Black chokeberry juice consumption seems to be effective also in urinary tract infections (UTI) treated by antibiotics, as was shown in the study of Handeland et al. 111 During a period of six months, the juice (156 mL per day), which was characterized by a high content of total phenolics including B-type procyanidins, anthocyanins and chlorogenic acids, was applied to residents in nursing homes.
The lipophilic and hydrophilic antioxidant capacities, measured by oxygen radical absorbance capacity in berries of black chokeberry, Ribes nigrum (black currant), Ribes rubrum (red currant), Ribes grossularia (gooseberries) and Sambucus nigra (elderberry), were provided by Wu 65 However, the lipophilic antioxidant capacity was quite low; the hydrophilic capacities for black currant, chokeberry and elderberry are among the highest of fresh berry fruits. The chokeberry had significantly higher antioxidant activity related to the higher content of anthocyanins and phenolics than the other three berries. Despite the predominate position of anthocyanins among polyphenols, their absorption is very poor and low for the small intestine (in the case of cyanidin 3-glucoside 22.4%, cyanidin 3-galactoside 13.6%) and stomach, as well 80 , 81 , 82 After absorption, anthocyanins are transported with the circular system to various organs and tissues, including the liver, heart, prostate, testes, brain and body fat, but they are mostly distributed to the urinary bladder and kidney of rats 83 , 84 The low rate of absorption of anthocyanins and another polyphenolic compounds in black chokeberry fruit can be explained by their transformation, modification by methylation or conjugation with glucuronic acid 81 , 85 , 86 For example, cyanidin 3-glucoside is methylated and glucuronidated, cyanidin 3-galactoside oxidized, and finally, all derivates (conjugates) are eliminated by the urinary system 82 , 86 , 87 Another way is an extraction with the bile 81 or with the feces 85 On the other hand, anthocyanin conjugation is probably responsible for their metabolic activation and health benefits in relation to chronic diseases 17 , 87.