1.03867

GranuCult^® plus Deoxycholate Hydrogen sulfide Lactose Agar

acc. SAKAZAKI

• UNSPSC Code: 41106213
• NACRES: NA.74

Properties

• Quality Level: 200
• form: powder
• technique(s): microbiological culture: suitable
• application(s): food and beverages; pharmaceutical
• suitability: nonselective for enterobacteriaceae

Description

General description

GranuCult^® plus Deoxycholate Hydrogen sulfide Lactose (DHL) Agar is a nutrient rich medium to detect and isolate Gram-negative bacteria, from different materials. H2S production is indicated by a blackening of the colonies due to formation of iron sulfide. Although Proteus is H2S-positive, its colonies are not black.
Colonies of Proteus, Morganella, Rettgerella and Providencia are, however, surrounded by dark brown zones, which occur, because these species act on the phenylalanine of the peptone to produce phenylpyruvate, which forms an iron complex with iron(III) ions.
The sucrose content of the medium permits differentiation of weakly lactose-positive or lactose-negative, sucrose-positive species from sucrose- and lactose-negative Enterobacteriaceae.
The deoxycholate largely suppresses the growth of Gram-positive bacteria and prevents the swarming of Proteus species. This medium provides a rich nutrient base and contains a relatively low concentration of the inhibitor deoxycholate. These properties permit growth of even fastidious strains of Salmonella and Shigella. The colonies formed are considerably larger than those found on other selective culture media. Proteus, Morganella, Rettgerella and Providencia can be differentiated from Salmonella.
Neutral Red is a pH indicator and agar is the solidifying agent. .

Application

GranuCult^® plus Deoxycholate Hydrogen sulfide Lactose (DHL) Agar is used to isolate medium to detect and isolate Gram-negative bacteria from different materials. The gram-positive bacterial growth is inhibited by the medium properties that accompany the test sample.

Other Notes

DHL (Deoxycholate Hydrogen sulfide Lactose) agar acc. to SAKAZAKI is also known as Sakazaki DHL agar.

Footnote

We offer two media types: the superior granulated GranuCult^® and the cost-efficient powdered NutriSelect^® culture media, depending on your needs.
The designations basic, plus, or prime are added to indicate the quality control level, from basic quality control to standard QC plus to prime for full regulatory compliance.

Legal Information

GRANUCULT is a registered trademark of Merck KGaA, Darmstadt, Germany

NutriSelect is a registered trademark of Merck KGaA, Darmstadt, Germany

Safety Information

• Storage Class Code: 11 - Combustible Solids
• WGK: WGK 3