Epsilon Open Archive

Abstract

Horticultural plant materials not usually used from onion, carrot, beetroot, sea buckthorn, black and red
currants as well as a wastewater powder from olive oil production were analyzed for total phenols content
(FC), ferric reducing ability of plasma (FRAP), radical scavenging capacity (ABTS), and for major phenolic
compounds by HPLC-MS. Antioxidant capacity and phenol content varied significantly between
species and cultivars, with extracts of sea buckthorn leaves being superior. In different species, different
phenolic compounds were closely associated with FRAP, ABTS and FC. For instance, hydrolysable tannins
were major antioxidants in sea buckthorn whereas quercetin was the major antioxidant in onion peel and
skin. This study shows that horticultural plant materials usually left in the field or waste materials from
processing may have high antioxidant properties, and that extracts of these materials therefore could be
of potential interest for development of antioxidant food additives.