Historically, Camellia sinensis (tea) is a plant that has been known to contain antioxidants. Antioxidants such as catechins have been demonstrated to be chemopreventive agents. This review aims to summarize recent findings on the anticancer properties of tea, and its constituents. Since tea is taken orally, and one of the easiest entrances into the human body for microbes is through the oral cavity, this review will focus mainly on oral cancer.
Through animal and epidemiological studies, the main active ingredient responsible for the anticancer properties of tea has been determined to be the catechin (-)-epigallocatechin gallate (EGCG). Tea constituents were analyzed through the use of HPLC and confirmed by comparison to authentic standards and mass spectrometry.
The results obtained from some studies conflicted with earlier notions that tea catechins act as antioxidants, inhibiting cancer cells. They discovered the catechins to have a pro-oxidant effect, generating reactive oxygen species, such as H2O2. Methods of cancer inhibition were also explored, including cell cycle arrest at certain checkpoints and induction of apoptosis, the active process of cell death.
Results from a current study were also examined. Anti-viral and anti-bacterial effects of green and white teas were determined using the plaque method and the Kirby-Bauer, disk-diffusion technique. Results indicated the power of whole tea and tea constituents alongside toothpaste and gum. More than 99% inactivation of viruses was obtained in ten minutes using Tom’s of Maine toothpaste with white tea, whereas infusion of tea into chewing gum yielded over 90% inactivation. Furthermore, distinct zones of inhibition were present for toothpastes and gum treated with tea than for the oral agents by themselves. The future of the research was also briefly discussed.
Although many studies have shown beneficial properties of Camellia sinensis, much more epidemiological research remains to be conducted in order to observe the effects on human cancer cells.
Krieger, Tatyana, "Camellia sinensis constituents: A Review of Oral Cancer Prevention" (2007). Honors College Theses. 58.