Chemical Control of Microbial Growth Flashcards
➢agents that kill viruses
Viricidal
➢agents that kill bacteria
Bactericidal
➢agents that kill fungi
Fungicidal
an agent that inhibits bacterial
growth
Bacteriostatic
an agent that inhibits fungal
growth
Fungistatic
an agent that inhibits the
growth of viruses
Viristatic
➢a chemical agent that destroys all forms of microbial life, including
endospores.
* used for decontamination or sterilization in situations where it is
impractical or impossible to use heat or radiation.
Sterilant
➢employs gases such as ethylene oxide or aldehydes such as formaldehyde or glutaraldehyde to sterilize heat-sensitive materials such as thermometers, lensed instruments, polyethylene tubing, catheters, and reusable medical and dental equipment
Cold sterilization
➢ chemical that kill microorganisms but not necessarily endospores and are primarily used on surfaces
Disinfectant
➢a chemical agent that destroys all forms of microbial life
Disinfectant
➢an agent that reduces microorganisms to a safe level, but may not eliminate them
Sanitizer
➢ widely used in the food industry to treat surfaces such as mixing and cooking equipment, dishes, and utensils, and are also used for dry hand washing when water is unavailable.
Sanitizer
➢ a chemical agent that kills or inhibits growth of microorganisms and is sufficiently nontoxic to be applied to living tissue
Antiseptic (germicide)
➢used for hand washing or for treating surface wounds
Antiseptic (germicide)
can be both an antiseptic and a disinfectant, depending on the concentration and exposure time employed
Ethanol
In 1928, __________ observed that the growth of the bacterium _____________ was inhibited in the area surrounding the colony of a mold that had contaminated a Petri plate.
Alexander Fleming; Staphylococcus aureus
➢an antimicrobial agent, usually produced naturally by a bacterium or fungus.
Antibiotic
The mold Alexander Fleming identified was __________, and its active compound, which was isolated a short time later, was named _________.
Penicillium notatum; penicillin
➢antibiotics that affect a broad range of gram-positive or gram-negative bacteria.
Broad-spectrum Antibiotics
Antimicrobial drugs are either:
bactericidal or bacteriostatic
Antimicrobial drugs target certain essential functions
of the microbe. Mechanisms of action include:
✓inhibiting cell wall synthesis
✓ inhibiting protein synthesis
✓inhibiting nucleic acid synthesis
✓ injuring the plasma membrane
✓inhibiting synthesis of essential metabolites
➢occurs when bacteria change in response to the use of these medicines
Antibiotic resistance
There are only a few mechanisms of microbial resistance to antimicrobial agents:
✓blocking the drug’s entry into the cell;
✓inactivation of the drug by enzymes;
✓alteration of the drug’s target site;
✓efflux of the drug from the cell; or
✓alteration of the metabolic pathways of the
host.
Antimicrobial activity can be measured by
determining the smallest amount of the agent
needed to inhibit the growth of a test organism, a
value called the…
minimum inhibitory concentration (MIC)
