Salmonella Chromogenic Agar – 65 g
Product Overview
Salmonella Chromogenic Agar is a selective and differential culture medium designed for the isolation and presumptive identification of Salmonella species. Its chromogenic reaction helps distinguish presumptive Salmonella colonies by their characteristic purple appearance.
This dehydrated agar medium is suitable for microbiology laboratories and routine testing applications where the isolation and differentiation of Salmonella are required.
Under the specified quality control conditions, typical Salmonella strains produce purple colonies after incubation at 36 ± 1°C for 18–24 hours. Other organisms may show different colony appearances or be inhibited, helping support the differentiation process.
Product Details
- Product Name: Salmonella Chromogenic Agar
- Product Code: 10326
- Package Size: 65 g per bottle
- Medium Type: Dehydrated chromogenic agar
- Intended Application: Selective isolation and differentiation of Salmonella
- Typical Salmonella Colony Appearance: Purple
- Incubation Reference: 36 ± 1°C for 18–24 hours
- Final pH: 7.3 ± 0.2 at 25°C
- Shelf Life: 2 years
Key Features
- Chromogenic differentiation: Presumptive Salmonella colonies typically appear purple.
- Selective and differential medium: Designed to support the isolation and differentiation of Salmonella from other microorganisms.
- Distinct colony appearances: Different organisms may produce purple, blue, or colorless colonies, or show inhibited growth under the specified quality control conditions.
- Convenient dehydrated format: Supplied as a 65 g bottle for laboratory medium preparation.
- Defined quality control criteria: Includes reference strains and specified growth characteristics for quality assessment.
- Routine laboratory application: Suitable for microbiological testing workflows requiring Salmonella isolation and presumptive identification.
Intended Use
This medium is intended for the selective isolation and differentiation of Salmonella in microbiological laboratory testing.
It is designed to help users distinguish presumptive Salmonella colonies based on their characteristic purple coloration and the different growth or color reactions of other organisms.
The characteristic colony appearance is a presumptive identification feature. Further confirmation should be performed using appropriate validated identification methods.
Product Specifications
| Parameter | Specification |
|---|---|
| Product Name | Salmonella Chromogenic Agar |
| Product Code | 10326 |
| Package Size | 65 g / Bottle |
| Physical Form | Dehydrated powder |
| Medium Type | Selective and differential chromogenic agar |
| Intended Organisms | Salmonella species |
| Typical Salmonella Appearance | Purple colonies |
| Incubation Temperature | 36 ± 1°C |
| Incubation Time | 18–24 hours |
| Final pH | 7.3 ± 0.2 at 25°C |
| Shelf Life | 2 years |
Medium Composition
The formulation per 1,000 mL is provided below:
| Ingredient | Amount |
|---|---|
| Recombinant Peptone | 25.0 g |
| Comprehensive Nutrients | 25.0 g |
| Chromogenic Agent | 0.5 g |
| Agar Powder | 14.0 g |
| Final pH | 7.3 ± 0.2 at 25°C |
The chromogenic agent is listed according to the supplied formulation. Its specific chemical identity is not stated.
Preparation Instructions
According to the supplied manufacturer instructions:
- Suspend 6.5 g of dehydrated medium in 100 mL of distilled or deionized water.
- Heat and bring to a boil for approximately 1 minute, until the agar is completely dissolved.
- Allow the prepared medium to cool to approximately 50°C.
- Mix thoroughly and prepare plates.
Use the preparation and handling procedure specified by the manufacturer and applicable laboratory procedures. Do not modify the preparation conditions without appropriate validation.
Quality Control Specifications
Physical and Chemical Quality Control
| Test Item | Acceptance Criteria |
|---|---|
| Dehydrated Appearance | White or light yellow powder |
| Moisture Content | ≤ 5% |
| Prepared Plate Appearance | Colorless, without obvious impurities |
| pH | 7.3 ± 0.2 |
| Gel Strength | 550–650 g/cm² |
Microbiological Quality Control
Reference strains are evaluated for growth, selectivity, and colony characteristics after incubation at 36 ± 1°C for 18–24 hours.
| Reference Organism | Strain Number | Expected Result |
|---|---|---|
| Salmonella enterica serovar Typhi | ATCC 14028 | Growth rate ≥ 85%; purple colonies |
| Salmonella enterica serovar Typhimurium | CMCC (B) 50115 | Growth rate ≥ 85%; purple colonies |
| Salmonella enterica serovar Paratyphi B | CMCC (B) 50094 | Growth rate ≥ 85%; purple colonies |
| Escherichia coli | ATCC 25922 | Blue colonies |
| Proteus mirabilis | ATCC 12453 | Colorless colonies |
| Staphylococcus aureus | ATCC 25923 | Complete inhibition under the specified QC conditions |
| Enterococcus faecalis | ATCC 29212 | Complete inhibition under the specified QC conditions |
The listed reference strains and expected results are supplied as product quality control information. Actual results may depend on laboratory conditions and test procedures.
Colony Appearance Guide
- Presumptive Salmonella: Purple colonies.
- Escherichia coli: Blue colonies.
- Proteus mirabilis: Colorless colonies.
- Staphylococcus aureus: Complete inhibition under the specified quality control conditions.
- Enterococcus faecalis: Complete inhibition under the specified quality control conditions.
Colony color is a presumptive differentiation characteristic and should not be treated as definitive species identification.
Packaging and Shelf Life
- Package: 65 g bottle
- Product Code: 10326
- Shelf Life: 2 years
Refer to the product label or manufacturer documentation for the specified storage temperature, storage conditions, and expiry date.
Important Notes
- For laboratory microbiological use.
- Use appropriate laboratory biosafety procedures when handling microorganisms and prepared culture media.
- Follow the manufacturer’s instructions for preparation, handling, and quality control.
- Colony color and growth characteristics are presumptive results and may require further confirmation.
- Storage conditions should follow the product label and manufacturer documentation.
Frequently Asked Questions
Q1: What is Salmonella Chromogenic Agar used for?
It is a selective and differential culture medium designed for the isolation and presumptive identification of Salmonella species in microbiological laboratories.
Q2: What color are typical Salmonella colonies on this medium?
Typical Salmonella colonies are purple under the specified quality control conditions.
Q3: How long does incubation take?
The supplied quality control method specifies incubation at 36 ± 1°C for 18–24 hours.
Q4: What is the package size?
This product is supplied in a 65 g bottle.
Q5: What is the final pH of the medium?
The specified pH is 7.3 ± 0.2 at 25°C.
Q6: What is the shelf life?
The stated shelf life is 2 years. Please refer to the product label for the expiry date and storage instructions.
Q7: Can purple colonies be considered confirmed Salmonella?
No. Purple coloration is a presumptive characteristic. Further confirmation should be performed using appropriate validated identification methods.
Q8: Is this product supplied as ready-to-use agar plates?
No. This product is supplied as dehydrated powder and requires preparation before use.
Product Disclaimer
This product is intended for professional laboratory use. Product information and quality control characteristics are provided for technical reference. Users should follow applicable laboratory procedures and verify presumptive findings using suitable confirmatory methods.
