Chemical Methods of Microbial Control

A set of 70 vocabulary flashcards covering chemical methods of microbial control from the provided lecture notes.

Chemical Methods of Microbial Control

Overview of using chemical agents to kill or inhibit microorganisms.

Phenols

Disinfectants that destroy plasma membranes and denature proteins.

Phenolics

Chemical derivatives of phenol used as disinfectants; more stable and persistent with organic matter.

Phenol (carbolic acid)

First disinfectant used by Lister; skin irritant with strong odor; also used as local anesthetic.

Cresols

Phenol derivatives derived from coal tar; found in products like Lysol.

Biphenols

Phenol derivatives such as p-HisoHex; effective against gram-positive cocci; used in nurseries.

p-HisoHex

A biphenol disinfectant; excessive use in infants may cause neurological damage.

Xylenols

Phenol derivatives used in laboratories and hospitals.

Orthophenylphenol

Phenol derivative used as a disinfectant in labs and hospitals.

Lister

Pioneer who popularized phenol as a disinfectant.

Iodine

Halogen antiseptic that denatures proteins by iodination; stains skin.

Tincture of iodine

Alcohol-based solution containing iodine; early antiseptic.

Iodophors

Iodine-containing compounds that release iodine slowly; used as skin antiseptic; not effective against endospores.

Betadine

Commercial iodophor antiseptic containing iodine.

Isodine

Iodine-containing antiseptics (iodophors).

Chlorine

Halogen disinfectant forming hypochlorous acid in water; used for water disinfection; inactivated by organic matter.

Hypochlorous acid

HOCl; main active chlorine-based disinfectant; powerful antimicrobial agent.

Sodium hypochlorite

Active ingredient of household bleach; broad-spectrum disinfectant.

Chloramines

Chlorine-ammonia compounds; less effective germicides.

Ethanol

Alcohol that kills bacteria and fungi by denaturing proteins; evaporates leaving no residue.

70% Ethanol

Optimal ethanol concentration for disinfection; water aids penetration and protein denaturation.

Isopropanol

Rubbing alcohol; more effective and cheaper than ethanol for disinfection.

Alcohols

Group of disinfectants that denature proteins and disrupt membranes; do not kill spores.

Heavy metals

Metal ions with antimicrobial action at low concentrations; bind proteins and disrupt enzymes.

Oligodynamic action

Action of very small amounts of certain heavy metals with strong antimicrobial effects.

Silver

Silver ions and compounds used as antimicrobials; historically used to prevent eye infections.

Silver nitrate

1% silver nitrate used to prevent gonorrheal ocular infections in infants.

Mercury

Mercury compounds used as skin disinfectants and antiseptics.

Merthiolate

Mercury-containing antiseptic (thimerosal family) for skin application.

Mercurochrome

Mercury-containing antiseptic for skin use.

Copper

Copper compounds used to kill algae; copper sulfate used in pools and aquariums.

Copper sulfate

Algae killer in water bodies such as pools and fish tanks.

Selenium

Kills fungi and their spores; used in dandruff shampoos.

Zinc

Zinc salts used as antifungal agents; zinc chloride in mouthwashes; zinc oxide in paints.

Zinc chloride

Zinc salt used in mouthwashes and dental products.

Zinc oxide

Antifungal agent used in paints and coatings.

Quaternary ammonium compounds

Cationic surfactants that disrupt membranes and denature proteins; broad antimicrobial action.

Benzalkonium chloride

A common quaternary ammonium compound used as a disinfectant.

Cetylpyridinium chloride

Quat used as a disinfectant; found in some mouthwashes and sprays.

Zephiran

Brand name for benzalkonium chloride.

Aldehydes

Reactive molecules that inactivate proteins and nucleic acids by crosslinking.

Formaldehyde

Gaseous or 37% formalin; excellent disinfectant; mucous irritant; used in embalming.

Formalin

37% formaldehyde solution; used to preserve specimens and in vaccines.

Glutaraldehyde

Less irritating than formaldehyde; sterilizing agent for medical instruments.

Cidex

Commercial glutaraldehyde sterilizing/disinfection solution.

Sterilizing gases

Gaseous sterilizers used in specialized chambers to sterilize equipment.

Ethylene oxide

EtO; highly penetrating gas sterilant; kills all microbes including endospores; toxic/explosive.

Ozone

Oxidizing agent used with chlorine to disinfect water; more effective but less stable.

Hydrogen peroxide

Antiseptic; not ideal for open wounds; effective on surfaces and instruments; sporicidal at higher temps.

Benzoyl peroxide

Used in acne medications; antimicrobial and oxidizing agent.

Crystal violet

Dye active against gram-positive bacteria and fungi; used in solutions and ointments.

Malachite green

A dye with antimicrobial properties used in medical contexts.

Acriflavine

Yellow acridine dye used as an antiseptic.

Proflavine

Acridine dye used as an antiseptic.

Acridine dyes

Group of dyes used as antiseptics (e.g., acriflavine, proflavine).

Sorbic acid

Preservative with antifungal activity in foods (cheeses, etc.).

Sorbates

Sorbate salts (potassium, calcium) used as preservatives.

Sodium benzoate

Preservative with antifungal properties used in foods and medicines.

Propionic acid

Preservative with antifungal activity; used in breads and cheeses.

Calcium propionate

Preservative to prevent mold growth in bread.

Propionates

Propionate salts used as preservatives.

Sulfur dioxide

Preservative to prevent browning and mold in wines and dried fruits; can affect health.

Sulfites

Preservatives that can destroy vitamins and may trigger asthma; widely used in foods.

Benzoic acid

Preservative with antifungal properties in foods.

Sodium diacetate

Preservative with antifungal activity used in breads.

Nitrates

Preservatives that inhibit Clostridium botulinum in cured meats.

Nitrites

Sodium nitrite used to preserve meats; forms nitric oxide that cures color.

Nitrosamines

Carcinogenic byproducts formed from nitrites in some foods.

Surfactants

Compounds that lower surface tension; include soaps and detergents; aid cleaning.

Soap

Mechanically remove microbes by scrubbing and emulsifying oils; weak antiseptic.

Detergents

Modern surfactants; emulsify oils and improve cleansing; some have limited germicidal activity.

Nonionic detergents

Detergents with little to no antimicrobial activity but good cleaning power.

Anionic detergents

Detergents with antifungal/sanitizing properties in certain applications.

Cationic detergents

Detergents with positive charge (quats) that can be antimicrobial.

Amphoteric detergents

Detergents with both anionic and cationic characteristics; highly active disinfectants.