Once again I was demonstrating for lab practicals on Monday and Tuesday this week, so I had to plan my week carefully in order to fit in finishing off Gram staining, Indole and Oxidase testing. I also needed to try and start working with the Spiral Plater DS+ towards the end of the week.
Monday 25th November
As I was demonstrating for a lab practical all day I didn’t start my own lab work until late. I only needed to make some more MacConkey agar plates, so I made up the agar and autoclaved it. Once cool enough I poured my plates aseptically, leaving them to set before inverting them.
Tuesday 26th November
Once I had finished my lab demonstrating for the day I continued my own lab work by inoculating MacConkey agar plates. I started by removing the last of my samples from the freezer, allowing them to warm to room temperature before vortexing them. Then, I aseptically spread plated the samples before incubating them overnight at 30ºC.
Wednesday 27th November
I was able to start my day fairly early, and began by removing my spread plates from the incubator. I then observed and photographed each plate carefully. The lab I work in has a new cabinet, which I have been wanting to use but haven’t had the opportunity yet. Currently the labs are being reviewed for gas leaks and there is no gas in the small lab I usually work in. I have been using the gas in the main teaching lab, however as the cabinet was free I decided to use it to complete my tryptone broth inoculation, heat fix slides and oxidase testing.
After cleaning all my materials down with ethanol, as well as my gloves, I began work in the cabinet. As the cabinet has regulated air flow all procedures are much easier and quicker to complete, so I was excited to try it out! I inoculated tryptone broth with my chosen samples, for indole testing. These were then incubated overnight at 30ºC.
I continued by heat fixing slides for Gram staining of those samples which hadn’t been stained yet. Once heat fixed I Gram stained them before viewing under light microscopy, noting down the result and cell morphology for each sample.
Gram stained sample, demonstrating Gram negative rod shaped bacteria
Finally I completed oxidase testing on those samples which hadn’t been tested yet. I observed any colour changes and noted these down for each sample.
Thursday 28th November
I began my day by removing my inoculated tryptone broths for the incubator. I then added 5 drops of Kovac’s reagent, observing each sample for colour change and noting down the results.
Once finished I decided to begin setting up and cleaning the spiral plater. I started by following the set up instructions supplied in the manual, connecting the main unit to the vacuum pump and arranging the accessories correctly.
I then filled the side tray with ethanol and distilled water to allow the spiral plater to conduct a cleaning run. After reviewing the manual I then ran the spiral plater through several cleaning runs (To watch video of procedure click here).
After this I decided to trial run the spiral plater on an empty plate using distilled water. This allowed me to have a trial run through the procedure and observe the spiral plater working. I then used a MacConkey agar plate and crystal violet dye to test the position and accuracy of the spiral plating. This worked very well, and therefore I didn’t need to re configure the stylus (To watch video of procedure click here).
At this point I was happy with the set up and basic running procedure. As I don’t currently have any samples to test run through the spiral plater I decided to finish lab work for the week and collect a sample to trial run through the spiral plater procedure next week.
Now I have completed all testing I wanted to complete on the bacterial collection, all that is left to do is input this new data into my bacterial database spreadsheet and conduct a final identification. I’m really happy with all the procedures I have conducted so far in the identification process and I’m looking forward to moving onto trial running new samples. Next week I plan to collect a trial sample from Lincoln in order to work through the procedures I will need to prepare and growth freshly collected samples.
A Year in the Life…