Microbiology - 001 - Streak Plating

Streaking is a technique used to isolate a pure strain from a single microorganism. Micro 201L, 302, 302L, 310L, 440

Microbiology - 002 - Serial Dilutions

Sometimes a solution of bacteria is too concentrated to work with. A serial dilution is a series of successive, measured dilutions in order to obtain a known, workable concentration of bacteria.

Microbiology - 003 - Bacterial Smear and Simple Stain

Because bacteria are, for the most part, transparent, we use stains to give them color for microscopic observation. Making a bacterial smear prepares the bacteria to be stained and a simple stain is a quick and easy way to observe bacteria.

Microbiology - 004 - Spread Plate Method

The spread plate method is a technique to plate a liquid sample containing bacteria so that the bacteria are easy to count and isolate. A successful spread plate will have a countable number of isolated bacterial colonies evenly distributed on the plate. 

Microbiology - 005 - Gram Stain

The Gram stain is a fundamental tool used to differentiate bacteria by placing them into one of two general groups. Bacteria that are a deep purple after staining are called Gram + (positive), while bacteria that appear a lighter pink are called Gram - (negative.) Becoming familiar with the Gram stain technique is essential and it is often the first step in identifying an unknown bacterium. 

Microbiology - 006 - Endospore Stain

Some bacteria produce endospores in response to stressful environmental conditions. These endospores are dormant cells that are able to survive until conditions improve, then become active and proliferate once they do. The endospore stain causes these unique structures to be easily visible and can help determine if they are present in a particular culture.

Microbiology - 007 - Carbohydrate Fermentation Test

The carbohydrate fermentation test is used to determine whether or not a bacteria can utilize a certain carbohydrate. It tests for the presence of acid and/or gas produced from the fermentation of a single particular carbohydrate.

Microbiology - 008 - Catalase Test

The catalase test tests for the presence of catalase, an enzyme that breaks down the harmful substance hydrogen peroxide into water and oxygen. If an organism can produce catalase, it will produce bubbles of oxygen when hydrogen peroxide is added to it.

Microbiology - 009 - Oxidase Test

The oxidase test determines whether or not a bacterial isolate produces the enzyme cytochrome c oxidase, which is an important part of the electron transport chain.

Microbiology - 010 - Hemolysis

Some bacteria are able to break down blood cells by a process called hemolysis. Knowing what type of hemolysis a bacterial strain is capable of can be helpful in identifying several types of bacteria, especially organisms isolated from human tissue such as Streptococcus and Staphylococcus species.