WomenTu Youyou in Science

Who is Tu Youyou?

Tu Youyou (1930-) is a Chinese pharmaceutical chemist with no formal training in modern medicine practice or research who has risen through the ranks to become chief scientist at the China Academy of Traditional Chinese Medicine. Her field of study is in traditional Chinese and herbal medicines. In ancient medical texts she found a reference to using sweet wormwood to treat intermittent fevers--a symptom of malaria. Youyou and her research team decided to see what they could find, and were able to extract a malaria-inhibiting substance called artemisinin from the wormwood. Feeling confident in their findings, she volunteered to be the first human subject to test the substance. Since her discovery of artemisinin in the 1970s, antimalarial drugs based on the substance have saved millions of lives. This research led to her winning the 2015 Nobel Prize in Physiology/Medicine. It’s surprising what we can learn from the ancients. In her research Youyou isolated and then extracted substances from a plant--that’s what you’ll be doing today as you isolate and extract DNA from a strawberry!

Set up:

Pluck all the greenery from the two strawberries then place them in the zip top bag, letting the air out before sealing. Gently smash the strawberries for about two minutes, completely crushing them. This will start to break open the cells and release the DNA. In one of the cups, you will be making your DNA extraction liquid by mixing together the detergent, the salt, and the water with the coffee stirrer or craft stick. Add 2 teaspoons of the resulting mixture to the bag with the strawberries. This will further break open the cells. Reseal the bag, again making sure to let out all the air, and gently smash for another minute (avoid making too many soap bubbles).

Place the coffee filter inside the other cup. Open the strawberry bag and pour the strawberry/DNA extraction liquid mixture into the filter. You can twist the top of the filter and gently squeeze to release liquid out through the bottom. You don’t want any large chunks to get through though so be sure to not break the filter. Once you’ve squeezed out as much as you can, take the COLD rubbing alcohol and pour down the side of the cup an equal amount to that of the strawberry liquid. DO NOT stir or mix. You have just isolated the strawberry’s DNA from the rest of the contents of the cells!! Wait a few seconds and you will see a stringy white cloudy substance (the DNA!) developing in the top layer of the liquid in your cup. Use a toothpick to pick up and examine the DNA! You’ve just isolated and extracted a substance from a plant just like Tu Youyou did!

What you will need:

1 zip top plastic bag 1 coffee filter 2 cups A small amount of COLD rubbing A teaspoon measuring spoon alcohol (place in the freezer a few A ½ cup measuring cup hours beforehand) 2 strawberries 1 toothpick 2 teaspoons of dishwashing detergent 1 coffee stirrer for mixing ½ cup of water 1 teaspoon of salt