Essay on Tutorial workbook

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Session 8: Flavonoids
Quercetin is a flavonoid. Its known for its powerful antioxidant properties due to its ability to protect against oxidative stress. This is generally done by inhibiting oxidation and scavenging free radicals. Its antioxidant action provides neuroprotective, cardioprotective, and chemopreventive affects on the body (Williams, Spencer and Rice-Evans, 2004), providing protection against disorders such as Alzheimer’s (Heo & Lee, 2004), stroke (Keli et al. 1996) and cancer (Knekt et al. 1997). In cases of Alzheimer’s studies have shown protection against neurological degeneration by preventing lipid preoxidation (Wagner et al. 2006) (Kumar et al. 2003). Graf (et al. 2005) proved cardio vascular disease can be reduced by 21% through Quercetin ability to inhibit LDL oxidation. And an animal study supported the theory that quercetin has an anticarcinogen affect through a study on mice showing tumor multiplicity and development was suppressed by inhibiting azoxymethanol (AOM)-induced colonic neoplasia (Deschner et al. 1990).

Vitamin C is also an antioxidant. Quercetin and Vitamin C have been linked in treating similar disorders and as a result often compared in healing ability. Ultimately studies show that Quercetin is more effective affect in treating oxidation (Heo & Lee, 2004) (Noroozi, Angerson, Lean, 1998) however if used together often have a synergistic effect (Heo & Lee, 2004) (Prabu, 1997). Dr. Albert Szent-Gyorgyi won Nobel Prize for research relating to the combined effects of Vitamin C and Quercetin who found positive results on patients with blood vessel problems only when the two antioxidants were combined, as opposed to Vitamin C alone. Prabu et al. demonstrated that Vitamin C & E with Quercetin had a protective affect against cadmium toxicity in rats. Chen et al (2005) concluded through in vitro studies that flavonoids (via Almond skins) act synergistically with Vitamin C and E to protect against LDL oxidation.
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