1. Guided Culture<ol><li>Salmonella spp. PCR positive sample<ol style='list-style-type:decimal;'><li>Selective culture in the medium<ol style='list-style-type:decimal;'><li>Add 100 &#956;L of pre-enrichment culture into 5 mL of Selenite Cystine medium in a test tube. Incubate at 36 &#176;C for 18&#8211;24 h in an incubator.</li></ol></li><li>Separating culture on a plate<ol style='list-style-type:decimal;'><li>Collect one loop of the culture with a micro-loop and spread it onto an XLD plate or a Salmonella chromogenic agar plate. Incubate at 36 &#176;C for 18-24 h in an incubator.</li></ol></li></ol></li></ol>

<table><tbody><tr><td>Selenite Cystine medium</td><td>LandBridge</td><td>CM225</td><td> </td></tr><tr><td>XLD</td><td>LandBridge</td><td>CM219</td><td> </td></tr><tr><td>Salmonella chromogenic agar</td><td>CHROMagar</td><td>SA130</td><td> </td></tr><tr><td>Micro-loop</td><td>Weierkang</td><td>W511</td><td> </td></tr><tr><td>Incubator</td><td>Jinghong</td><td>DNP-9082</td><td> </td></tr></tbody></table>

selective enrichment and identification of salmonella spp. using xylose lysine deoxycholate and chromogenic agar

Selective Enrichment and Identification of Salmonella spp. Using Xylose Lysine Deoxycholate and Chromogenic Agar

Source: <a href='https://app.jove.com/v/58200/a-high-throughput-platform-for-screening-salmonella-sppshigella'>Yang, Z., et al. A High-throughput Platform for the Screening of Salmonella spp./Shigella spp.. J. Vis. Exp. (2018)</a>This video demonstrates the selective enrichment and identification of Salmonella using xylose lysine deoxycholate (XLD) and chromogenic agar. Selenite broth promotes Salmonella growth, while XLD agar reveals black-centered colonies through hydrogen sulfide production. Chromogenic agar confirms the identity via enzyme-mediated pigment formation, enabling species-level identification.

Source: Yang, Z., et al. A High-throughput Platform for the Screening of Salmonella spp./Shigella spp.. J. Vis. Exp. (2018)This video demonstrates the ...

Inoculate a culture containing both Salmonella and non-Salmonella species into a selenite cystine medium, and incubate.Selenite inhibits the growth of selenium-sensitive bacteria by disrupting their metabolic processes.However, selenium-tolerant bacteria, including Salmonella, can metabolize selenite and grow.Streak the culture onto Xylose lysine deoxycholate or XLD agar, and incubate.Salmonella reduces sodium thiosulfate in XLD agar to hydrogen sulfide, which reacts with ferric ions in the medium to form black iron sulfide, producing colonies with black centers.In contrast, non-Salmonella species that do not produce hydrogen sulfide form colonies without black centers, allowing visual differentiation from Salmonella.Select a black-centered colony and streak it onto Salmonella chromogenic agar for enhanced specificity.Chromogenic agar contains Salmonella-specific enzyme substrates linked to chromophores.Salmonella enzymes cleave these substrates, releasing the chromophores and forming pigmented colonies.Select these colonies for further analysis.Add 100 microliters of the pre-enrichment culture to five milliliters of selenite crystal medium. Then, incubate the culture at 36 degrees Celsius for 18 to 24 hours. Next, collect one loop of the culture and spread it onto a plate.Then, incubate the plate at 36 degrees Celsius for 18 to 24 hours. After incubation, select suspicious colonies and transfer them to a plate. Incubate the plate at 36 degrees Celsius for 18 to 24 hours.

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Selectieve verrijking en identificatie van Salmonella spp. met behulp van xyloselisinedeoxycholaat en chromogeen agar

648 Views. Breng een cultuur aan die zowel Salmonella als niet-Salmonella soorten bevat in een seleniet cystine medium en incubeer.Seleniet remt de groei van seleengevoelige bacteriën door hun metabolische processen te verstoren.Echter, seleentolerante bacteriën, inclusief Salmonella, kunnen seleniet metaboliseren en groeien.Streep de cultuur op Xylose lysine deoxycholate of XLD agar en incubeer.Salmonella reduceert natriumthiosulfaat in XLD agar...

Selective Enrichment and Identification of Salmonella spp. Using Xylose Lysine Deoxycholate and Chromogenic Agar

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Naam	Bedrijf	Catalogusnummer
Selenite Cystine medium	LandBridge	CM225
XLD	LandBridge	CM219
Salmonella chromogenic agar	CHROMagar	SA130
Micro-loop	Weierkang	W511
Incubator	Jinghong	DNP-9082