Sodium thioglycolate in the medium consumes oxygen and permits the growth of obligate anaerobes. This, combined with the diffusion of oxygen from the top of the broth, produces a range of oxygen concentrations in the medium along its depth.
What are the 4 steps of Gram staining?
The performance of the Gram Stain on any sample requires 4 basic steps that include applying a primary stain (crystal violet) to a heat-fixed smear, followed by the addition of a mordant (Gram’s Iodine), rapid decolorization with alcohol, acetone, or a mixture of alcohol and acetone and lastly, counterstaining with …
What is Gram staining used for?
What is it used for? A Gram stain is most often used to find out if you have a bacterial infection. If you do, the test will show if your infection is Gram-positive or Gram-negative. A Gram stain may also be used to diagnose fungal infections.
What is the procedure of Gram staining?
The Gram stain involves staining bacteria, fixing the color with a mordant, decolorizing the cells, and applying a counterstain.
- The primary stain (crystal violet) binds to peptidoglycan, coloring cells purple. …
- Gram’s iodine (iodine and potassium iodide) is applied as a mordant or fixative.
What are the 2 types of Gram stain?
Gram staining is a bacteriological laboratory technique used to differentiate bacterial species into two large groups (gram-positive and gram-negative) based on the physical properties of their cell walls.
Why iodine is used in Gram staining?
Gram’s iodine is used in Gram staining procedure to differentiate gram positive and gram negative organisms. Gram’s iodine acts as a mordant that causes the crystal violet to penetrate and adhere to the gram –positive organisms.