Richard Johnson and Christine Hermann. Radford University, Radford, VA
Lycopene is a fat soluble carotenoid. Being an strong-antioxidant it helps to prevent many degenerative diseases. Lycopene can be found in red and yellow tomatoes but not in green tomatoes. The double bonds of this red pigmented molecule can be broken using a solution of bromine water. When bromine water is added to tomato juice, bromine is added across the double bonds of lycopene. As this occurs a spectrum of colors emerge depending on the concentration of lycopene. This experiment was done as an Honors contract for Organic Chemistry 301, with an attempt to improve on an already published procedure. The variables of the experiment was changed to include not only red tomatoes, but yellow and green tomatoes as well as store-bought tomato juice. The experiment illustrated the halogenation of alkenes in a very colorful experiment.