What is the purpose of Decolorizer in Gram staining?

What is the purpose of Decolorizer in Gram staining?

The decolorizer, ethyl alcohol, is the most crtitical step. Ethyl alcohol is a nonpolar solvent, and thus penetrates the cell walls of Gram negative cells more readily and removes the crystal violet-iodine complex.

Why do you use decolorizing agent?

Acid-fast Stain: Carbolfuchsin is the primary stain which will be able to penetrate the wax-like cell walls of the acid-fast organism and stain them red. A decolorizing agent is then used to remove the primary stain from non-acid fast organisms.

What is the decolorizing agent in the Gram stain?

Either acetone or ethyl alcohol can be used as the decolorizing agent. The alcohol dissolves lipids found in the outer cell membrane of Gram-negative bacteria, allowing the crystal violet-iodine complex to leak out of the thinner peptidoglycan layer.

What is the function of methylated spirits in the Gram stain process?

After staining the sample with crystal violet, ethyl alcohol is used to decolorize the sample. It achieves its purpose by dehydrating the peptidoglycan layer by tightening and shrinking it.

What is the principle of a Gram stain?

The basic principle of gram staining involves the ability of the bacterial cell wall to retain the crystal violet dye during solvent treatment. Gram-positive microorganisms have higher peptidoglycan content, whereas gram-negative organisms have higher lipid content.

What is the importance of Gram staining?

The main benefit of a gram stain is that it helps your doctor learn if you have a bacterial infection, and it determines what type of bacteria are causing it. This can help your doctor determine an effective treatment plan.

What happens if you don’t add Decolorizer to a Gram stain?

The decolorizer should stay on the slide for no more than 15 seconds! If the decolorizer is left on too long, even gram positive cells will lose the crystal violet and will stain red. The staining procedure is here.

What does alcohol do to Gram negative bacteria?

Alcohol exposure can promote the growth of Gram-negative bacteria in the intestine, which may result in accumulation of endotoxin.

What happens if you skip the Decolorizer in a Gram stain?

What diseases are diagnosed by using the acid fast stain?

It’s also known as an acid-fast bacillus (AFB) stain or a tuberculosis (TB) smear. A doctor typically orders the test to determine if a person has tuberculosis (TB) or another type of mycobacterial infection.

Why 95% ethanol is used in gram stain?

Gram-negative cell walls contain a high concentration of lipids which are soluble in alcohol. The decolorizer dissolves the lipids, increasing cell-wall permeability and allowing the crystal violet-iodine complex to flow out of the cell. The color of the counterstain must contrast with that of the primary stain.

What is difference between gram positive and negative?

Gram positive bacteria possess a thick (20–80 nm) cell wall as outer shell of the cell. In contrast Gram negative bacteria have a relatively thin (<10 nm) layer of cell wall, but harbour an additional outer membrane with several pores and appendices.