Antioxidant Capacity and Bioactive Compounds Accumulation in Peach Breeding Germplasm

Abstract

Antioxidant capacity and accumulation of bioactive compounds (total phenolics, flavonoids, and anthocyanins) were evaluated in 132 peach/nectarine cultivars, representing modern peach [ Prunus persica(L.) Batsch] breeding germplasm available and/or produced in the U.S. market. Accumulation of bioactive compounds and antioxidant capacity was highly variable and influenced by flesh color, ripening season, release date, genotype, and environment. Peach germplasm accumulated on average 50.9 mg GAE/100 g FW of total phenolics (ranging from 22.9 – 110.7), 15.2 CE/ 100 g of FW flavonoids (ranging from 2.1 to 56), and 6 mg C3GE/ kg FW anthocyanins (ranging from 1.6 – 19) with an observed average antioxidant capacity of 652.6 μg TE/ g FW (ranging from 93.3 – 2,115.3). Ripening season influenced accumulation of bioactive compounds, with antioxidant capacity and phytochemical content increasing as the season progressed. The highest antioxidant capacity (> 1000) and accumulation of bioactive compounds were measured in heirloom cultivars, such as yellow-fleshed ‘Elberta’ and ‘Jerseyqueen’, and white-fleshed ‘Belle of Georgia’. Different climatic conditions during the years of study resulted in higher antioxidant capacity in 2013 than in 2012 and 2014. However, anthocyanin accumulation was significantly higher in 2012 than in the other two years, while accumulation of both total phenolics and flavonoids were higher in 2014. Antioxidant capacity and accumulation of flavonoids and total phenolics (r = 0.838 and r = 0.501, P < 0.01, respectively) were positively correlated. These results clearly show the high nutritional value of peaches available on the U.S. market and suggest that the peach breeding germplasm offers a valuable resource for increasing nutritional value in breeding programs. Additional knowledge of nutritional quality existing in modern peach germplasm will facilitate development of new peach cultivars with increased phytochemical composition, therefore providing tastier and healthier food choices for consumers.