Disinfectants, Antimicrobial Susceptibility & Anaerobic Techniques

Vocabulary-style flashcards covering key terms from disinfectant types, antimicrobial susceptibility testing, the RapID ONE system, and anaerobic culture techniques.

Chemical germicides

Substances designed to reduce the number of pathogens.

Disinfectants

Germicides intended for use on non-living surfaces such as floors, instruments, or countertops.

Disinfection

Process that destroys vegetative pathogens on a surface with chemical agents; reduces or inhibits growth but does not sterilize.

Antiseptics

Germicides formulated for application to living tissue, e.g., mouthwash or betadine.

Use-Dilution Test

Laboratory method that determines how much a disinfectant can be diluted and still remain effective against pathogens.

Sanitation (Sanitizing)

Cleaning process that both removes debris and disinfects to reduce microbial load.

Sterilization

Highest level of pathogen control; destroys all forms of life, including endospores, on or in a material.

Phenolics

Disinfectant category derived from phenol; found in some household cleaners, mouthwashes, and handwashes.

Phenol (Carbolic acid)

Oldest known disinfectant/antiseptic; classic example is Lysol, first used by Joseph Lister.

Bisphenol (Phisohex)

Compound containing two phenolic groups linked by a bridge; used as a disinfectant soap.

Alcohols (as disinfectants/antiseptics)

Agents such as isopropyl or ethyl alcohol; commonly used on skin before injections.

Oxidizing agents

Disinfectants that kill via oxidation, e.g., hydrogen peroxide or household bleach.

Halogens

Strong oxidizing disinfectants that include iodine (betadine), chlorine, bromine, and fluorine.

Surfactants

Soaps or detergents that emulsify oils and aid in microbial removal from surfaces or skin.

Germ Theory of Disease

Concept, demonstrated by Louis Pasteur, that most diseases are caused by microscopic organisms.

Antibiotics

Natural antimicrobial agents produced by microorganisms, e.g., penicillin from Penicillium notatum.

Antimicrobials (antimicrobics)

Synthetic chemical agents used to treat bacterial infections.

Zone of Inhibition

Clear area around an antibiotic disk where bacterial growth is prevented.

Concentration Gradient

Decreasing antibiotic concentration radiating outward as the drug diffuses through agar.

Minimum Inhibitory Concentration (MIC)

Lowest antibiotic concentration that prevents visible growth; lies at outer edge of the inhibition zone.

Disk Diffusion Test (Kirby-Bauer Test)

Standard assay that measures antimicrobial effectiveness by comparing zone diameters on agar.

Susceptible (in AST)

Descriptor for bacteria inhibited by an antibiotic, producing a clear zone on the plate.

Resistant (in AST)

Descriptor for bacteria unharmed by an antibiotic, allowing growth up to the disk edge.

RapID ONE Panel

Cost-effective manual system that provides 18 biochemical test results simultaneously to yield a 7-digit identification code.

Fluid Thioglycollate Medium

Liquid medium that supports growth of anaerobic and microaerophilic bacteria.

Anaerobic Jar

Sealed container used to generate anaerobic, microaerophilic, or CO₂-rich conditions for culturing bacteria.

Aerotolerance

An organism’s ability or inability to live in the presence of oxygen.

Obligate (strict) aerobe

Microbe that requires oxygen for respiration; grows at the top of thioglycollate medium.

Facultative anaerobe

Organism that grows with or without oxygen, using O₂ if it is available.

Obligate (strict) anaerobe

Microbe that grows only in the absence of oxygen; found at the bottom of thioglycollate medium.