Ch. 23 Physical & Chemical Control Of Microorganisms

Front 1

Sterilization

Back 1

Kills every life form including endospores

Front 2

Commerical Sterilization

Back 2

Sufficient heat treatment to kill endospores of clostridium botulinum in canned food.

Front 3

Disinfection

Back 3

Destruction of vegetative pathogens on inanimate objects.

Front 4

Antisepsis

Back 4

Destruction of vegetative pathogens on living tissue. Almost always chemical.

Front 5

Degerming

Back 5

Removal of microbes from a limited area, such as the skin around an injection site.

Front 6

Sanitization

Back 6

Treatment intended to lower microbial counts on eating and drinking utensils to safe public health levels.

Front 7

Contaminated

Back 7

A sterile object that is harboring microorganisms and viruses.

Front 8

Heat

Back 8

Physical method that is fast, reliable and inexpensive. Involves TDT & TDP

Front 9

Thermal death time (TDT)

Back 9

The length of time required to kill a bacterial population at a given temperature.

Front 10

Thermal death point (TDP)

Back 10

The temperature required to kill a bacterial pupulation at a given temperature.

Front 11

Dry Heat

Back 11

Physical method that uses incineration (only thing used to kill prions), flaming & oxidation.

Front 12

Hot Air Oven

Back 12

This will kill endospores. Radiating dry heat for sterilization. 160 degrees C for 2 hrs. used on glassware, dry powders, etc. works by oxidation, but organics must be removed.

Front 13

Moist Heat

Back 13

This physical method involves boiling water, steam under pressure (aka autoclave)

Front 14

Autoclave

Back 14

This kills endospores at 121.5 degrees C for 15 min. Is the best method for sterilization.

Front 15

Filtration

Back 15

A mechanical method to remove microorganisms by passing a liquid or air through a filter.

Front 16

Radiation

Back 16

Not sporicidal. Incl. UV rays, Ionizing radiation, microwaves. These can alter DNA.

Front 17

Ionizing radiation

Back 17

Xrays or gamma rays. Are short waves that quicly combine with cellular water to produce free radicals. limited to food use.

Front 18

Pasteurizing Dose

Back 18

This does not eliminate all microbes in the food but elimates pathogens.

Front 19

Microwaves

Back 19

Bacteria not affected by this method. These are absorbed by water and theat is transferred to and cooks the food.

Front 20

Drying or Dessication

Back 20

This doesn't necessarily kill, but stops growth. Works by disrupting metabolism is bacteriostatic.

Front 21

Osmotic Pressure

Back 21

Uses salt or sugar for control of microorganisms. Fungus can occur but is not harmful.

Front 22

Plasmolysis

Back 22

This results in loss of water from microbial cells.

Front 23

Low Temperature

Back 23

This slows metabolism; doesn't kill the microorganism. Is bacteriostatic.

Front 24

Chemical methods of Control

Back 24

This method rarely achieve sterilization. It will destroy the pathogenic organism on or in an object.

Front 25

Halogens

Back 25

This chemical method is highly reactive, releases oxygen, strong oxidizers.

Front 26

Strong Oxidizers

Back 26

Inactivate certain proteins and enzyjmes and may change cell membrane structure.

Front 27

Chlorine

Back 27

This chemical method is a halogen combines with water to form hypochlorous acid. Eff. against broad spectrum of organisms incl. most G+ & G-, many viruses, fungi and protozoa. Not sporicidal.

Front 28

Iodine

Back 28

This halogen is larger than a chlorine molecule. More germicical than chlorine.

Front 29

Tincture

Back 29

This substance is dissolved in ethyl alcohol. Used as antiseptic for wounds.

Front 30

Iodophor

Back 30

This antiseptic & disinfectant is a complex of iodine and detergents. advantage is it releases iodine over a long period of time and doesn't stain. Used in pre-op skin preparation aka Betadine.

Front 31

Phenol (carbonic acid, phenolics & bispenols)

Back 31

This is expensive, odorous and harsh to skin.

Front 32

Phenolics

Back 32

these are phenol derivatives that have a germicidal activity and lower toxicity.

Front 33

Bisphenols

Back 33

2 molecules of phenol joined together. Most widely used. Lysol

Front 34

Hexachlorophene

Back 34

pHisoHex is this and is a detergent cream that will retard staphlococcal infections in newborns. Nero damage occurs in high amounts.

Front 35

Chlorhexidine

Back 35

A bisphenol used as a surgical scrub and hand wash and superficial skin wounds.

Front 36

Triclosan

Back 36

A bisphenol that disrupts cell membranes by blocking the synthesis of lipids. Is in sponges, cutting boards.

Front 37

Oligodynamic Action

Back 37

Categorized under heavy metals. Is the inhibition or killing of MOS using a very small amount of chemical substance. denature enzymes & other essential proteins, not sporicidal.

Front 38

Mercury

Back 38

aka Mercuric chloride, used to kill or retard bacteria. Very toxic so it is conbined with other molecules

Front 39

Less toxic forms of Mercury

Back 39

Mercurochrome & Merthiolate

Front 40

Copper

Back 40

aka copper sulfate, used to kill or retard bacteria, chlorophyll containing organisms

Front 41

Silver

Back 41

aka silver nitrate, used as antiseptic and disinfectant, effective against gonococcal organisms that cause blindness in newborns

Front 42

Alcohol

Back 42

different types. protein denaturation and lipid dissolution, bactericial & fungicidal. Used primarily for degerming.

Front 43

Soaps

Back 43

degerming, mechanical removal, aka surfactants, ph around 8.0, fatty acids combined with potassium or sodium hydroxide.

Front 44

Detergent

Back 44

Synthetic chemical acting as a strong surfactant, reduces surface tension, most useful are QUATS.

Front 45

QUATS

Back 45

Cationic derivatives of ammonium chloride in detergents. inhibit enzyme, protein denaturation and disruption of the plasma membrane.

Front 46

Hydrogen Peroxide

Back 46

This reacts with catalase (enzyme in skin cells) to form oxygen and water. Not a good antiseptic but good on inanimate objects.

Front 47

Aldehydes

Back 47

These do sterilize; react with amino & hydroxyl groups of nucleic acids and proteins deactivating them.

Front 48

Formaldehyde

Back 48

37% is formalin, specimen preservative and embalming fluid. Leaves residue and can cause allergies.

Front 49

Glutaraldehyde

Back 49

This is the most effective chemical liquid for sterilizing. A 2% solution can be used for sterilizing. Doesn't damage delicate objects, but does emit fumes.

Front 50

Ethylene Oxide

Back 50

A gas that sterilizes many things amoung them plastic. Is sporicidal, but is carcinogenic and highly explosive.

Front 51

Chlorine Dioxide

Back 51

A gas or liquid that is not a carcinogen and doesn't produce toxic by products.