MicroReview - Module 6 Aseptic Transfer

Define Aseptic technique  

A set of procedures used to prevent contamination

List the procedures for Aseptic transfer

Light your bunsen burner 

Flame the inoculating loop, moving it from base (until red hot) to loop until the entire wire is red hot

Cool the inoculation loop for about 30 seconds

Using your open hand, pick up the stock culture tube and fresh tube and hold them in a v-shape. 

With your pinky, uncap the the tube nearest to your hand then the other without the edges touching your hand

Flame the top edges of the tube by rolling them into the fire.

Use your inoculating loop to obtain the microbe from the stock culture 

• Dip the end of the loop in broth 

• Flat surface up, touch the growth of the slanted agar to remove  

Insert the inoculation loop and inoculum into the fresh tube

Re-flame the the rims of both tubes and re-cap the tubes

Re-flame the inoculation loop until red hot all over 

Turn off the flame 

Take the tube for incubation at 37 celsius

List three potential contaminants during aseptic transfer

Microbes are everywhere, thus contamination can come from anywhere. Three of which include:

• The Air 

• Your hands

• Your lab counter  

Why do we flame our inoculating loop from base to loop instead of the other way?

It prevents microbes on the loop from splattering out into the air due to the heat. 

Define Aseptic

Aseptic refers to lack of contamination. 

What does the prefix ‘a-‘ or ‘an-‘ mean?

It indicates something without. The absence of something. 

• Example Anaerobic refers to something that deals with no oxygen. 

How does one deliver microbes from broth and slanted agar?

For broth - Same as removing, simply dip the end of the loop into the broth

For slanted agar - Flat surface up, gently streak in a back and forth zig zag until the entire slanted surface is covered.  

List the microorganisms used and the medium they were transferred to 

Staphylococcus epidermidis transfer to broth 

Escherichia coli transfer to broth 

Neisseria sicca transfer to agar slant 

Bacillus subtilis transfer to agar slant

List Koch’s Postulates. What are they?

A set of rules that dictate the causation of a disease.

The organism must be present in every case of the disease. 

•The organism must be isolated in pure culture in the laboratory.

• The organism must be put into a susceptible host and cause the same disease. 

• The organism must be re-isolated in pure culture and shown to be identical to the original organism.

Define Aseptic transfer

The term used to describe the process of transferring microbes without contamination 

List the various culture types:

Stock culture - the term for a pure culture maintained and kept alive for the purpose of research 

Pure/axenic culture - culture where only one organism is growing 

Mixed culture - culture where multiple organisms is growing 

Broth culture - Culture within a liquified media 

Define Agar slant

Agar slant - the term for agar being solidified in a slant  

What is TSA and TSB?

Trypticase Soy Agar (TSA) - a culture media used to isolate and cultivate microorganisms

Trypticase Soy broth (TSB) - the same thing but in broth form 

List some of the tools we use in microbiology

1. Bunsen Burner

2. Inoculating loop

3. Tube rack