Intermittent sterilization
Is the "exposure to a temperature of 100°C (flowing steam) for a definite period, usually an hour, on each of several days; at each heating, the developed bacteria are destroyed; spores, which are unaffected, germinate during the intervening periods and are subsequently destroyed.
Dry heat sterilization
What is best used for sterilizing culture media, liquids and heat-sensitive items?
moist heat
The sample is placed in the steam sterilizer or boiled to introduce ________ for 10- 20 minutes, which kills the vegetative cells and mist spores will likely remain.
15-30 minutes
Sterilization takes only ________ and during this time the cell membranes of the microbes hydrolyse and the proteins coagulate and denature, killing the microbial cells.
Nutrient broth
What has already been adjusted by the manufacturer to a specific pH and also contains buffering agents to maintain it?
fastidious bacteria
As the media is nutrient- rich, it provides the optimal environment for ________ like streptococcus pneumoniae, that need specific conditions and nutrients to grow.
concept of boiling
The ________ is based upon the idea that spores are resistant to most sterilization procedures, hence the only way to get rid of them is to give them the opportunity to grow out and kill the cells before they reproduce their endospores.
Dry heat sterilization
________ involves exposing a sample for sterilization in an oven at approximately 170°C for 2 to 3 hours under atmospheric pressure.
Complex media
________ contain many animal or plant tissue- derived compounds such as yeast extract, peptones from plants or albumin serums whose quantity and concentrations are unknown.
MEDIA MIX
Table 1: TABLE SHOWING THE AMOUNT OF WATER AND ________ REQUIRED TO MAKE THE CORRECT AMOUNT OF MEDIUM.
Amount of agar used
(Agar % ÷ 100) × Water
Percentage of media that is agar
Agar ÷ Water
Amount of water present in the media
Media mix ÷ Bottle label
Amount of media mix present in the media
Bottle label × water
Correct media proportions on the bottle label
Media mix ÷ water
The same as the water volume
What is the final volume?
Defined media
What is media has all the chemicals known and none of the components is microbial or animal-derived?