Exam 4 Ch 7 Flashcards
Sterilization
The destruction of all microbial life
Clostridium SP
The bacteria that all can goods are trying to get rid of using commercial sterilization
Downside of commercial sterilization
Heat tolerant organisms May survive
Disinfection
The destruction of all vegetative cells
May require steam
Chemicals
UV light
Vegetative cells
Metabolically active and fully developed cells
Antisepsis
Reducing the microbe number to a safe public health. ( restaurant issue)
Degerming
The mechanical removal of microbes
Germicide
Kills microbes
Fungicide
Kills fungi
Virucide
Deactivates viruses
Sepsis
Indicates bacterial infection or contamination
Asepsis
No bacterial infection or contamination
Cide versus static
Cide kills
Static slows growth or stops it
Bacterostatic
Stops the growth of bacteria
What four factors influence the effectiveness of a antimicrobial treatment
Number of microbes
Environment (what organics are present, organics could include gauze cotton ball tongue depressors)
Time of exposure (how long you leave the treatment on) typically 5 minutes covered with paper towel, soaked and disinfectant
Microbial evolution (have they evolved, what have they become?)
What are the 2 actions of microbial control agents?
Alters membrane permeability (everything will leak out of the cell and the cell will die)
Damages enzymes and or DNA (Makes metabolic processes stop)
What are the physical methods of control?
Heat
Filtration
Low temperatures
Desiccation
Osmotic pressure
Radiation
Thermal death point( TDP)
The lowest temperature of which all microbes in a liquid will be killed in 10 minutes
Thermal death time( tdt)
The minimum length of time for all organisms to be killed at a given temperature
Downside is if you go too high, you will destroy your product
Decimal reduction time( DRT)
The time in minutes in which 90% of a bacterial population is killed at a given temperature
Boiling as a physical method of control
Kills pathogens, viruses, fungi, and fungal spores
Hepatitis virus can live through 30 hours of boiling
Autoclave as a moist heat physical method of control
Like a giant pressure cooker
It is steam under pressure
Typically at 15 psi will kill everything
Can kill spores in 15 minutes
A common way to sterilize medical equipment
How long can clostridium spores survive? Boiling
They can survive 20 hours of boiling
Pasteurization as a physical method of control using moist heat
