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Name: Ryan
Status: student
Grade:  n/a
Location: Outside U.S.
Country: Australia
Date: Spring 2012

What bacteria will grow on lollies/candy that has been wiped over an agar plate?

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I'd just add, for Ryan's benefit, that agar is the food or growth medium for the bacteria. The lolly or other candy could also serve as a medium upon or throughout which the bacteria might grow. Bacterial growth through products which are eaten is a typical cause of disease in humans, pets, etc. The normal procedure is to prepare agar, then add bacteria to the surface of the agar to observe the growth, if any.

To answer the question he posed, I would offer that if the agar is newly prepared and sterile, it ideally should have no bacterial cultures upon it which might be transferred by wiping the lolly across it. IF THE AGAR HAS BACTERIA UPON IT, MEANING IF IT IS NOT STERILE, YES, INDEED BACTERIA COULD AND WOULD LIKELY BE TRANSFERRED TO THE LOLLY. Obviously, nothing like this should ever be consumed or eaten. A general rule is that nothing existing in a laboratory should EVER be eaten.

Just offered for clarification as Ryan's question seems to infer the thought that the agar is a bacterial source. If sterile, it should not be. If infected by using a loop, indeed it could be.

Thanks for using NEWTON! Ric Rupnik

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