Science Buddies: "Ask an Expert"

I have completed an experiment of testing how much glucose is broken down from sucrose molecules in fruits and sugar substitutes in the body by using an invertase enzyme and all my results are mixed… Should there be more of less glucose produced from the sucrose in the body once digested?
URGENT!!! THANK YOU

The amount of glucose produced should be directly proportional to how much sucrose is present. Sugar substitutes have no sucrose so should have zero glucose when you digest them with invertase.

What juices did you test? You could have used solutions of known concentrations of sucrose in water as standards to test the activity of the invertase enzyme. Enzymes have a certain capacity to digest things and once they reach their maximum rate they can't work any faster.

Did you plot a standard curve for a specific amount of invertase with solutions of increasing sucrose concentration? This is very important as it shows that the enzyme is working properly and allows you to calculate how much sucrose was in the juice or whatever you tested.

Hope this helps with understanding your results. Repost with more details about your experiment and we may be able to help you better.

Good luck

Invertase catalyzes the hydrolysis of sucrose to fructose and glucose. Yeast produces two different types of invertase: extracellular and intracellular. The extracellular invertase undergoes extensive glycosylation and modifications before it is sent to the periplasmic space. Moreover, the activity of extracellular invertase can be repressed at high glucose concentrations. In contrast, intracellular invertase remains in the cytoplasm, does not undergo processing, and it not subject to regulation by glucose. In fact, synthesis of intracellular invertase tends to be constant. In sum, the amount of glucose produced may be affected by the concentration of glucose and by the type of invertase tested in your experiment. You can check this article for more information at http://www.jbc.org/content/273/37/24102.full. as well as the site www.yeastgenome.org.