Date of Graduation

8-2013

Document Type

Thesis

Degree Name

Master of Science in Food Science (MS)

Degree Level

Graduate

Department

Food Science

Advisor

Latha Devareddy

Committee Member

Luke Howard

Second Committee Member

Ronald Prior

Third Committee Member

Craig Coon

Keywords

Pure sciences; Biological sciences; Anthocyanins; Aronia melanocarpa; Chlorogenic acid; Chokeberry; Flavonoids; Quercetin

Abstract

Flavonoids, such as anthocyanins, may be responsible for the health benefits of chokeberries, as they are present in large quantities in chokeberries and are potent antioxidant and anti-inflammatory agents. Despite these health properties, previous investigations on the bioavailability of flavonoids illustrate that little of the ingested amount reaches the bloodstream. This study investigated two factors that may help to explain these inconsistencies. First, storage of berry fruits and berry fruit products leads to extensive polymerization of their anthocyanins with procyanidins. Additionally, after consumption flavonoids may undergo metabolism into phenolic acids and subsequent conjugation to an extent that may explain their notable health properties despite their low absorption. Thus, the ultimate goal of this research was to determine the optimal storage conditions for retention of not only bioactive, but also bioavailable components in chokeberry juice that can provide cheaper alternatives to disease prevention. The effect of storage on the absorption and metabolism of flavonoids was investigated by identification and quantification of anthocyanins in the plasma and phenolic acids and their conjugates in the urine of rats after consumption of fresh (FCB) versus aged (ACB) chokeberry juice. Anthocyanins were not observed in the plasma of rats that received FCB nor ACB, reinforcing the limited bioavailability of anthocyanins. However, 3 phenolic acids, benzoylaminoacetic acid (BAA), benzoic acid (BA), and 3,4-dihydroxybenzoic acid (34HBA), were identified and excreted in higher quantities from rats that received chokeberry juice than rats fed de-ionized water (CTRL), indicating consumption of chokeberry juice may lead to the absorption of these compounds. Furthermore, consumption of FCB leads to higher excretion of BAA, a metabolite of chlorogenic acid and quercetin, than consumption of ACB. Further research on the metabolism and health properties of phenolic acids is necessary to understand the role of polyphenol-rich berries in chronic disease prevention.

Share

COinS