Tstl Penelope L S Pta

Pour visualiser mon diaporama, Appuyez ici

Pour écouter ma présentation orale =} Appuyez ici


Concernant la présentation orale.

Tu parles trop vite: Il faut bien prononcer tous les mots !

La durée est un peu courte (4:01 mins au lieu de 5 mins!),

Attention à la prononciation du morphème –ed : "washed", "the results that we expected",

"The following problematic" =} "the following problem-question"

Quelques erreurs à éviter comme "other experiences =} other experiments ainsi que la dernière phrase de ta présentation.

Les phrases suivantes sont mal dites : "It's important to know that ???? doesn't wash your hands". "They constitute ???? commensal flora…"

Attention à la prononciation de certains mots comme "quantities", "E-coli"

C'est assez bien présenté et ton texte est bien écrit.

Subject of study: the functions of the antibacterial gel

The cutaneous commensal flora:

Many bacteria are normally present on the skin and mucous membranes of healthy subjects. They constitute the resident commensal flora. They actively participate in the maintenance of health. For example, the intestinal flora synthesizes vitamin K, helps in the absorption of food, prevents by its balance the proliferation of potentially dangerous commensal bacteria and hinders colonization by pathogenic bacteria.

Commensal bacteria can be divided into 4 main flores (cutaneous, respiratory, genital and digestive).

The cutaneous flora is variable in quality and quantity.
- The resident flora is made up of Gram + germs that are potentially low pathogenic, in significant quantities in the samples and present in the hair follicle.
-The transient flora is more varied and may include potentially pathogenic germs from the digestive tract:
Enterobacteriaceae, Staphylococcus aureus …
The antibacterial gel:
The hydroalcoholic solutions are skin aseptic solutions. They are used to ensure hand hygiene, particularly during medical care. They act by direct contact and can be used without water. The hydroalcoholic solutions have bactericidal, virucidal and fungicidal properties, without cleansing effect. They must be applied to dry and unsoiled hands. Depending on the different pharmaceutical specialities, these solutions consist of different active ingredients including alcohol and an antibacterial agent.

Microorganisms are etymologically "small organisms", that is living beings so small that they are not observable only with a microscope. This term encompasses a variety of very different species, whether prokaryotes (bacteria) or eukaryotes (yeasts, algae). Some also include viruses, although they are at the limit of life.
We wonder how the sensitivity of certain microorganisms to the antibacterial gel is different?
Our hypotheses
We thought about several hypotheses to apply our experiments and deduce conclusions. Here we will focus on cell viability and washing hands.
Cell viability
if you sow yeast and fungi and put antibacterial gel on them and there is nothing left then the antibacterial gel also has the function of being fungicide.
For this we have done cell viability on yeasts.
Hands washing
if we put our finger on a first agar we should observe 100% of our bacteria, after we put our finger with antibacterial gel on a second agar we should observe 1% of the bacteria observed on the first agar. Following this hypothesis, we set up the hand washing protocol.
Protocol and results
Cell viability : To carry out this protocol we made a test tube and a control tube, in the test tube we put 0.9mL of Candida Albican suspension and 0.1mL of fungicide solution, in the control tube we put 0.9mL of C suspension. Albican with 0.1mL distilled water. Then we incubated the whole thing for 1 hour at 30°C. After the incubation we re-tubed, for the test we put 0.5mL of the test tube that was incubated and 0.5mL of funk blue and in the control tube we put 0.5mL of the control tube incubated with 0.5mL of funk blue. We then counted using the hematimeter.

Test control

control : all living cells
test : 1111 dead cells - 0 living cells
so viability = number of living cells/ total number of cells = 0/1111=0%.
cell viability is 0% so this means that no cells have resisted the antibacterial gel and therefore the antibacterial gel is very effective against yeast. So we can conclude that the antibacterial gel used is fungicidal.

Hands washing : To carry out this protocol we took contact agar and put our hand on it, we made agars where our hands were not washed, another where our hands were washed with soap for 30 seconds and 1 minute and we also made some by washing our hands with antibacterial gel. We used contact agars from different media: like Sabouraud agar which is a yeast isolation medium, we also used PCA agars which are non-selective, for Gram + isolation we used Chapman agar and finally we used Drigalski agars for Gram - isolation.

Soap 30s unwashed
To begin we made control agars where we observe only one colony on the Drigalski River, few colonies on the Chapman River and numerous colonies on the Sabouraud and PCA.
We observe on Drigalski agars that there is never a colony except one on the agar where we put our unwashed hand we can say that there is no gram - on the skin commensal flora and that the gel and soap destroy all the gram - present on our hands. The agars where we washed our hands for 30 seconds with antibacterial gel contain no colonies which means that the gel is effective when we wash our hands for 30 seconds while the agars where we washed our hands with antibacterial gel for 1 minute contain about ten colonies on all the agars except on the Drigalski where there are none which means that it is more effective to wash our hands by rubbing the gel on them for 30 seconds, rubbing your hands together longer could bring bacteria back on your hands. On the agars where we washed our hands with soap for 30 seconds we observe colonies in average quantity which are always more numerous than when we wash our hands with gel, the gel is thus more effective.
On the agars where we washed our hands for 1 minute with soap there is no more colony on the Sabouraud and on Chapman we observe a small quantity of colony and on the PCA we observe a very large quantity of colony which means that washing one's hands for 30 seconds with soap is less efficient than washing them for 1 minute.
To conclude the choice of his two experiences can answer our problem. As far as hand washing is concerned, he confirms that bacteria (E.Coli and S.Aureus) are sensitive to the antibacterial gel. It is then according to their peptidoglycan layer (Gram + and Gram -) that it is thick or not it does not resist this solution and is destroyed. The cell viability of the yeast used (C.Albican) is 0%, it is also sensitive to frost, the fungus is not resistant enough. This will confirm the properties of the antibacterial gel, which are bactericidal and fungicidal. There was then a strong chance that our bacteria and yeast would not resist.

Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License