Biological and Health-Promoting Potential of Fruits from Three Cold-Hardy Actinidia Species

Fruits are essential components of the human diet, valued for their diverse bioactive compounds with potential health-promoting properties. This study focuses on three cold-hardy <i>Actinidia</i> species, namely <i>A. arguta</i>, <i>A. kolomikta</i>, and <i>A. polygama</i>, examining their polyphenolic content, antioxidant/antiradical activities, scavenging capacity and effects on intestinal cell viability (Caco-2 and HT29-MTX). A comprehensive profile of their phenolic compounds was identified, in descending order of total polyphenol content: <i>A. kolomikta</i> > <i>A. arguta</i> > <i>A. polygama</i>. Across species, 16 phenolic acids, 2 flavanols, 2 flavanones, 11 flavonols, and 3 flavones were quantified, with caffeine as a prominent compound. <i>A. kolomikta</i> achieved the highest antioxidant activity, with 'Vitakola' cultivar showing almost double the antioxidant activity compared to 'Tallinn' and 'Pozdni'. By contrast, <i>A. arguta</i> 'Geneva' and <i>A. polygama</i> 'Pomarancheva' exhibited significantly lower activity in both FRAP and DPPH assays. Notably, <i>A. kolomikta</i> cultivars showed distinct radical-scavenging capacities, particularly for superoxide, wherein 'Tallinn' and 'Pozdni' achieved the highest values. Cell viability tests on Caco-2 and HT29-MTX cells revealed a dose-dependent reduction in viability, notably stronger in Caco-2 cells. Overall, this study underscores the therapeutic potential of <i>Actinidia</i> species.