MUIH Microbial Analysis Experiment Internship Part III


At last, we have reached the end of this series on the “internship” that is no longer an internship. If you didn’t read the series, you should start at Part I.  The point of this blog series is to illustrate some of the work that I have done and things that I have learned. Since this is a real, ongoing, study involving accredited universities (University of Maryland and Maryland University of Integrative Health), I am not disclosing all materials and methods, analysis, or results.

This last portion of the experiment I have been participated in involved testing botanical extracts against various bacteria, yeast, and mold.  Specifically, I got to test hydro-alcoholic extracts of Echinacea purpurea (commonly known as Purple Coneflower or Echinacea), of varying strengths to see if it inhibited growth of the bacterias, yeast, and mold.  To do this, I created dilutions using 3 different Echinacea tinctures to inoculate, incubate, and interpret results from 3M Petrifilms.

I learned aseptic lab techniques while carrying out the study discussed in Part II of this series. This time around, it was even more important because I was handling petrifilm loaded with yeast and mold spores, and one with E.Coli (yuck!).   Having the experience gained from the first round made it much easier to confidently carry out the steps while limiting exposure.  Some of the additional daily tasks involved taking ambient temperatures, monitoring samples, counting colonies, and reporting results.

I won’t go into all the nerdy details since more will be written (and it’s really the school’s place to properly publish the study and get credit for it).  For now here are some pics of what I’ve been learning and doing.



MUIH Microbial Analysis Experiment Internship Part II

The second part of this post covers the first phase of the actual experiment.  If you missed the first part of this post, you can find it here.  Technically, this is no longer an internship because I didn’t do it for college or work credit.  After all the research and planning for the experiment, I wanted to be part of it.  I was excited about the prospect of participating in a study between two universities, with the possibility of the findings being published.

We were testing the theory that a bunsen burner could create a sterile field. The reason this would be cool is because many product makers are small businesses that cannot afford to rent lab space for product creation.  The execution of the experiment required learning and using aseptic lab techniques (limiting variables), meticulously documenting each step and then counting colonies.


The bunsen burner was turned on for five minutes to create the sterile field.  Measurements on the table indicate the distance of each TSA plate (a.k.a. a petri dish to most) to the burner.  After 5 minutes the lids were removed to expose them to the microbes in the air.
After the predetermined amount of time the lids were replaced and the dishes were wrapped in lab film to keep them secure.
Close up of the dishes before the incubation period.
Here is a couple of days in.


This is after 7 days of incubation. Look at all of those organisms!

The study has not been published yet so I will not discuss the results.  Needless to say, my personal results were… gross.  It was really awesome learning about aseptic lab techniques and getting to participate in this study.

Part III of this post will be the final part and will cover the second, and last, experiment conducted as part of this study.