Comparative Analysis of Antioxidant and Anti-Amyloidogenic Properties of Various Polyphenol Rich Phytoceutical Extracts

Though the pathogenesis of Alzheimer’s Disease (AD) is not completely elucidated, it is generally accepted that the aggregation of toxic amyloid-β (Aβ) protein fibrils plays a major role in the disease’s onset and progression. Various phytoceutical compounds have been shown to attenuate Aβ toxicity and disrupt its aggregation, including various types of polyphenolic compounds. These polyphenolic compounds have also been found to demonstrate potent antioxidant activity, which may contribute to their anti-amyloidogenic properties. This study compares three plants, traditionally used for numerous medicinal purposes in Asian countries, including: Curcuma longa (Turmeric), Camellia sinensis (Green Tea), and Scoparia dulcis (Sweet Broomweed). Antioxidant effects of the crude, polyphenol rich phytoceutical extracts from these plants were analyzed using a 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The ability of these extracts to prevent Aβ fibril formation was then carried out in order to establish a relationship between antioxidant activity and Aβ aggregation. A positive correlation between antioxidant efficacy and prevention of Aβ aggregation was demonstrated, indicating that antioxidant activity may play some role in preventing Aβ aggregation.