Assessing Physicochemical Parameters, Bioactive Profile and Antioxidant Status of Different Fruit Parts of Greek Eggplant Germplasm

Abstract

Eggplant is an economically important vegetable with a potential for functional food production, mainly due to its high fruit antioxidant capacity. The goal of the present study was to investigate the main physicochemical and antioxidant parameters, and assess the bioactive profiles, of 19 eggplant genotypes of diverse origin, including Greek commercial varieties and hybrids, landraces and the related species S. macrocarpon. For that reason, the physicochemical traits (dry matter, pH, total soluble solids and total acidity) were assessed in the eggplant fruit and some important bioactive compounds (total phenols (TPC), total flavonoids (TFC), total monomeric anthocyanin (TAC), chlorogenic acid (CA) and its isomers neo- and crypto-CA) were assessed both in fruit pulp and peel. In addition, the antioxidant capacity was assessed according to ABTS•+, DPPH• and FRAP assays. The results revealed significant differences between the studied genotypes for all the evaluated traits, for both fruit parts. Solanum macrocarpon showed a distinct bioactive profile and was superior for most of the pulp traits (TFC, neo-CA, crypto-CA, ABTS•+, DPPH• and FRAP). Among the eggplant materials, the landrace ‘KD054/07’ had very high values for pH and some pulp traits (TPC, CA, ABTS•+ and FRAP), while the commercial F1 hybrid ‘Nilo’ was superior for dry matter and most of the peel traits (TPC, TFC, ABTS•+ and FRAP). The Greek commercial variety ‘Langada’ performed well for TAC and peel CA, ABTS•+ and FRAP, while ‘Tsakoniki’ had very high anthocyanin and pulp TPC content. These results constitute a source of information for a subset of the Greek eggplant germplasm and could contribute both to the promotion of Greek varieties of high bioactive and antioxidant value, as well as to the targeted selection of parents in breeding programs.