Chapter 13: Control Of Microbial Growth Flashcards
Removing and destroying all microbial life.
Sterilization
Procedure in which added precautions are used to prevent contamination of a person, object or area by microbes.
Sterile (aseptic) technique
Destroying harmful microorganisms; use disinfectants
Disinfection
Destroying harmful microorganism from living tissue; Use antiseptics
Antisepsis
Lowering microbial counts on eating utensils to safe levels
Sanitization
Infected by contact or association
Contamination
Killing of microbes
Microbiocidal
Inhibiting, not killing microbes
Microbiostatic
Time (in minutes) required to kill 90% of bacterial population at a given temperature; also called D value
Decimal Reduction Time (DRT)
Lowest temperature at which all cells in culture are killed in 10 minutes
Thermal Death Point (TDP)
Time during which all cells in culture are killed
Thermal Death Time (TDT)
Process of mild heating to kill particular spoilage microorganisms or pathogens
Pasteurization
The effectiveness of treatment depends on the following:
Number of microbes
Environment
Time of exposure
Microbial characteristics
The physical method “heat” controls microbes
Killing microbes by denaturing proteins
The physical method “cold” of microbial control
Inhibits microbes
The physical method “Dessication” of microbial control
Removal of water and prevents metabolism
The physical method “radiation” of microbial control
Damages DNA
The physical method” filtration” microbial control
Physically removes microbes
Phenolics: Category of disinfectants
Disrupt Plasma membranes
Heavy metals: category of disinfectants
Denature proteins
Halogens: Category of disinfectants
Alter protein synthesis and membrane
Alcohol: category of disinfectants
Denature proteins and dissolve lipids
Surfactants: category of disinfectants
Decrease tension between molecules lying on the surface of liquid; emulsification
Alkylating agents: category of disinfectant
Inactivates enzymes and nucleic acids
What is the purpose of the disk diffusion test?
It is used to determine microbial susceptibility to chemotherapeutic agents
What type of microbes is most resistant to disinfection and autoclaving
Prions
