acetogenic bacteria - bacteria capable of reducing CO2 to acetic acid or converting sugars quantitatively into acetate.
acid-fast organisms - microorganisms (eg. mycobacteria) that resist decolorization by acid-alcohol washes that are used to remove basic stains
acidophile- A microorganism that grows best under acid conditions (down to a pH of 1).
adventitious agent – Acquired, accidental contaminants
actinomycete- a nontaxonomic term applied to a group of high G + C base composition, Gram-positive bacteria that have a superficial resemblance to fungi. Includes many but not all organisms belonging to the order Actinomycetales.
aerobic- (i) Having molecular oxygen as a part of the environment. (ii) Growing only in the presence of molecular oxygen, as in aerobic organisms. (iii) Occurring only in the presence of molecular oxygen, as in certain chemical or biochemical processes such as aerobic respiration.
aerophobic - an organism harmed by oxygen; an obligate anaerobe.
aerosol - Air suspension of solid or liquid particles having a volume median diameter of less than 50 µm. The small size of the droplets or particles allows entry to the body via the respiratory tract and readily contaminates clothing, skin and eyes.
aerotolerant anaerobes- Microbes that grow under both aerobic and anaerobic conditions, but do not shift from one mode of metabolism to another as conditions change. They obtain energy exclusively by fermentation.
agar- Complex sulfated polysaccharide derived from certain marine algae (normally red algae) that is a gelling agent for solid or semisolid microbiological media. Agar consists of about 70% agarose and 30% agaropectin. Agar can be melted at temperature above 100ºC; gelling temperature is 40-50ºC. Agar is used for performing viable counts. See also media.
airborne concentration - The amount of particles per unit volume of air. Typically this refers to the number concentration of spray drops
air changes – a value indicating the number of times per hour the air is changed within a certain room or containment. It is a test that indicates how often a cleanroom purges itself.
air sample - the collection a sample of air; can be physical (the collection and estimation of the number of airborne particles, normally called particle counting) or viable (the estimation of the number of viable micro-organisms are either deposited onto a settle plate - passive sampling - or collected from a defined volume of air - active / volumetric air-sampling using an air-sampler.
air lock - an intermediate room used to minimize the transfer of contamination from one area to another. It is often at a different air pressure to the surrounding areas.
Air velocity - a value indicating the speed of the air movement in a cleanroom or clean zone. It is an indicator of the ability of a unidirectional-flow cleanroom to purge itself.
alkalophile – a micro-organism that lives in alkaline conditions (growth range pH8.5-12.0)
anaerobic- (i) Absence of molecular oxygen. (ii) Growing in the absence of molecular oxygen, such as anaerobic bacteria. (iii) Occurring in the absence of molecular oxygen, as a biochemical process.
antagonistic – a micro-organism that limits or precents the growth of another organism.
antibiotic - substances produced by the natural metobolic processes of microorganisms that can inhibit or destroy other microorganisms
antimicrobial agent - a chemical that kills or inhibits the growth of microorganisms e.g. a disinfectant
antiseptics - chemical agent used on exposed body surface to destroy or inhibit vegetative pathogens. It is the alternative name for sanitiser as in 'hand sanitiser'. The process of using such an agent is called antisepsis.
API - Analytical Profile Index - the primary method for bacterial (and some fungal) identification based on a series of individual biochemical tests, the positive and negative reactions to which form a profile which is matches for similarity against a database.
ascomycetes- A class of fungi characterised by endogenous production of spores (asocspores) in the organ of the meiosis (ascus).
asepsis - absence of microorganisms that cause disease; freedom of infection; exclusion of microorganisms
aseptic technique- manipulating sterile instruments, equipment or culture media in such a way as to avoid contamination.
At rest – a term for the static state e.g. an at-rest cleanroom is a cleanroom that is complete, with all services operating but without personnel present.
autoclave - An apparatus for sterilizing objects (destruction of microorgaisms by high temperature) by the use of steam under pressure.
autotroph – an organism that uses inorganic carbon as its sole source of carbon.
auxotroph - an organism which cannot grow on a ‘minimal’ medium (e. g., mineral salts and glucose) without addition of one or more specific supplements (e. g., a specific amino acid).
bacillus- (L.. "little rod").Bacterium with an elongated, rod shape. A genus of bacteria of the family Bacillaceae, including large aerobic or facultatively anaerobic, spore-forming, rod-shaped cells. The term bacilli can refer to rod shaped bacteria of any genera.
bacteria- All prokaryotes that are not members of the domain Archaea. [Archaea- Evolutionarily distinct group (domain) of prokaryotes consisting of the methanogens, most extreme halophiles and hyperthermophiles, and Thermoplasma]. They are single celled organisms.
Bacterial Endotoxin Test – this is a pharmacopeial test for the detection of Gram-negative endotoxins using the LAL methodology.
bactericidal - having the characteristic of destroying bacteria
bactericide - An agent that kills bacteria. See microcidial.
bacteriostat - a chemical or physical agent that inhibits the growth of, but is not lethal to bacteria.
bacteriostatic - From the Greek words Stasis and static means to stand still. A bacteriostatic agent prevents the growth of bacteria on tissue or on objects in the environment. Some disinfectants have bacteriostatic properties (as opposed to bactericidal).
basal medium -A(n) (unsupplemented) medium which allows the growth of many types of microorganisms which do not require any special nutrient supplements, e.g. nutrient broth.
baseline – observations or data used for comparison or as a control
batch culture –a microbial laboratory culture grown in a fixed volume of growth medium; designed to produce the maximum density.
benthos – micro-organisms living at the bottom of an aquatic system, associated with sediments.
bioburden – a ‘catch all phrase’ that refers to the total microbial load of a sample or system. It normally infers unwanted contamination but can refer to the ‘natural bioburden’ or a substance.
bioburden assay – an alternative name for a dilution series or test designed to enumerate the microbial content of a sample.
Biological Indicator - a device used to validate items being sterilized through a sterilization procedure and to monitor adequacy of sterilization. The device consists of a known number of microorganisms (usually bacterial spores), of known resistance to the mode of sterilization, in or on a carrier and enclosed in a protective package. Subsequent growth or failure of the microorganisms to grow under suitable conditions indicates the adequacy of sterilization.
biofilm- Microbial cells encased in an adhesive, usually a polysaccharide material secreted by the community, and attached to a surface. They have complex structural and functional characteristics. Biofilms have physical/chemical gradients that influence microbial metabolic processes. They can form on inanimate devices (e.g. pipes) and also cause fouling (e.g. water systems). Often occurs at a physical e.g. water – solid interface.
bioluminescence- light produced by living organisms
biomass – the total mass of all living organisms, or set of organisms, usually expressed as a dry weight.
biome – a community of micro-organisms living within an ecosystem.
biota – living organisms.
biosafety cabinet – another term for microbiological safety cabinet.
centrifugal air sampler – one of two commonly use viable air-samplers. It collects micro-organisms suspended in air through centrifugal forces which ‘forces’ micro-organisms out of the air stream and onto microbiological media. See impaction air-sampler.
CFR – Code of Federal Regulations. US regulations. Parts 210 and 211 apply to biologics.
Chemostat – a growth chamber that keeps a bacterial culture at a specific volume and rate of growth by limiting nutrient medium and removing spent culture.
chemotaxis – response of motile micro-organisms, by movement towards or away from, a chemical source.
CIP – Clean-in-place. A way to clean large vessels (tanks, piping and associated equipment) without moving them or taking them apart, using high pressure rinsing equipment. Sometimes followed by SIP (steam-in-place) sanitisation steps.
Clarify – a process whereby a liquid is cleared of particles or micro-organisms by filtration or centrifugation.
classification- (i) Arrangement of organisms into groups based on mutual similarity or evolutionary relatedness.
cleanroom - a room in which the concentration of airborne particles is controlled to a defined standard. This is achieved by controlling the introduction, formation and retention of particles.
clean zone – a defined space within a cleanroom where the concentration of airborne particles is controlled. Often this is to a higher standard than the cleanroom.
coagulase - an enzyme that induces blood clotting; it is characteristically produced by pathogenic staphylococci.
coccoid - sphere-shaped
coccus- Spherical bacterial cells
coliform- Gram-negative, nonspore-forming facultative rod that ferments lactose with gas formation with 48 hours at 35ºC. Often an indicator organism for fecal contamination of water supplies. Escherichia coli and Enterobacter are important members
column – a vertical, cylindrical container or vessel used in separation processes including extraction, distillation or chromatography.
colonization - multiplication of a microorganism after it has attached to host tissues or other surfaces.
colony - a cluster or assemblage of microorganisms growing on a solid surface such as the surface of an agar culture medium; the assemblage often is directly visible, but also may be seen only microscopically.
colony forming untit (CFU) - Colony forming units. Viable micro-organisms (bacteria, yeasts & mould) capable of growth under the prescribed conditions (medium, atmosphere, time and temperature) develop into visible colonies (colony forming units) which are counted. The term colony forming unit (CFU) is used because a colony may result from a single micro-organism or from a clump / cluster of micro-organisms. It is normally expressed as CFU per g or mL.
community- All organisms that occupy a common habitat and interact with one another
contact plate - see RODAC (see later)
contaminant – a foreign agent not introduced as part of processing, such as airborne particulates or adventitious micro-organisms.
contaminated - possessing infectious organisms or substances
culture- Population of microorganisms cultivated in an artificial growth medium. A pure culture is grown from a single cell; a mixed culture consists of two or more microbial species or strains growing together
culture collection - this refers to the storage and preservation of pure cultures of microorganisms on suitable survival media. Such microrganisms are normally stored by cryopreservation (<-70oC). There are several international culture collections from which typed strains of pure microorganisms are purchased (for example, the American Type Culture Collection - ATCC - or the UK National Typed Culture Collection - NTCC.
culture medium - an aqueous solution of various nutrients suitable for the growth of microorganisms. See media.
decimal reduction time (D or D value) The time required to kill 90% of the microorganisms or spores in a sample at a specified temperature.
decontamination - to make safe by removing or reducing contamination by infectious organisms or other harmful substances. It does not imply that all micro-organisms have been eliminated to zero count.
degradation – loss or reduction of quality, integrity or character; or a reaction that breaks something down into smaller parts.
depyrogenation – the process for the removal of pyrogenic substances, normally using chemical or thermoetric processes. It is measured using Gram-negtaive endotoxin as a heat resistant challenge but the process refers to the removal of all pyrogens,
detergent - an organic molecule, other than a soap, that serves as a wetting agent and emulsifier; it is normally used as cleanser, but some may be used as antimicrobial agents
differential medium- Cultural medium with an indicator, such as a dye, which allows various chemical reactions to be distinguished during growth. The medium allows growth of several microbes but creates different appearances. An example is MacConkey agar.
diluent – a chemically inert substance added to a solution to increase the volume and to reduce the concentration; a diluting agent.
dilution plate count method- Method for estimating the viable numbers of microorganisms in a sample. The sample is diluted serially and then transferred to agar plates to permit growth and quantification of colony-forming units
direct count- Method of estimating the total number of microorganisms in a given sampl by direct microscopic examination
direct inoculation - the secondary sterility test method and a crude technique to examine for microbial growth by transferring a portion of a liquid or solid into a broth media, incubating for a defined time, and then examining for observable growth.
discrete particle counter - alternative name for a particle counter.
disinfectant - an agent that kills all growing or vegetative forms of microorganisms, thus completely eliminating them from inanimate objects.
disinfection - refers to the use of a physical process or a chemical agent (such as disinfectants) to destroy vegetative pathogens but not necessarily bacterial endospores
domain – a major taxonomic assemblage
doubling time - the time needed for a population to double.
DQ – design qualification. A documented review of the design, at appropriate stages of a project, for conformance to operational and regulatory expectations.
dynamic state – refers to environmental or particle monitoring where a room is occupied (in less politically correct times this was called the ‘manned state’).
dynamic contamination - occurs when organisms are actively metabolising. The numbers are increasing (10E4 or >) and the organism is usually a Gram-negative bacterial species. Only the dynamically contaminated product can be spoiled.
ecosystem – a self-regulating biological community in a defined habitat
efficacy – the ability of a substance (e.g. chemical disinfectant) to produce a desired effect (e.g. reduction in bacterial numbers) under different conditions.
elution – washing out; removal of material; the separated material is the eluate.
emulsification – a process that creates a stble mixture of two solutions that would not normally mix together (such as oil and water) by forcing one to disperse with the other as droplets.
endemic species – micro-organisms restricted to a certain location
endogenous – growing or developing from within a micro-organism
endospore- Differentiated cell formed within the cells of certain Gram-positive bacteria and extremely resistant to heat and other harmful agents. Sometimes simplified to 'spore'.
endotoxin - a toxin, from the outer cell membrane of Gram-negative bacteria, consisting of heat stable lipopolysaccharide (LPS) molecules. It is normally released by cell lysis. Can cause septic shock and tissue damage in people.
environmental monitoring – a documented series of sampling and testing in controlled environments in order to demonstrate conformance to a series of pre-set limits or for trends. It is distinct from environmental control.
enrichment culture- Technique in which environmental (including nutritional) conditions are controlled to favour the development of a specific organism or group of organisms.
enriched media - A medium which ensures growth of a particular microbe. An example is blood agar
Enterobacteriaceae / enteric bacteria- General term for a group of bacteria that inhabit the intestinal tract of humans and other animals. Among this group are pathogenic bacteria such as Salmonella and Shigella and consists of members of the family Enterobacteriaceae (gram-negative, peritrichous or nonmotile, facultatively anaerobic, straight rods with simple nutritional requirements).
excipient – a raw material that is present in a drug product and thus has direct patient contact. Includes bulking agents, stabilising agents, preservatives, salts, solvents or waters.
exogenous – developing from the outside; can include external factors that affect the growth or survival of a micro-organisms, such as light, humidity, nutrients etc.
exotoxins - poisonous substances produced by the microbial cell and liberated into the surrounding environment, without destruction of the cell.
exponential growth- Period of sustained growth of a microorganism in which the cell number constantly doubles within a fixed time period.
exponential phase- Period during the growth cycle of a population in which growth increases at an exponential rate. As referred to as logarithmic phase
extractables – substances that are withdrawn from a container or closure through a process.
extreme environment – an environment in which physicochemical factors (e.g. pH, temperature, salinity etc.) are outside of the normal range for most micro-organisms
extremophiles - microorganisms that grow under harsh or extreme environmental conditions such as very high temperatures or low pHs.
f-value - the time required to reduce the total number of micro-organisms in a certain medium to a required level.
facultative organism- Organism that can carry out both options of a mutually exclusive process (e.g., aerobic and anaerobic metabolism).
FDA-483 – a form prepared by at the conclusion of an inspection by the Federal Drug Administration (FDA), which cite observations that may constitute violations of federal law (in the opinion of the inspector).
filamentous- In the form of very long rods, many times longer than wide (for bacteria), in the form of long branching strands (for fungi).
filter – a porous material through which a liquid or gas is passed so that particulates and impurities and micro-organisms are held in suspension. Some ‘impurities’ will pass through depending upon the filter size, viscosity, concentration and so on. The part of the mixture that passes through is the filtrate.
filtration rate – the volume of solution cleared of particles per unit time.
fimbria (plural, fimbriae)- Short filamentous structure on a bacterial cell; although flagella-like in structure, generally present in many copies and not involved in motility. Plays a role in adherence to surfaces and in the formation of pellicles
flagellum (plural, flagella)- Whiplike tubular structure attached to a microbial cell responsible for motility
fluorescent- having the ability to emit light of a certain wavelength when activated by light of another wavelength
FMEA – Failure Modes Evaluation and Analysis (or Failure Mode and Effects Analysis). A risk assessment and risk mitigation tool. Similar to HACCP.
formulation – the method and process for selecting the components of a mixture, including the active ingredients, to make the form that the drug is finally administered in (such as a tablet or injection)
fractional sterilization - a method of sterilization that involves alternating exposure and cooling time for a consecutive period.
fruiting body- Macroscopic reproductive structure produced by some fungi, such as mushrooms, and some bacteria, including myxobacteria. Fruiting bodies are distinctive in size, shape, and coloration for each species
fumigant- liquid or solid chemical that forms vapours that kill organisms.
fungicide- chemical or physical agent that kills or inhibits development of fungus spores or mycelium. The term 'fungicide' includes all preparations intended for preventing, destroying, repelling or mitigating any fungi.
fungistasis- Suppression of germination of fungal spores or other resting structures in natural soils as a result of competition for available nutrients, presence of inhibitory compounds, or both.
fungistasis- The prevention of fungal growth; the effect is reversible, if the inhibitor is removed or diluted, growth is resumed.
fungistatic - Able to inhibit germination of fungus spores or development of mycelium without causing death of fungus.
fungus (plural, fungi)- Nonphototrophic, eukaryotic microorganisms that contain rigid cell walls. An example of micro-scopic fungi are yeasts and molds and macroscopic fungi are mushrooms, puff balls and bracket fungi. All fungi are heterotrophic; living off of organic substrates (dead animal/plant material), or on the tissue of other organisms (parasite). Their reproduction is primarily through spore formation.
general purpose media - Medium to grow as wide a variety of microbes as possible. An example is TSA
generation time – the time required for a microbial population to double in number
genotype- Precise genetic constitution of an organism.
genus (plural, genera)- The first name of the scientific name (binomial); the taxon between family and species
Geobacillus stereathermophillus - a highly heat-resistant, endospore-forming microorganism used in form on commercially prepared spore strips for checking sterilization effectiveness in steam sterilizers.
germination - the stage following bacterial endospore activation in which the endospore breaks its dormant state. Germination is followed by outgrowth.
glucans - polysaccharides composed of glucose units held together by glycosidic linkages. Some types of glucans have a(1_3) and a(1_6) linkages and bind bacterial cells together on teeth forming a plaque ecosystem. Can cause a positive response in the LAL assay and can therefore sometimes be mistaken for endotoxin.
glycocalyx - the means by which a microbial community adheres as a biofilm. It is a coating of macromolecules which protects some kinds of bacteria. It helps bacteria adhere to its environment. It can differ in thickness, organization and chemical composition. Two types are slime layer and capsule
Good Manufacturing Practice (GMP) and current Good Manufacturing Practice (cGMP) – standards which relate to the manufacturing of biopharmaceuticals and blood products. Include SOPs to be followed; processes to be validated; equipment to be qualified; staff to be trained; and a clean environment to be maintained.
Gram-negative cell - a bacterial cell whose cell wall contains relatively little peptidogylcan but has an outer membrane composed of lipopolysaccharide, lipoprotein, and other complex macromolecules. Gram-negative and positive micro-organisms are distinguished using the Gram stain. Gram-negative micro-organisms do not retain the primary stain (crystal violet) and require counter-staining.
Gram-positive cell - a bacterial cell whose cell wall consists mainly of peptidogylcan and lacks the outer cell membrane found on Gram-negative cells. Gram-positive micro-organisms retain the primary stain (crystal violet).
Gram’s stain- Differential stain that divides bacteria into two groups, Gram-positive and Gram-negative, based on the ability to retain crystal violet when decolorized with an organic solvent such as ethanol. The cell wall of Gram-positive bacteria consists chiefly of peptidoglycan and lacks the outer membrane of Gram-negative cells. The Gram-stain is the basis of bacterial identification. Gram-negative and positive micro-organisms are distinguished using the Gram stain.
growth rate- The rate at which growth occurs, usually expressed as the generation time
GXP – All-inclusive term for Good Clinical Practice, Good Laboratory Practice and Good Manufacturing Practice.
habitat- the place where an organism lives. The habitat typically contains all the conditions to either simulate growth or to preserve the organism.
halophile- Organism requiring or tolerating a saline environment
Hazard Analysis and Critical Control Points (HACCP) - a method of determining the hazards in a process and to control them.
HEPA - High Efficiency Particulate Air - describes the system for filtering (diluting) air into cleanrooms. Standard HEPA filters remove 99.97% of 0.3m particles.
heterotroph- Organism capable of deriving carbon and energy for growth and cell synthesis from organic compounds; generally also obtain energy and reducing power equivalents from organic compounds.
holoplanktonic – micro-organisms found in a water system for most of the year
HVAC - Heating, Ventilation and Air Conditioning - a system for providing air into clean rooms and controlling their classification by removing airborne particles through the use of HEPA filters.
hydrology – the study of the inflow and outflow of water
hydrophilic – having an affinity for water; dissolving in water
hydrophobic – insoluble in water; resisting or repelling water
hypha (pl., hyphae) - the unit of structure of most fungi and some bacteria; a tubular filament.
impaction air-sampler – one of two commonly used air-samplers. Air is drawn into an air-sampler and impacts onto the surface of a culture medium . The force of the impaction will deposit any micro-organisms onto the agar surface. See centrifugal air-sampler.
incubation - the process of maintaining appropriate conditions (temperature, humidity, time) to allow microbial cells to replicate.
indicator organism - an organism whose presence indicates the condition of a substance or environment, for example, the potential presence of pathogens. This is sometimes called a 'specified' or 'objectionable' microorganism and they are examined for in raw materials and in some water samples. For example, in water, coliforms are used as indicators of faecal pollution.
infection - invasion of the body by pathogenic microorganisms, and the reaction of tissues
in-house – work conducted in the laboratory; not out sourced
inoculate- To transfer a liquid, product or micro-organism from one container or agar medium to another. See 'direct inoculation'.
inoculum- Material used to introduce a micro-organism into a suitable situation for growth
intermediates / in-process – substances formed or parts of the middle of a process that make up a series of processing steps between raw materials and the final products.
in vitro- Literally "in glass"; it describes whatever happens in a test tube or other receptacle, as opposed to in vivo. When a study or an experiment is done outside the living organism, in test tube, it is done in vitro.
in vivo- In the body, in a living organism, as opposed to in vitro; when a study or an experiment is done in the living organism, it is done in vivo
isokinetic – the taking of a sample where the air entering the sampler is at the same velocity and direction as the air in the cleanroom (isoaxial sampling). The opposite term is anisokinetic.
isolation- Any procedure in which an organism present in a particular sample or environment, is obtained in pure culture.
Isolator – Self-contained clean spaces designed to protect product from contamination by room, that exchange air with the surrounding environment only if the air has passed through a filter of at least HEPA quality.
IQ – installation qualification. Documented verification that aspects of a facility, utility or equipment meet approved specifications and have been correctly installed.
lag phase - the early period of growth undergone by a microbial cell. Growth is slow following inoculation into a culture medium. See logarithmic phase.
Laminar Airflow - where air travels in either a vertical or horizontal direction at the same velocity.
LAF / LAC - Laminar airflow cabinets are designed to direct particles away from the work surface (this is often supported by airflow or smoke studies). The term 'LAF' is becoming increasingly replaced by UDAF or uni-directional air-flow. Thee terms have different meanings (see UDAF and turbulent flow below)
latent phase – the period following the introduction of micro-organisms into a fresh culture medium when there is no increase in biomass or population count.
leachable – chemical entity that has the potential to be extracted from a container or closure when exposed to certain conditions or solutions.
Limulus amebocyte lysate - LAL, the biochemical method used for the Bacterial Endotoxin Test. There are three methods: gel-clot, turbidimetric and chromogenic, based on an extract of the blood of the crab Limulus polyphemus.
lipopolysaccharide (LPS)-Complex lipid structure containing unusual sugars and fatty acids found in many Gram-negative bacteria. It is the basis of endotoxin.
logarithmic (log) phase - the stage of active microbial cell division.
lyophilization – freeze-drying; a procedure by which a liquid solution is frozen to a glassy slate (primary drying), then slightly heated to remove unfrozen water by sublimation.
lysis- A breakdown or dissolution of cells resulting in loss of cell contents.
medium (plural, media)- Any liquid or solid material prepared for the growth, maintenance, or storage of microorganisms
media simulation trial (or broth filling trial) – the exposure of microbiological growth medium to product contact surfaces, container closure systems, critical environments and process manipulations to closely simulate the exposure that product itself will undergo.
membrane filter technique The use of a thin porous filter made from cellulose acetate, celulose nitrate or some other polymer (normally 0.45m) to collect microorganisms from a liquid or air sample. It is the primary sterility testing method.
menstrumm – a solvent (as in a raw material).
mesophile- Organism whose optimum temperature for growth falls in an intermediate range of approximately 15 to 40ºC
microaerophile- Organism that requires a low concentration of oxygen for growth. Sometimes indicates an organism that will carry out its metabolic activities under aerobic conditions but will grow much better under anaerobic conditions
microbial population- Total number of living microorganisms in a given volume or mass.
microbicide
• The root -cide meaning to kill can be combined with other terms to define an antimicrobial agent aimed at destroying a certain group of microorganisms.
• Bactericide is a chemical that destroys bacteria except for those in the Endospore stage.
• Fungicide is a chemical that can kill fungal spores, hyphae, and yeast.
• Virucide is any chemical known to inactivate viruses, especially on living tissue.
• Sporicide is an agent capable of destroying bacterial endospores .
microbiology- Study of microorganisms
microenvironment – a small-scale habitat within a general ecosystem
micron – a micrometre (1/100th of a millimetre or 1/1,000,000th of a metre)
microorganism - a microscopic organism consisting of a single cell or cell cluster including the viruses.
microcosm- A community or other unit that is representative of a larger unity.
microenvironment- Immediate physical and chemical surroundings of a microorganism
microflora- Bacteria (including actinomycetes), fungi, algae, and viruses found in a given location. For the human body (and related to this, the majority of the micro-organisms found in the Aseptic Filling Suite), the term Normal Flora can be applied. It can also called resident flora and consists of a variety of microorganisms adapted to the body at the sites of the human body that harbor normal flora are skin, digestive tract, upper respiratory tract, external gentiourinary tract and external surfaces of the eyes and ears. The majority of such micro-organisms isolated are Staphylococci and Micrococci.
microhabitat- Clusters of microaggregates with associated water within which microbes function. May be composed of several microsites (e.g., aerobic and anaerobic).
microorganism (microbe)- Living organism too small to be seen with the naked eye (< 0.1 mm); includes bacteria, fungi, protozoans, microscopic algae, and viruses
most probable number - the MPN statistical technique consists of a variety of dilution broths to test a material for the number of viable microorgansims where inhibition of the material on microbial growth maybe a problem. The broths are examined for the 'endpoint' (where growth no longer occurs) to estimate the microbial number. Expressed as a density or population of organisms per 100 mL of sample water
motility- Movement of a cell under its own power
mould- any of a large group of fungi that cause mould or mouldiness and that exist as multicellular filamentous colonies; also the deposit or growth caused by such fungi. Moulds typically do not produce macroscopic fruiting bodies
mushroom- Large, sometimes edible, fruiting body produced by some fungi
mycology - the science and study of fungi.
mycoplasma - A micro-organism intermediate in size between viruses and bacteria possessing many virus-like properties and not visible with a light microscope.
nomenclature- System of naming organisms
non-conformity – a deficiency in a characteristic, product specification, process parameter, record, or procedure, that renders the quality of a product, raw material or process unacceptable.
non-unidirectional air-flow – where the air supply entering a clean zone mixes with the internal air. See turbulent air.
normal flora- The micro-organisms which ordinarily grow on the various surfaces of a plant or animal.
neutrophile – micro-organism living under neutral pH conditions (pH5.5-8.5)
nutrient- Substance taken by a cell from its environment and used in catabolic or anabolic reactions
nutrient medium - a liquid broth or semi-solid jelly containing nutrients which stimulate and sustain the culture and proliferation of bacteria, higher plant cells or animal tissue.
nutritive properties - the term given to the fertility testing / growth promotion of culture media in order to demonstrate that the test medium supports microbial growth. Can include general or selective testing.
objectionable microorganism - see indicator microorgaism
obligate- (i) Adjective referring to an environmental factor (for example, oxygen) that is always required for growth. (ii) Organism that can grow and reproduce only by obtaining carbon and other nutrients from a living host, such as obligate symbiont
oligotroph- Microorganism specifically adapted to grow under low nutrient supply. Thought to subsist on the more resistant organic matter and be little affected by the addition of fresh organic materials. Sometimes a synonym for autochthonous
OOS – out-of-specification result. A result outside the range of an approved specification. An OOS must be investigated to determine whether it is due to laboratory error, process error, or operator error. A judgement is then made to determine if the result is valid or invalid.
OOT – out of tolerance, in relating to calibration; out –of –trend, in relating to unexpected results from historical or statistical trends.
OQ – operational qualification. Documented verification that all aspects of a facility, utility or equipment operate as intended through all anticipated ranges.
Organism – a single, autonomous living thing e.g. micro-organism.
particle - an object of solid or liquid composition, or both, and of a certain size. It is a small piece of matter with a defined physical boundary. The size and number of particles are critical in order to assess a cleanroom.
particle counter - a device which measures the number of airborne particles of a given size by passing a sample of air through a focused light source. The presence of a particle causes dispersion of the light and the presence of a particular size can be detected using pre-defined criteria. At BPL two sizes of particles are measures: 0.5m (a close approximation of the size of a bacterium) and 5.0m (a close approximation of the size of a human skin cell).
passage – when micro-organisms are cultured, each dilution step in vitro is one passage. Some tests will have a limit on the number of acceptable passages.
pasteurisation- Process using mild heat to reduce microbial numbers in heat-sensitive materials. This is the function of the AHT (SEC) water drenching cabinets
pathogen - an organism able to inflict damage on the host it infects. Some microorganisms isolated are potentially pathogenic and all isolated in the Microbiology laboratory are treated as potentially hazadous.
pathogenic - producing or capable of producing disease
peptidoglycan-Rigid layer of cell walls of bacteria, a thin sheet composed of N-acetylglucosamine, N-acetylmuramic acid, and a few amino acids. Also called murein. It is most prevalent in Gram-positive micro-organisms.
peptones - water-soluble digests or hydrolysates of proteins that are used in the preparation of culture media.
petri dish - a shallow dish consisting of two round, overlapping halves that is used to grow microorganisms on solid culture medium; the top is larger than the bottom of the dish to prevent contamination of the culture.
phenotype- Observable properties of an organism
phylogeny- Ordering of species into higher taxa and the construction of evolutionary trees based on evolutionary (genetic) relationships
plankton – free-floating micro-organisms e.g. bacterioplankton.
plate count- Number of colonies formed on a solid culture medium when uniformly inoculated with a known amount of sample, generally as a dilute soil suspension. The technique estimates the number of certain organisms present in a sample
population - an assemblage of organisms of the same type.
pour plate- Method for performing a plate count of microorganisms. A known amount of a serial dilution or sample is placed in a sterile Petri dish and then a melted agar medium is added and the inoculum mixed well by gently swirling. After growth the number of colony forming units, on the surface or within the agar, can be counted
PQ – performance qualification. Documented verification of a facility, utility or equipment can perform as intended in meeting pre-determined acceptance criteria.
pre-filter - a filter positioned in front of another filter (e.g. a HEPA filter) to reduce the blockage of contaminants. It will have a lower removal rating than the main filter.
prokaryote - a description for a kingdom of organisms where the members have a simple cell lacking a true nucleus, a nuclear envelope, and membrane enclosed organelles. The bacteria are members of this kingdom. The appendages of these cells provide mobility by flagella, attachment by pili and fimbriae and in some cells DNA transfer also by pili.. The cell envelope (outer covering) consists of three layers: the glycocalyx, the cell wall and the cell membrane. The composition of the cell wall determines the classification of the bacteria (gram positive, gram negative, lacking cell wall or chemically unique cell walls). Most bacteria have three general shapes: coccus(round), bacillus(rod), or spiral.
pseudomonad- Member of the genus Pseudomonas, a large group of Gram-negative, obligately respiratory (never fermentative) bacteria.
psychrophile - a microorganism that grows well at 0°C and has an optimum growth temperature of 15°C or lower and a temperature maximum around 20°C.
psychrotroph - a microorganism that grows at 0°C, but has a growth optimum between 20 and 30°C, and a maximum of about 35°C.
pure culture- population of microorganisms, which are identical and are composed of a single strain. Such cultures are obtained through selective laboratory procedures and are rarely found in a natural environment
pyogenic- Pus-forming; causing abscesses
pyrogen - fever is initiated when a circulating substance called pyrogen resets the hypothalmalic thermostat to a higher setting. Pyrogenic substances include bacterial endotoxins; extotoxins and viruses. Endotoxins are examined using the LAL test and all pyrogens can be examined using the rabbit pyrogen test.
pyrogenic - Fever-inducing
Q10- A relationship for the effect of temperature on a process such that the process rate increases by the same multiple for every 10°C rise in temperature.
qualification – Documenting that a piece of equipment does what it was designed to do. Was installed correctly, and continues to operate within specified parameters over time. The usual sequence of qualification steps is: DQ, IQ, OQ and PQ.
quiescent - Not growing.
Reverse osmosis - The term reverse osmosis comes from the process of osmosis, the natural movement of solvent from an area of low solute concentration, through a membrane, to an area of high solute concentration if no external pressure is applied.
For reverse osmosis the process involves pushing a high solute solution through a filter that traps the solute, and many micro-organisms, on one side and allows the pure solvent to be obtained from the other side. This is by applying a pressure in excess of the osmotic pressure. The membrane – a thin film composite membrane - is semipermeable (it allows the passage of solvent but not of solute).
RODAC - is the international acronym for a contact plate (that is an agar plate, with a raised surface, applied to a surface for the enumeration of microorganisms). It stands for Replicate Organism Detection And Counting.
risk assessment – a systematic process of organising information to support a risk decision. It involves the identification of hazards, analysis and evaluation of the risk associated with the exposure of the hazards. This can be quantified to the probability of occurrence of harm and the severity of that harm.
sanitation - a cleansing technique used to remove microbes or other particles by reducong the level of contamination. It does not produce total kill. Involves the use of sanitisation agents, which are chemicals/products such as soaps or detergents used as a cleaning technique to remove microorganisms and reduce the level of contaminants.
saturated steam - steam holding all the moisture it can hold and still remain a vapor.
selective medium- Medium that allows the growth of certain types of microorganisms in preference to others (by inhibiting the growth of unwanted microorganisms). For example, an antibiotic-containing medium allows the growth of only those microorganisms resistant to the antibiotic
serial dilution- Series of stepwise dilutions (in a diluent such as saline or a broth medium) performed to reduce the populations of microorganisms in a sample to manageable numbers
settle plate - an agar plate used for passive air-sampling. The plate is exposed for a fixed duration, after which it is incubated, and the number of microorganisms which have settled on it and have produced colonies are counted.
soil-Unconsolidated mineral or organic matter on the surface that has been subjected to and influenced by genetic and environmental factors of: parent material, climate (including water and temperature effects), macroorganisms and microorganisms, and topography, all acting over a period of time and producing a product--soil--that differs from the material from which it is derived in many physical, chemical, biological, and morphological properties, and characteristics
species- In microbiology, a collection of closely related strains sufficiently different from all other strains to be recognized as a distinct unit
specific epithet- Designation of a particular organism in the binomial nomenclature system. For example, coli is the specific epithet of Escherichia coli
specified microorganism - see indicator microorganism
specificity – the degree to which a substance (e.g. disinfectant) exerts a definitive and distinctive influence on a particular process or micro-organism
spirillum (plural, spirilli)- (i) Bacterium with a spiral shape which is relatively rigid. (ii) Bacterium in the genus Spirillum
sporangiospore- Spore formed within a sporangium by fungi in the phylum Zygomycota.
sporangium- Fungal structure which converts its cytoplasm into a variable number of sporangiospores; formed by fungi in the phylum Zygomycota.
spores- Specialized reproductive cell. Asexual spores germinate without uniting with other cells, whereas sexual spores of opposite mating types unite to form a zygote before germination occurs (see also endospores).
sporicidal - any agent with the ability to kill spores
spread plate- Method for performing a plate count of microorganisms. A known amount of a serial dilution is spread over the surface of an agar plate. After growth the number of colony-forming units is counted
stationary phase- Period during the growth cycle of a population in which growth rate equals the death rate.
strain - a population of organisms that descends from a single organism or pure culture isolate.
sterile - an absolute term meaning free of all living microorganisms but not necessarily any biologically reactive by-products such as exotoxins or endotoxins.
sterilization- Rendering an object or substance free of viable microbes but not of microbial toxins, such as, endotoxin by destroying or removing all viable microorganisms, including viruses. An object cannot be slightly sterile or almost sterile- it is either sterile or not sterile. Control methods that sterilize are generally reserved for inanimate objects
static state – refers to environmental or particle monitoring in a room which is unoccupied (but where equipment is operating normally). In the past this was called the ‘unmanned state’.
static contamination - occurs when a product contains non-metabolising
organisms. The numbers remain constant (<100/g) and normally represent a
wide variety of species.
streak plate - a petri dish of solid culture medium with isolated microbial colonies growing on its surface, which has been prepared by spreading a microbial mixture over the agar surface, using an inoculating loop. Somtimes this is a modification of the Miles-Misra technique.
succession- Gradual process brought about by the change in the number of individuals of each species of a community and by the establishment of new species that gradually replace the original inhabitants
supernatant – material floating on the surface of a liquid mixture or the overlying fluid that remains after the precipitation of a solid component through centrifugation.
surfactant – any substance that changes the nature of a surface, such as lowering the surface tension of water.
swab - a wad of absorbent material usually wound around one end of a small stick and used for applying medication or for removing material from an area; also, a dacron-tipped polystyrene applicator.
taxon (plural, taxa)- A group into which related organisms are classified.
taxonomy- Study of scientific classification and nomenclature.
teichoic acids- All wall, membrane, or capsular polymers containing glycerophosphate or ribitol phosphate residues
thermophile- Organism whose optimum temperature for growth is between 45 and 85ºC
total viable count - see viable count; the 'total' normally refers to the adding together of two or more tests to give the total number of micro-organisms present in a sample (for example, a fungal count on a selective agar like SDA to a bacterial count on a general agar like TSA); can be aerobic (TVAC) or anaerobic (TVAnC).
toxin – a microbial product that can cause injury to other micro-organisms.
Transmissible spongiform encepalopathies (TSE) – neurological disease in mammals, caused by prions. Some culture media is required to be theoretically free of TSEs.
turbulent air-flow – air that moves in a disorderly way and where the pathway is difficult to predict. This is often caused by air moving past an object which causes random eddies. This is opposite to laminar or unidirectional airflow.
UDAF – unidirectional air-flow. This indicates air moving in streamlines of the same direction but not necessarily at different velocities (for air moving in both the same direction and at the same velocity this is described as laminar air-flow; for air moving in different directions this is non-unidirectional or turbulent air-flow).
ULPA - ultra-low penetrating air-filter. A more advanced filter than a HEPA filter. It can reduce the number of particles in the air of 0.12 m and greater by 99.999%.
vegetative cell- Growing or feeding form of a microbial cell, as opposed to a resting form such as a spore. The vegetative cell state is the form in which an organism is able to grow and divide continuously, given favourable conditions (although this can also refer to the non-reproductive phase in fungi). Unlike endospores, vegetative cells are relatively poor at surviving environmental stresses such as high temperature and drying
viable- Alive; able to reproduce.
viable but nonculturable- Organisms that are alive but cannot be cultured on laboratory media.
viable count- Measurement of the concentration of live cells in a microbial population. There are four main methods: pour plate; spread plate; membrane filtration or most probable number. Often referred to as total viable count.
vibrio- (i) Curved, rod-shaped bacterial cell. (ii) Bacterium of the genus Vibrio
virus - an infectious agent having a simple a cellular organization with a protein coat and a single type of nucleic acid, lacking independent metabolism, and reproducing only within living host cells.
viricide – an agent that kills viruses.
VITEK - an automated microbiological identification system which detects reactions of microorganisms to a range of substrates.
Water for Injection - is the highest grade of water. It can either be sterile or as bulk. There are limits on the number of viable microorgansims and endotoxin levels.pure water, produced by distillation or reverse osmosis. WFI must meet the pharmacopoeial requirements for bioburden and endotoxin.
Demineralised water - is treated mains water where significant minerals and ions are removed. There are limits for the number of viable microorganisms.
Mains (or raw or potable water) - is the incoming water from a water authority. There are limits for the number of, and absence of certain types of, viable microorganisms
water activity (aw)- A measure of water content equivalent to percent humidity divided by 100.
wild type-Strain of microorganism isolated from nature. The usual or native form of a gene or organism
Xenobiotic- A chemical which is not a natural component of the living organism exposed to it.
Xerophile- An organism which can grow at very low moisture levels.
yeast - a unicellular fungus that has a single nucleus and reproduces either asexually by budding or fission, or sexually through spore formation.
z value - the increase in temperature required to reduce the decimal reduction time to one-tenth of its initial value. See also decimal reduction time.
Zygospore - A sexually produced resting fungal spore of the zygomycetes produced by the fusion of two morphologically similar gametangia.
