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Spit Happens: The Breakdown of Starch Through Salivary Amylase

Spit Happens: The Breakdown of Starch Through Salivary Amylase
Spit Happens: The Breakdown of Starch Through Salivary Amylase

Category: Research Poster

Author(s): Megh Enright, Isabella Gunn

Presenter(s): Megh Enright

Mentors(s): Carlos Olivo-Delgado

Salivary amylase is an enzyme that investigators can use to confirm the presence of saliva through hydrolysis of starch into smaller sugar molecules. The enzymatic activity of amylase can be observed by using a starch-iodine reaction. Starch and iodine react together to create a dark blue color, but in the presence of amylase that color turns somewhere from yellow to clear. Using UV-Vis to better confirm these color changes, we were able to determine amylase levels in several different suspects. In this experiment, saliva and a 0.5% starch solution were combined and incubated for 5 minutes, and then iodine was added to see if a color change was present. This test is often used to determine if saliva was present at a crime scene. DNA testing multiple people is an expensive process and analyzing amylase levels is the easier and less expensive alternative. Testing suspects' amylase levels makes it more possible to reduce the number of suspects undergoing DNA testing and improves the forensic field.