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 Actinidia species, namely A. arguta, A. kolomikta, and A. polygama, 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: A. kolomikta > A. arguta > A. polygama. Across species, 16 phenolic acids, 2 flavanols, 2 flavanones, 11 flavonols, and 3 flavones were quantified, with caffeine as a prominent compound. A. kolomikta achieved the highest antioxidant activity, with 'Vitakola' cultivar showing almost double the antioxidant activity compared to 'Tallinn' and 'Pozdni'. By contrast, A. arguta 'Geneva' and A. polygama 'Pomarancheva' exhibited significantly lower activity in both FRAP and DPPH assays. Notably, A. kolomikta 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 Actinidia species.