Controlling Microbial Growth In The Environment Flashcards
Antisepsis
Reduction in the number of microorganisms and viruses, particularly potential pathogens on living tissue
Aseptic
Refers to an environment or procedure free of pathogenic contaminants
-cide or -cidal
Suffixes indicating destruction of a type of microbe
Degerming
Removal of microbes by mechanical means
Disinfection
Destruction of most microorganisms and viruses on non-living tissue
Pasteurisation
Use of heat to destroy pathogens and reduce the number of spoilage microorganisms in food and beverages
Sanitisation
Removal of pathogens from objects to meet public health standards
- stasis
- static
Suffixes indicating inhibition but not complete destruction of a type of microbe
Sterilisation
Destruction of all microorganisms and viruses in or on an object
Action of antimicrobial agents
Alteration of cell walls - when damaged effects of osmosis can cause cell to burst
Cytoplasmic membrane- contents leak out
Non-enveloped viruses can better tolerate harsh conditions
Damage to proteins and nucleic acids -alter or destroy, fatal mutants, halt synthesis
Most resistant to least resistant
Prions Bacterial endospores Mycobacterium Cysts of Protozoa Active stage Protozoa (trophozoites) Most gram negative bacteria Fungi Nonenveloped viruses Most gram positive bacteria Enveloped viruses
High level germicides
Kill all pathogens including endospores
Intermediate-level germicides
Kill fungal spores, protozoan cysts, viruses and pathogenic bacteria
Low-level germicides
Kill vegetative bacteria, fungi, Protozoa and some viruses
Moist heat
Used to disinfect, sanitise, sterilise and pasteurise
Denatures proteins and destroys cytoplasmic membranes
More effective than dry heat
Boiling
Autoclaving
Pasteurisation
Ultrahigh-temperature sterilisation