Skip to main content
Back

Microbiology Chapter 7: Sterilization and Disinfection Concepts

Control buttons has been changed to "navigation" mode.
1/22

Terms in this set (22)

  • Sterilization

    Sterilization is the process of destroying all forms of microbial life, including spores.

  • Commercial sterilization

    Commercial sterilization is the process of killing Clostridium botulinum endospores in canned food to prevent botulism.

  • Disinfection

    Disinfection is the process of eliminating most or all pathogenic microorganisms on inanimate objects, but not necessarily all spores.

  • Antiseptic

    An antiseptic is a chemical agent used on living tissue to reduce the number of microbes.

  • Degerming

    Degerming is the mechanical removal of microbes from a limited area, such as skin around an injection site.

  • Bacteriostatic

    Bacteriostatic agents inhibit bacterial growth without killing the bacteria.

  • Bactericidal

    Bactericidal agents kill bacteria directly.

  • Sanitization

    Sanitization is the process of lowering microbial counts on eating utensils or surfaces to safe public health levels.

  • Thermal Death Point (TDP)

    TDP is the lowest temperature at which all microbes in a liquid culture are killed in 10 minutes.

  • Thermal Death Time (TDT)

    TDT is the minimum time required to kill all microbes at a specific temperature.

  • Decimal Reduction Time (DRT)

    DRT is the time required to kill 90% of the microbes at a given temperature.

  • Pasteurization

    Pasteurization is a mild heat treatment that reduces spoilage organisms and pathogens without sterilizing.

  • Moist Heat

    Moist heat kills microbes by denaturing proteins and includes methods like boiling and autoclaving.

  • Dry Heat

    Dry heat kills microbes by oxidation and includes methods like flaming and hot air ovens.

  • Ionizing Radiation

    Ionizing radiation (e.g., X-rays, gamma rays) kills microbes by damaging DNA and generating reactive molecules.

  • Non-Ionizing Radiation

    Non-ionizing radiation (e.g., UV light) kills microbes by causing thymine dimers in DNA, disrupting replication.

  • Alcohols

    Alcohols kill microbes by denaturing proteins and dissolving lipids; commonly used are ethanol and isopropanol.

  • Ethylene Oxide

    Ethylene oxide is a gaseous sterilant that alkylates proteins and DNA, used for heat-sensitive materials.

  • Halogens

    Halogens like iodine and chlorine kill microbes by oxidizing cellular components.

  • Aldehydes

    Aldehydes (e.g., formaldehyde) kill microbes by cross-linking proteins and nucleic acids.

  • Peroxygens

    Peroxygens such as hydrogen peroxide kill microbes by producing reactive oxygen species that damage cells.

  • Biguanides

    Biguanides disrupt microbial cell membranes and are used as antiseptics (e.g., chlorhexidine).