Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

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rishi10802
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Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by rishi10802 »

Hi,

In the above project, did you use cream or liquid form of the antifungals that you tested in your experiment?
As far as testing tea tree oil,citronella oil could they be tested in oil form using your set up or do they have to be formulated in cream form?
If in oil form how much of it should I use to test?
If they have to be formulated in cream form could you suggest how I should go about doing it?
Zinc was another one suggested as a natural antifungal - which one do you suggest cream form or powder form in which case it has to be formulated in cream or ointment form.
SciB
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Re: Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by SciB »

Hi,

In your experiment, the yeast (which IS a kind of fungus, by the way; but it can't harm humans) is suspended in sugar water, so you want to make sure that the antifungal agent is dispersed as completely as possible in the liquid before you add the yeast. Creams and ointments for applying to the skin do not dissolve in water very well. You could try warming the water to about 50 C [130 F], adding the antifungal compound and mixing until the suspension is as complete as possible. Just be sure to cool the liquid to about 38 C [100 F] before you add the yeast. If the liquid is too hot it can kill the yeast.

For the Zn compound, I would try the powder first. if it all settles out and does not stay suspended then try the cream form.

Be sure to run each test at least three times, including the control with just sugar water. You can calculate the average of the three readings and do some statistical tests on it. These will add a lot of strength to your conclusions. Also, make sure you have no leaks in the gas line. This is really important because if the gas is leaking then all your readings will be wrong.

Good luck!

Sybee
rishi10802
Posts: 5
Joined: Fri Nov 20, 2015 5:06 pm
Occupation: Student

Re: Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by rishi10802 »

Thank you so much for your help!
rishi10802
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Joined: Fri Nov 20, 2015 5:06 pm
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Re: Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by rishi10802 »

Hi,

What would be better - should I just test the natural antifungals (tea tree oil etc) or test both the natural and the OTC antifungals ( terbinafine etc) and compare them? Which would be a better project without making it too complicated?
SciB
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Re: Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by SciB »

Hi,

I think comparing herbal or 'natural' antifungals with synthetic ones is a great idea. Maybe two of each type of antifungal would be enough since you need to do three tubes for each one in order to get statistically meaningful data.

Would it be possible for you to set up three graduated cylinders to collect CO2 at the same time? Doing the experiment this way would make it much easier than having to run each tube one at a time. The main thing you have to be careful with is to have the tubing sealed completely so that there are no gas leaks. Also, be sure to make your yeast suspensions EXACTLY the same each time. If the amount of yeast or sugar is different then you won't get the same amount of CO2 produced.

Scientifically, the best way to do this experiment would be to have 6 tubes with gas collectors--three for controls without antifungal, and three for the antifungal. This way you would use the same yeast-sugar suspension for the controls and the experimentals so there would be no chance of error. I don't expect you to run 6 tubes at one time, however. I just wanted you to know how a researcher would set up an experiment like this to minimize errors.

The other thing to think about is how you define natural and synthetic antifungals. A plant extract like neem oil would definitely be 'natural' and a chemical like ketoconazole or clotrimazole would be synthetic. Just be sure to read the label of an antifungal to make sure it does not contain a combination of natural and synthetic antifungals.

Let us know if you have more questions.

Sybee
rishi10802
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Joined: Fri Nov 20, 2015 5:06 pm
Occupation: Student

Re: Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by rishi10802 »

Thank you.

Essential oils do not dissolve in water totally. When the essential oil is added to the yeast/salt mixture it will not mix properly. Do you have any suggestions? I researched but to no avail.

Also, you had mentioned in your previous reply to use 6 tubes with gas collectors--three for controls without antifungal, and three for the antifungal. DOES THAT MEAN THAT I HAVE TO HAVE 3 CONTROLS FOR EACH TIME I TEST THE INDIVIDUAL ANTIFUNGALS?

ALSO COULD I SET UP THE TESTS IN ONE BUCKET OR WOULD I NEED TO DO TEST IN DIFFERENT BUCKETS?
rishi10802
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Joined: Fri Nov 20, 2015 5:06 pm
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Re: Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by rishi10802 »

What I meant to ask is that are there any sulubilisers (eg ethanol?)that I can add to the mixture without affecting the results?
SciB
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Re: Yeast Busters: Stopping Fungus in its Tracks with Antifungal Medicines

Post by SciB »

Hi,

I know what you mean about using essential oils in water--they won't dissolve. But you can emulsify them by using a soap. Now, I don't know which soap to use or how much. Dr Bronner's pure Castile soap is supposed to be one of the gentlest, so you could try that. Most health stores carry it. I would not use a detergent because I think that might inhibit yeast growth.

The best thing to do is get some soap and try it on your yeast and see if it affects gas production. You will also have to experiment a little to decide how much soap you need to solublize a certain amount of oil.

In regards to your question about the controls, I would strongly suggest that you do a set of controls each time you test an inhibitor. If you had a set-up where you could test everything at once you would only have to do one set of controls, but I think 6 tubes is probably the most you can do at one time. You can use one pail for collecting gas from the control and a different one for the inhibitor. They do not have to be in the same pail. Yeast likes to be warm, so try to do the experiments in the same place each time and hopefully you have a spot where it is at least 27C [80F]. Be sure to record the temperature in your lab book each time. That's another reason to do controls each time because the temperature may vary. If you were doing this experiment in a lab you would use an incubator that controls the temperature to within a few tenths of a degree.

The other important factor is the amount of yeast in each tube. In order to make the cultures as identical as possible, you should prepare one suspension of yeast--enough for all 6 tubes--and pipet an identical volume into each tube. Be sure to shake the container with the yeast gently each time before you pipet to make sure that the yeast is uniformly suspended.

Let us know if you have more questions.

Sybee
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