Nutraceutical potential of selected spices, vegetables used as animal feed, and agri-food wastes

Due to their health effects, the consumption of vegetables, fruits, and spices has been encouraged for a long time. The compounds responsible for the health benefits of these foods are products of the secondary metabolism in plants known for their ability to prevent or remove free radicals and repair oxidative damage. These active biomolecules are distributed in both edible and inedible parts of foods and in spices. The aim of this research was to evaluate phenolic concentrations and antioxidant activity of 3 spices native of the Far East (wasabi, ginger, and turmeric), one spice native of the East Europe (horseradish), two vegetables used in animal feeds (carobs and horse beans), and three agro-industrial wastes (pistachio hulls, pomegranate peels, and tomato stems). The phenolic fractions were extracted using water as solvent. The highest phenolic concentrations and antioxidant activity were detected in pomegranate peels. Traditional spices, horse beans and tomato stems had the lowest antioxidant contents.