Probl Hig Epidemiol 2018, 99(3): 238-244pl

Actinidia chinensis as a source of health-promoting antioxidants

Joanna Zielonka-Brzezicka ^1/, Anna Nowak ^1/, Adam Klimowicz ^1/, Daria Wira ^2/, Karolina Grzesiak ^2/, Ewelina Rędzikowska ^2/, Daria Wysocka ^2/, Laura Synowiec ^2/, Barbara Ptak ^2/, Joanna Bilska ^2/

1/ Katedra i Zakład Chemii Kosmetycznej i Farmaceutycznej, Pomorski Uniwersytet Medyczny w Szczecinie
2/ Studenckie Koło Naukowe przy Katedrze i Zakładzie Chemii Kosmetycznej i Farmaceutycznej, Pomorski Uniwersytet Medyczny w Szczecinie

Summary
Introduction. Proper nutrition is one of the preconditions for maintaining good health. Even small dietary modifications, including, for example, the introduction of more vegetables and fruits, may reduce the risk of some chronic non-infectious diseases. Fruits and vegetables are a valuable source of active compounds with broad ranging biological activity, including antioxidant potential. One of the better known and easily available fruits, containing vitamins, carotenoids and polyphenols - all valuable antioxidant dietary components - is kiwi fruit.
Aim. The aim of the study was to compare the antioxidant activity of alcoholic extracts from various parts of Actinidia chinensis, using three methods to evaluate their properties.
Materials & methods. The research material consisted of Actinidia chinensis fruits including their isolated pulp, peel and seeds, obtained using ultrasound-assisted extraction in 70% and 96% (v/v) ethanol and in concentrated methanol. DPPH, FRAP and Folin-Ciocalteu methods were applied to evaluate the antioxidant properties of the prepared extracts.
Results. All extracts showed antioxidant activity, but in each of the methods used, the highest properties were found in the kiwi fruit´s peel extract prepared in 70% (v/v) ethanol. Lower values were obtained for the extracts from kiwi pulp and seeds, but their antioxidant potential differed depending on the assessment method used.
Conclusion. Actinidia chinensis fruits along with their peel may constitute a valuable source of nutrients with antiradical potential, helping to eliminate the negative effects of oxidative stress.

Key words:  kiwi fruit, DPPH, FRAP, Folin-Ciocalteu method, antioxidants