In the two blood agar plates

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Method

In the two blood agar plates, one needs to draw a line down or better yet have two plates. The plates needed to be well labeled including product as well as procedure that one will use in testing. In this experiment a hand sanitizer containing 62% alcohol and ethanol that is 70% from the lab bench

One half was labelled “pre-wash “and “post-wash” for the other half in order to differentiate between results before and after the experiment

On the half labelled “pre-wash” each group member rubbed their hands (index finger, middle finger and ring finger) back and forth on that agar several times.

Each group member proceeded to wash their hand either the hand sanitizer by rubbing both palms together and going in circular motion and using a nail pick or a hand brush to clean under the nails. It was important to also clean between the fingers.

Hands were rinsed thoroughly for 30 seconds until all the sanitizer is gone

Hands were then left to air dry for two minutes.

Swabs were taken of the clean hands and the swab was placed on a petri dish

The experiment on hand washing was repeated but now using the open bench ethanol with 70% alcohol

Hands were rinsed thoroughly for 30 seconds and left to air dry for two minutes

After washing hands it was important for everyone to avoid touching any surface

Once hands were dry, swabs were taken of the clean hands and placed on the agar labelled post-wash, swab were be taken four times

The swabs were placed on the petri dish and the petri dish covered with a lid before being put inside an incubator

The plates were then incubated at 37 degrees Celsius

The plates were left for 24 hours prior to observation for the colonies to full grow After the plates were incubated, the microbes were observed by counting the number of colonies and record down the results

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Findings

In obtaining the results the number of colonies were counted through visual infection then the aerobic plate count was calculated from the figures that were obtained

From the result the antiseptic showed reduction of microbes from the post wash to the pre wash in four out of six group members. In one these results was the same

In the post wash result only one student had 0% of microbes while in some students several colonies had grown even after the hand washing experiment begging the question what would have resulted in such a huge noticeable difference when same washing detergent were used.

The results from the ethanol bench proved more effective with the greatest difference on the microbe’s reduction as the number of yellow colonies were less compared to the number of colonies in the hand sanitizer

There was difference in the amount of colonies between different students prior to the experiment some exhibited many yellow colonies while others exhibited few number of colonies as everyone had touched different things throughout the day

At different treatment point, the microbes on the hands increased and later declined in the post wash while using the hand sanitizer

As an individual bacterium is small to see with our eyes each small spot we observed a group of millions of bacteria clumped together which we referred to as colonies most appeared yellow before the experiment and after the experiment most appeared white and translucent although there were a few yellow colonies that were still present.

The colonies also presented themselves in different shapes and sized and there was a smell that could be felt from the petri dish

In the open bench result it continually declined then at the end it increased.

When results between the post wash and the pre wash were compared there was a notable difference in the decline of germs between the two results

On petri dish A which contained swab from hand sanitizer: Before: there white and yellow opaque colonies that were small a dark translucent colonies

After: Significant reduction of the colonies but were white

On petri dish which contained the open bench ethanol:

Before: Yellow and white opaque colonies. Multiple dark translucent

After: there was a significant reduction of the colonies most were white and translucent.

On the pre wash there was a creamy colored colony while in the pre was there was one colony that was white colored and translucent and was smooth

There was also no growth reported when the incubation was at thirty seven degree Celsius

The hands also felt dry after washing with the open bench alcohol as well as cool a notable difference when the hand sanitizer was used

The findings observed and data found after calculation of Aerobic Plate count is shown below.

Table SEQ Table * ARABIC 1: Results from the Hand sanitizer

Pre Wash Post Wash

0.002 0.002

0.051 0.000

0.041 0.003

0.255 0.002

0.071 0.001

0.082 0.001

Table SEQ Table * ARABIC 2: Results from the Open bench ethanol

Pre Wash Post Wash

0.979 0.012

0.168 0.003

1.255 0.003

0.897 0.002

0.236 0.004

0.877 0.014

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