Thermo Scientific™ Oxoid™ Triple Sugar Iron (TSI) Agar (Dehydrated)

The Thermo Scientific™ Oxoid™ Triple Sugar Iron Agar (Dehydrated) is a composite medium used to differentiate Enterobacteriaceae based on their ability to ferment lactose, sucrose, and glucose, as well as produce hydrogen sulfide (H₂S). This medium builds on the formulation of Kligler Iron Agar with the addition of sucrose for enhanced differentiation of sucrose-fermenting species. It is a vital tool for microbiological analysis in clinical, food, and environmental laboratories.

Key Features

1. Comprehensive Differentiation:
   • Differentiates bacteria based on:
     • Lactose, sucrose, and glucose fermentation.
     • Gas production.
     • Hydrogen sulfide (H₂S) production.
2. Reliable Composition:
   • Peptone, yeast extract, and Lab-Lemco powder provide nitrogen and trace elements.
   • Sodium thiosulfate and ferric ions act as the H₂S indicator system.
   • Phenol red serves as the pH indicator for carbohydrate fermentation.
3. Easy-to-Interpret Results:
   • Acid production turns the medium yellow.
   • Alkaline reactions retain or revert to a red color.
   • Black precipitate indicates H₂S production.
4. Wide Application:
   • Recommended for the presumptive identification of colonies from plating media such as:
     • Salmonella Shigella Agar.
     • Bismuth Sulfite Agar.
     • MacConkey Agar No. 3.

Typical Reactions in Triple Sugar Iron Agar

Specifications

Applications

1. Clinical Microbiology:
   • Identifies Enterobacteriaceae in clinical specimens.
2. Food Microbiology:
   • Detects foodborne pathogens such as Salmonella and Shigella.
3. Environmental Testing:
   • Differentiates enteric bacteria in water and soil samples.
4. Research:
   • Studies metabolic activities of bacteria, including sugar fermentation and sulfur metabolism.

Preparation Instructions

1. Suspend 65g of Triple Sugar Iron Agar powder in 1 liter of distilled water.
2. Heat to dissolve completely.
3. Dispense into test tubes to a depth of approximately 5cm.
4. Sterilize by autoclaving at 121°C for 15 minutes.
5. Cool tubes in a slanted position to create a slant and butt.

Advantages

• Enhanced Differentiation: Includes sucrose to identify sucrose-fermenting bacteria.
• Reliable and Reproducible: Standardized formulation ensures consistent results.
• Multiple Indicators: Facilitates visual differentiation through color changes and H₂S precipitate formation.
• Wide Application: Effective for clinical, food, and environmental microbiology.

Packaging

• Quantity: 500g of dehydrated powder.
• Yield: Prepares 7.7L of medium.

Why Choose Triple Sugar Iron Agar?

• Provides comprehensive differentiation of enteric bacteria.
• Recommended by international standards for microbiological analysis.
• Trusted by microbiologists for its accuracy and reliability.