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Indole Test Procedure: Inoculation: Using a sterile inoculating loop, transfer a loopful of the bacterial culture into a tube of peptone water or tryptophan broth. Incubation: Incubate the tube at 35–37°C for 24 to 48 hours. Addition of Reagent: After incubation, gently add 5 drops of Kovac’s reagent down the inner wall of the test tube without shaking. Observation: Allow the tube to stand undisturbed for a few minutes. A red or pink ring at the top indicates a positive indole test. No color change indicates a negative result. 🎯 Why is the Indole Test Important? Helps identify indole-producing bacteria Used in medical and clinical diagnostics Commonly applied in water and food safety testing #IndoleTest #Microbiology #ScienceExperiment #ChemistryLab 

The Membrane Filter Method is a widely used microbiological technique for detecting and counting bacteria in water and liquid samples. 🔬 Procedure :  Take a measured volume of the sample (usually 100 mL). Pass it through a sterile membrane filter (0.45 µm pore size) using a vacuum pump. Place the filter carefully onto a selective agar plate. Incubate the plate at the required temperature (typically 35–37°C) for 24–48 hours. After incubation, count the colonies that have grown on the filter surface. Calculate the result as CFU per 100 mL of sample.

OXIDASE TEST..... . . . In this short video, we demonstrate the oxidase test  a well-known oxidase-positive bacterium. This test is used to detect the presence of the enzyme cytochrome c oxidase, which is involved in the electron transport chain. 🧪 Procedure: Take a clean, sterile oxidase disc or filter paper. Using a sterile loop or wooden stick, pick a small colony of Pseudomonas from a fresh agar plate. Rub the colony gently on the disc or moistened filter paper. Observe the color change within 10–30 seconds. ✅ Positive Result: A purple or dark blue color appears — indicates Pseudomonas is oxidase positive. 🧫 Test Organism: Pseudomonas spp. 🔬 Application: Biochemical Identification of Bacteria 📍 Category: Microbiology | Biochemistry | Chemistry Practical #Oxidase