Liofilchem Kovac's Reagent 4 x 25 mL

The Liofilchem™ Kovac’s Reagent is a specialized reagent for the indole test, primarily used to detect indole production in Enterobacteriaceae. This reagent allows for rapid differentiation of bacterial species based on their ability to deaminate tryptophan.

Key Features

1. Reliable Indole Detection:
   • Identifies bacteria capable of producing indole through tryptophan degradation.
2. Validated for Clinical Use:
   • Tested with standard control strains for consistent performance.
3. Convenient Packaging:
   • Supplied in 4 x 25 mL bottles, suitable for 100–200 tests.

Kit Contents

• 4 Bottles of Kovac’s Reagent (25 mL each).

Method Principle

• Indole Production:
  • Bacteria producing tryptophanase degrade tryptophan into indole, pyruvic acid, and ammonium.
  • Kovac’s Reagent reacts with indole to form a red-violet compound (cherry-red ring), indicating a positive result.

Applications

1. Clinical Microbiology:
   • Differentiation of indole-positive bacteria (Escherichia coli) from indole-negative species (Proteus mirabilis, Salmonella spp.).
2. Food and Environmental Testing:
   • Identifies indole-producing bacteria in water and food samples.
3. Research:
   • Studies on bacterial metabolism and identification.

Test Procedure

1. Inoculate a pure bacterial culture into a tryptophan-containing medium (e.g., peptone water or tryptic soy broth).
2. Incubate at 35 ± 2°C for 24–48 hours.
3. Add 2–3 drops of Kovac’s Reagent directly to the culture tube.
4. Observe for color change at the broth surface within 30 seconds.

Interpreting Results

Quality Control

• Appearance:
  • Kovac’s Reagent: Clear yellow-green liquid.

Storage and Shelf Life

• Storage:
  • Store at 2–8°C in original packaging, away from heat and light.
• Shelf Life:
  • Valid for 2 years when stored as recommended.

Advantages

• Accurate and Reliable:
  • Provides consistent results for indole detection.
• Rapid Testing:
  • Results observed within 30 seconds after reagent addition.
• Convenient:
  • Ready-to-use reagent in pre-measured bottles.

Warnings and Precautions

1. For in vitro diagnostic use (IVD) only.
2. Handle all reagents and bacterial cultures as potentially infectious.
3. Dispose of waste materials in accordance with local regulations.

Limitations

• Use only tryptophan-containing media (e.g., peptone water).
• Avoid media with glucose or indicators that may interfere with results.
• False positives can occur with mixed cultures or pigmented organisms.
• Indole production from some anaerobes, such as Clostridium spp., may degrade rapidly, leading to false negatives.

Packaging

References

1. Murray, Baron, Pfaller, Tenorev, and Yolken: Manual of Clinical Microbiology (1995).
2. Bayley and Scott’s: Diagnostic Microbiology (1986).
3. Edwin H. Lenette: Manual of Clinical Microbiology (1995).

Why Choose Liofilchem Kovac’s Reagent?

• Proven Accuracy: Validated with standard control strains for reliability.
• User-Friendly: Pre-measured bottles simplify workflows in laboratories.
• Cost-Effective: Each kit provides sufficient reagent for up to 200 tests.