What are the differences between gram stain and culture?
Posted September 17, 2022
Gram stain and culture are two completely different techniques with several significant differences between them.
|Basis of differentiation
|Is a differential staining technique used to identify the presence of bacteria and differentiate between types of bacteria
|Is a method of preparing and maintaining microorganism in a laboratory
|Is used to differentiate bacteria into two main groups – gram positive bacteria and gram negative bacteria
|Is used to multiply microorganisms for various purposes such as testing, chemical purification, and storage among others
|Components used in the procedure
|Uses two stains – crystal violet and safranin, mordant such as iodine solution, decolorizer such as ethanol, and water
|Uses an array of nutrient-rich culture media that may be solid, semi-solid or liquid
|Basis of technique
|Based on the differences in the thickness of the peptidoglycan layer of the cell wall
|Based on the ability of microorganisms to grow and multiply inside a favorable culture media
|Gram positive bacteria appear purple in color and gram negative bacteria appear pink in color
|Colonies of the microorganisms are visible on solid and semi-solid media. In liquid media, microorganisms are visible in suspended form