical Test Buffered Peptone water Cat. 1402 Listeria Agar Base Oxford Cat. 1133 & Listeria Chromogenic Agar Base Cat. 1345 Peptones / Salts / Chromogenic Substrate Lithium Chloride/ Antibiotics Listeria Chromogenic Agar Base Incubate at 37ºC during after 24 ± 2 hours.Incubate the negative strains for 24±2 hours more Salmonella growth in magenta colonies Esterase activity cleaves one of the cromogenic substrate, giving the colony a magenta color β-Galactosidase activity cleaves the other chromogenic substrate, giving the colony a green color SELECTIVE ENRICHMENT Listeria Fraser Broth Base Cat. 1182

7. Culture Media in ISO 11290 CONFIRMATION PREENRICHMENT PLATE Biochemical Test Buffered Peptone water Cat. 1402 Listeria Agar Base Oxford Cat. 1133 & Listeria Chromogenic Agar Base Cat. 1345 Motility SELECTIVE ENRICHMENT Listeria Fraser Broth Base Cat. 1182 Hemolysis Carbohydrate Utilization

8. Results