Isolation and Cultivation

Inoculation

Transfer of microorganisms into a growth medium for cultivation.

Incubation

Maintenance of inoculated cultures under conditions favorable for microbial growth.

Cultivation

Growth of microorganisms in appropriate culture media under controlled conditions.

Isolation

Process of obtaining a pure culture from a mixed microbial population.

Pure Culture

Culture containing only one microbial species with uniform characteristics.

Streak Plating

Isolation method that thins microbial populations across an agar surface using an inoculating loop.

Simple Streak

Streak plating pattern using a single continuous streaking area.

Multiple Interrupted Streak

Streak plating pattern using successive streaking sectors to dilute microbial populations.

Spread Plating

Isolation and enumeration method in which a diluted sample is spread across the agar surface.

Pour Plating

Isolation and enumeration method in which a sample is mixed with molten agar before solidification.

L-Rod

Glass or plastic spreading tool used in spread plating.

Colony Morphology

Visible characteristics of microbial colonies growing on solid media.

Surface

Appearance of a colony's outer surface.

Shiny

Reflective colony surface appearance.

Smooth

Even colony surface lacking irregularities.

Veined

Colony surface marked by vein-like patterns.

Rough

Uneven or coarse colony surface appearance.

Dull

Non-reflective colony surface appearance.

Wrinkled

Colony surface containing folds or ridges.

Powdery

Colony surface resembling fine powder.

Texture/Consistency

Physical appearance or feel of a microbial colony.

Dry

Colony texture lacking visible moisture.

Moist

Colony texture appearing wet or hydrated.

Mucoid

Colony texture characterized by abundant extracellular slime.

Viscous

Colony texture exhibiting a sticky consistency.

Pigmentation

Visible coloration produced by microbial colonies.

Opacity

Degree to which a colony blocks light transmission.

Translucency

Partial transmission of light through a colony.

Cloudy

Hazy colony appearance caused by incomplete light transmission.

Iridescent

Colony appearance displaying changing colors depending on light angle.

Diffusible Pigments

Pigments released by microorganisms into the surrounding medium.

Colony Diameter

Measurement of colony width expressed in millimeters.

Flocculent Growth

Broth growth pattern characterized by suspended clumps of cells.

Uniform Turbidity

Broth growth pattern in which cells are evenly dispersed throughout the medium.

Sediment

Broth growth pattern characterized by cell accumulation at the bottom of the tube.

Pellicle

Broth growth pattern characterized by growth at the liquid-air interface.

Aseptic Technique

Practices and procedures that minimize contamination during microbiological work.

Disinfection

Reduction of microorganisms on surfaces using chemical agents.

Flame Sterilization

Use of direct heat to destroy microorganisms on laboratory instruments.

Inoculating Loop

Wire tool used for transferring microorganisms between media.

Agar Plate

Flat culture vessel containing solidified agar medium.

Agar Stab

Deep inoculation of semi-solid or solid medium used to evaluate growth characteristics such as motility.

Agar Slant

Agar medium solidified at an angle inside a test tube.

Broth Culture

Liquid culture medium used for microbial growth and propagation.