Definitely Need Antioxidants Alix Kong Collingwood School Floor Location: J84H

Our body acts as a barrier and a machine to our cells, organs and bones. Every second of our life is put into body repairs and to make it healthier for longer periods of time. DNA (deoxyribonucleic acid) is a nucleic acid that contains genetic info scientists can use for many purposes (ie: cloning, repair defects, solve crimes, etc.). Antioxidants are a form of nutrients that are responsible for protecting the body’s cells and decrease the possibility of infectious diseases. Together DNA and antioxidants work together as an important team.

When we breathe oxygen, we produce free radicals which are organic molecules that destroy cells by stealing an electron from healthy cells and making them unstable. This can cause illnesses like diabetes and heart disease. Antioxidants repair cells by donating electrons back and making them strong again.

My hypothesis stated that fruits and vegetables that are high in antioxidants will have more visible DNA because they produce more antioxidant molecules. By conducting this experiment I will be able to tell what fruit or vegetable has more antioxidants by extracting its visible DNA. The more antioxidants there are, the more beneficial that fruit/vegetable is to the body.

My procedure was very complex. I decided to test 2 fruits and 2 vegetables - both with one high and one low in antioxidants. The first step was to prepare materials before starting my experiment so I put some isopropyl into the freezer for 2 hours and a pot of tap water was heated to 60 degrees C. Then an extracting solution made of salt, water and dish detergent was produced. The next step was breaking down of the fruit or vegetable cell membrane and making it into pulp. I then added the extracting mixture to the pulp and put it in a hot bain-marie for 15 min, then in a cold bain-marie for 5 min. The process of filtration followed by pouring the extraction solution through a sieve into a beaker. Pineapple juice (proteolytic enzyme) was then added to purify the solution. The last step was to slowly pour the isopropyl into the test tube, which separated the DNA from the pulp. This procedure was repeated 3 times.

By extracting the visible DNA, I could determine which fruit/vegetable had the most antioxidant molecules. In conclusion, my hypothesis was correct and my results also indicated that the coronation grapes and spinach (darker in colour) contained more antioxidants and more visible DNA than the white onion and kiwi (light in colour). In conducting this experiment, I was able to find an inexpensive way to identifying fruits and vegetables high and low in antioxidants. In the future, doctors can easily determine what foods have more antioxidants and can lower the risk of infectious diseases. My experiment this year was a success. In the future, I would like to test a larger sample of colorful fruits and vegetables. We Definitely Need Antioxidants!