Question

List the reagents used for spore staining:

a. Primary dye
b. Decolorizer
c. Counter stain

Answer 1

In spore staining, malachite green is used as the primary dye, ethanol or an acetone/ethanol solution as the decolorizer, and safranin as the counterstain, resulting in green-stained endospores and pink vegetative cells.

Step-by-step explanation:

For spore staining, the following reagents are typically used:

1. Primary dye: Malachite green is used as the primary stain. The use of heat or a lengthy exposure time is often required to encourage the endospores to absorb this water-soluble dye.
2. Decolorizer: Ethanol or an acetone/ethanol solution serves as the decolorizer. It is designed to remove the primary dye from all but the endospores, which remain green after staining.
3. Counterstain: Safranin is applied after the decolorization step to stain the vegetative cells pink for contrast, making the green color of the endospores more visible.

The end result shows endospores as green and the vegetative cells as pink, providing clear differentiation under a microscope.