Transformations of Phenolic Compounds in an in vitro Model Simulating the Human Alimentary Tract
Tomasz Tarko*, Aleksandra Duda-Chodak, Pawel Sroka, Paweł Satora and Jolanta Michalik
Department of Fermentation Technology and Technical Microbiology, Food Technology Institute, University of Agriculture in Krakow, ul. Balicka 122, PL-30-149 Krakow, Poland
Article history:
Received November 26, 2008
Accepted June 16, 2009
Key words:
phenolic compounds, fruits, in vitro digestion, dialysate membranes, antioxidant activity
Summary:
The aim of this work is to establish the antioxidant properties of polyphenolic compounds of selected fruits before and after their transformations during digestion. The experiment was conducted in in vitro conditions on a set of dialysis membranes which simulated the human digestive tract. Apples of the Šampion, Malinowka and Golden Delicious cultivars, black chokeberry, banana, Wegierka zwykla blue plum, melon and Lukasowka pear were chosen for examination. It was found that compounds obtained after simulated digestion of chokeberries, pears and bananas showed lower antioxidant potential than fresh fruits, while the opposite results were obtained for apples and plums. All dialysates obtained after digestion were characterized by lower content of total polyphenols in comparison with raw material (fresh fruits). It was found that the polyphenols were hydrolyzed, especially glycosides of quercetin and cyanidin. Phenolic acids and cyanidin were characterized by low availability for absorption, whereas catechin and quercetin had a very high level of accessibility in the model small intestine.
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