Aseptic Technique.

Not to forget, the aim of the experiment is to make a culture of bacillus subtillus using aseptic technique.

Materials and method:

 The purpose of streaking plates is to distribute inoculums in such a delicate way that it will separate the bacterial cells from each other.  

1. Firstly I held the loop with a pencil grip and sterilized it in the Bunsen flame.
2. I allowed it to cool
3. Still holding the loop in my right hand, I picked up the sample of agar jelly and flamed the neck of the bottle. I then removed the cap.
4. With the cooled loop, I removed a small amount of agar jelly.
5. I then flamed the neck and recapped the bottle.
6. I picked up the petri dish and spread the agar jelly that was on the loop to the base of the petri dish.
7. Just then I put the lid back on the petri dish immediately.
8. Finally I flamed the loop and allowed it to cool naturally.

Safety Points

Using aseptic technique if safe can prevent contamination such as bacteria, yeast, fungi and spores. Not to mention the environment such as people walking by, windows open and some lab equipment can introduce contaminated air. Extending the safety of the human being, washing hands and tying hair back would be necessary and taking when sick would make the experiment inaccurate. Cleaning all equipment that could be contaminated should be cleaned due to the fact that they can be infected with any sort of chemical bacteria.  

Results:

        Dish 1        Dish 2

Evaluation:

After streaking the agar jelly and totally finishing my experiment, I was happy with the outcome of my result. This is because one plate had not been contaminated and the other did which was positive as I did have a result. I found streaking the plate difficult because there were too many things to do at once such as holding the agar jelly with the lid off in one hand and flaming the loop in the other. By overcoming this problem, I worked with a partner, which didn’t come in handy much as my partner had coughed in to one of the petri dishes. This is what had let bacteria in and contaminated the whole petri dish. If more time were available, I would consider working under more sterile conditions and also take more consideration with each step such as opening the petri dish to a minimum and spending little time on spreading the agar jelly.

Industrial aspects:

Every Scientist that uses micro organisms has to use aseptic technique for their own safety. This will ensure that their culture of micro organism will be pure and therefore it will be free from other micro organism and also ensures that it does not go in to the air which will make people ill. Mentioning brewers, they use the yeast left over at the end of brewing to start their next brew. However, because of changes occurring to the yeast, they have to replace it with a pure yeast culture, about every ten brews. They will keep a pure culture of yeast in the refrigerator on an agar slope - you will culture it on a malt agar plate. Scientist’s main indulgent of aseptic technique is to investigate bacterial samples when while researching bacterial diseases.