A strong association has been found between mutated p53 tumor suppressor genes and cancers in humans. Cancers arise from a culmination of genetic and environmental factors, including exposure to ultraviolet (UV) light from the sun. Prolonged exposure to UV has proven negative effects on cell homeostasis. Much of the damage caused by UV light exposure is through generation of free radicals. Zeaxanthin and melatonin are known antioxidant/free radical scavengers which protect cells by neutralizing damage causing free radical molecules. This study was conducted to determine the effectiveness of zeaxanthin and melatonin in preventing the negative effects of UV light on cell viability and cell cycle control. The analyzed parameters of cell health were cell survival and cell cycle staging using flow cytometry. UV light treatments had a negative effect on the cell viability and showed increased numbers of cells in cell cycle arrest. Both treatments with zeaxanthin resulted in increased cell replication and increased cell cycle arrest. However, the control group were the only cells that survived the treatment and all zeaxanthin treated cells died. These preliminary results indicate that zeaxanthin did not provide protection from the UV light damage since there was an increase in cell death cell cycle arrest. The results of the melatonin experiments showed that at the concentrations used no effect was evident. The effects of zeaxanthin and melatonin on preventing free radical damage needs further investigation, as current literature indicates that treatments using free radical scavenging products reduce potential tumorigenic damage from UV light.

Semester/Year of Award

Fall 11-10-2022


Professor Oliver Oakley, Department of Biological Science

Mentor Department Affiliation

Biological Sciences

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Open Access Thesis

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Honors Scholars

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