What are the typical autoclave conditions used to sterilize heat-stable media?

What are the typical autoclave conditions used to sterilize heat-stable media?

• A. 121°C for 15-20 minutes under pressure
• B. 100°C for 60 minutes
• C. 150°C for 5 minutes
• D. 90°C for 30 minutes

Answer: (A)

Moist heat under pressure raises the effective sterilization temperature, which is essential to reliably destroy spores and hardy microbes. The standard autoclave cycle for heat-stable media uses saturated steam at about 121°C under pressure (roughly 15 psi) for 15–20 minutes. This combination provides quick heat penetration and enough dwell time to denature proteins and disrupt cellular structures throughout the medium without causing unnecessary damage. Alternatives that stay at lower temperatures, or rely on shorter times or different methods, don’t achieve the same level of sterility reliably.

Moist heat under pressure raises the effective sterilization temperature, which is essential to reliably destroy spores and hardy microbes. The standard autoclave cycle for heat-stable media uses saturated steam at about 121°C under pressure (roughly 15 psi) for 15–20 minutes. This combination provides quick heat penetration and enough dwell time to denature proteins and disrupt cellular structures throughout the medium without causing unnecessary damage. Alternatives that stay at lower temperatures, or rely on shorter times or different methods, don’t achieve the same level of sterility reliably.