Question

Which one of the following is most accurate for determining bacterial cell viability?

• A. Gram staining
• B. Colony-forming unit (CFU) count
• C. Optical density
• D. Total cell count using a hemocytometer

Hint:

For determining cell viability, CFU count is often the best option, as it directly measures the number of viable, living cells in a sample.

Answer 1

The Correct Option is B

Colony-forming unit (CFU) count is the most accurate method for determining bacterial cell viability. This technique involves plating a diluted bacterial sample on an agar plate and counting the number of colonies that grow. Each colony originates from a viable bacterium. Gram staining and optical density are not as accurate because they don't specifically measure cell viability, and total cell count using a hemocytometer includes both viable and non-viable cells.